Discovery 4 "smart" charging system.

[GIL]

Hi Folks,
A long post. My apologies first up.

A questioning of the "smart" charging of the Disco 4.

I have been concerned with the charging/battery monitoring regime of my D4 (2013 TDV6 8-spd).
I seem to have no trouble with the "smart" charging aspect as I tow a caravan and run with headlights ON which seems to give me fully charged batteries. I have a Piranha dual battery management system fitted which separates the two batteries at 12.8v.

The issue I see is that when stopped and parked, the battery monitoring system flattens the start battery to around 12.4v in 1-2 days, where it then stays for another 2-4 days before slowly discharging to 12.0v or slightly below after typically 2 to 2 1/2 weeks.
At this point a 'Low battery. Start the car.' message could be displayed.

I have seen a Jaguar writeup indicating the battery monitoring system flattens the start battery to around 80% state of charge (12.4v) to get an understanding of the condition of the battery, so it can then tailor the "smart" charging of the battery and provide headroom for the charge resulting from regenerative braking, when the system ramps up the alternator output on vehicle deceleration.

Nanocoms Genesis indicates there is a CCF setting where the Battery Monitoring Sensor can be set to 'without Battery Monitoring Sensor'.
Has anyone tried this?
Does this setting then command the ECU to default to standard charging profile at (I presume) around 13.8v?


Has anyone else observed this behaviour?
Is anyone else concerned with this behavior?
Has anyone else disabled this "smart" behaviour?

Thanks for reading all this and I hope it prompts a discussion.
There are MANY generous gurus on AULRO.

Regards
GIL

[ian4002000]

The voltages you are getting over the time period seem normal and what i would expect from D4. I suggest either drive the vehicle more or add a solar panel to keep the battry charged.
I am looking for a flexible stick on solar panel for my D3 to keep its battery fully charged. i have heard that a solar panel can be put inside a window and still produce useful current but i have not tried this yet.

Ian
Bittern

[GIL]

Hi Ian,
Thanks for the response.
I agree the symptoms are normal.
I'm wondering if we can change the behaviour of the Battery Monitoring Sensor so that it does not discharge a fully charged battery to 80% SOC.
I have a hookup from the van to use its solar to maintain the start battery, and via the AUX battery management system the Aux battery.
This was suggested by Tim from Traxide in 2018 in a post.
When I disconnect the van the Battery Monitoring Sensor does its thing and drops the start battery to 80%SOC over 1-2 days. This is what I find irritating.
If I leave the van connected the car tries to discharge its batteries as well.
Charging at home is fine but when I am away it irritates me I have to take these charging precautions. Hence my posted questions.
I have seen in a VW that its start/stop can be disabled (and its smart charge) by simply disconnecting the sensor connector. This results in a Battery Monitoring Sensor failure error and dash battery light in the D4. Even disconnecting the 12v sense wire from it, leaving the LIN bus wire gives the same result.
So, what other options are available?
Thanks all.

GIL

[Milton477]

I also have a fridge in the D4 which runs off a Traxide SC80 system with two 55aH batteries.
In the past, I have noticed that the D4 was not charging sometimes after being stationary for a couple of days with the fridge running. A couple of stop/starts later all returned to normal.
To get around the battery management system I leave the D4 connected to the van or I connect to a 200W solar panel which lives on the roof bars.
I keep an eye on the Generator/alternator set point value in my GAP tool to see what the system is requiring of the alternator.

As a side note, Running a DC2DC to charge LifePO4 batteries in my van can create some interestingly high numbers around the alternator current & set point if the D4's dual battery system is low on charge. I have resorted to disconnecting the DC2DC until the D4 batteries are reasonably charged & the alternator current drops to 70 amps.

[GIL]

Hi Milton477,

Thanks for your input.
I also run a fridge in the back of the D4 and I have a little cigarette lighter socket voltage display unit connected as well. Also a 2nd one on the car accessories circuit so I can monitor both start and aux batteries.
I have not noticed a delay in charging other than the 2-4 seconds after a engine start before the voltage starts climbing to 14.7v.
With the van connected to the start battery both batteries stay charged but the "smart" system in the D4 can try to discharge ALL batteries in an attempt to ascertain battery SOC and this aspect is what I am curious to investigate.
If it is possible to disable the Battery Monitoring Sensor in the D4 MAYBE it will not discharge my fully charged batteries so quickly.
I am also not really surprised by the large current you are seeing as the alternator is , I think, 180A.

GIL

[drivesafe]

Running a DC2DC to charge LifePO4 batteries in my van can create some interestingly high numbers around the alternator current & set point if the D4's dual battery system is low on charge. I have resorted to disconnecting the DC2DC until the D4 batteries are reasonably charged & the alternator current drops to 70 amps.
Hi Milton, what size DC/DC unit do you have?

[drivesafe]

Hi Folks,
A long post. My apologies first up.

A questioning of the "smart" charging of the Disco 4.

I have been concerned with the charging/battery monitoring regime of my D4 (2013 TDV6 8-spd).
I seem to have no trouble with the "smart" charging aspect as I tow a caravan and run with headlights ON which seems to give me fully charged batteries. I have a Piranha dual battery management system fitted which separates the two batteries at 12.8v.

The issue I see is that when stopped and parked, the battery monitoring system flattens the start battery to around 12.4v in 1-2 days, where it then stays for another 2-4 days before slowly discharging to 12.0v or slightly below after typically 2 to 2 1/2 weeks.
At this point a 'Low battery. Start the car.' message could be displayed.

I have seen a Jaguar writeup indicating the battery monitoring system flattens the start battery to around 80% state of charge (12.4v) to get an understanding of the condition of the battery, so it can then tailor the "smart" charging of the battery and provide headroom for the charge resulting from regenerative braking, when the system ramps up the alternator output on vehicle deceleration.

Nanocoms Genesis indicates there is a CCF setting where the Battery Monitoring Sensor can be set to 'without Battery Monitoring Sensor'.
Has anyone tried this?
Does this setting then command the ECU to default to standard charging profile at (I presume) around 13.8v?

Hi Gil, while I have no idea how the Jag system works, with the disco4s, the BMS periodically discharges the battery down to 12.2v ( theoretical 70% SoC governed by the load being applied ) and once the battery discharges down to 12.2v while under load, the alternator reverts to 14.7v and the BMS then monitors how much charge the cranking battery takes and how long it takes to get back to a fully charged state.

NOTE, this can take either one long drive or a number of short drives to achieve the necessary data required.

But there have been quite a few problems with this system, like where voltage have remained at 12.2v and other issues, that there is a software patch for the corrections.

Next time you are at a dealers for servicing, ask them to check that the upgrade has been carried out.

[GIL]

Hi Drivesafe,

Thank you for the response.
How long would you expect for the battery to take to get down to the 12.2v level under the Battery Management System control?
I presume around 2 weeks as this seems where mine sits. There are quite a few posts over the years which say to just charge the start battery every 2-4 weeks to keep it healthy.
My irritation is that a modern vehicle requires this closer attention. I had a D2 prior to the D4 and I suppose I am comparing the difference in behaviour. The D2 stayed charged for a lot longer.

Thank you for the tip about the software update. I will enquire.

Do you have any knowledge of the CCF setting for the Battery Management Sensor?
If it does revert to a standard charge profile like 13.7v and the battery is NOT discharged I will tolerate the resultant extra fuel used, negligible though I suspect it will be.

At the moment I connect the start battery to my van and let its solar keep everything charged, as you suggested in a post in 2018. This is working, but I have noticed that the Battery Management System will try to discharge the van batteries on occasion.

GIL

[Milton477]

Hi Milton, what size DC/DC unit do you have?

50A (Well that is what it is set to)

[drivesafe]

At the moment I connect the start battery to my van and let its solar keep everything charged, as you suggested in a post in 2018. This is working, but I have noticed that the Battery Management System will try to discharge the van batteries on occasion.
GIL
If this is the case, then there is something wrong somewhere in your system.

Your BMS should not be active once the ignition is turned off.

Even when the system is carrying out the battery test, it is only done while the MOTOR IS RUNNING.

[drivesafe]

50A (Well that is what it is set to)
Hi Milton, it may pay you to check out your system, because while driving at open road speeds, you should be able to get around 100 amps for charging batteries.

I have monitored my RR and it would charge low batteries with 100+ amps at 14.8v for around the first 30 minutes of a drive and the voltage would taper off from that point.

My RR has a 140 amp alternator, so it was working at full output.

[Ferret]

...Nanocoms Genesis indicates there is a CCF setting where the Battery Monitoring Sensor can be set to 'without Battery Monitoring Sensor'.
Has anyone tried this?

That's interesting. When entering the GAP tool's CCF settings for my D4 and doing a search within the BCM ecu for battery related settings the only selectable setting is 'Battery Type'.

However, if you enter 'Demo Mode' and enter the GAP tool's 'complete & untested' CCF settings for a demo D4 you can find the following battery related settings. The 'Battery Monitor Sensor' is displayed at the bottom of the list.

Perhaps to save you from yourself, all these additional settings are hidden when you are potentially editing CCF data on your own vehicle.

161777

[Milton477]

Hi Milton, it may pay you to check out your system, because while driving at open road speeds, you should be able to get around 100 amps for charging batteries.

I have monitored my RR and it would charge low batteries with 100+ amps at 14.8v for around the first 30 minutes of a drive and the voltage would taper off from that point.

My RR has a 140 amp alternator, so it was working at full output.

Thanks Tim. When the 3 batteries in the D4 are depleted, this happens:

161779

If the DC2DC is enabled at the same time as the 3 vehicle batteries are being charged as above, the voltage set point rises to 20V & the current swings wildly between 30A & 200A. I saw it happen once & intervened almost immediately & now have a remotely activated relay to control things from the drivers seat.

[letherm]

From previous posts since I joined the forum you can contact GAPIID and they will open up your device to allow access to everything - caveat emptor though. You are correct about saving you from yourself as it's on you if you brick your system.

Martin


That's interesting. When entering the GAP tool's CCF settings for my D4 and doing a search within the BCM ecu for battery related settings the only selectable setting is 'Battery Type'.

However, if you enter 'Demo Mode' and enter the GAP tool's 'complete & untested' CCF settings for a demo D4 you can find the following battery related settings. The 'Battery Monitor Sensor' is displayed at the bottom of the list.

Perhaps to save you from yourself, all these additional settings are hidden when you are potentially editing CCF data on your own vehicle.

161777

[Ferret]

From previous posts since I joined the forum you can contact GAPIID and they will open up your device to allow access to everything

Supposedly I have the 'opened' version they only make available to those that ask.

[drivesafe]

Thanks Tim. When the 3 batteries in the D4 are depleted, this happens:

161779

If the DC2DC is enabled at the same time as the 3 vehicle batteries are being charged as above, the voltage set point rises to 20V & the current swings wildly between 30A & 200A. I saw it happen once & intervened almost immediately & now have a remotely activated relay to control things from the drivers seat.
Hi again Milton, and was the 20v reading was at the alternator?

My GUESS is that the voltage at the cranking battery was still at 14.7v, which is the maximum safe voltage for an AGM cranking battery.

Did you by any chance monitor the INPUT voltage at the DC/DC device?

[GIL]

If this is the case, then there is something wrong somewhere in your system.

Your BMS should not be active once the ignition is turned off.

Even when the system is carrying out the battery test, it is only done while the MOTOR IS RUNNING.

Hi Tim,

Thank you for your response.
Your knowledge and insight just gave me a "light bulb" moment.

I have had the car for 2+ years and always regarded the behaviour as normal. A mates car behaves similarly (he tows also) and there are quite a few posts on AULRO with similar sentiments.

However, I have not critically looked at the car, and its additions for the source of problems. I am doing so now.

Found the van brake controller permanently wired to start battery via a thermal circuit breaker. Disconnected so I could monitor current draw. It takes 30-40mA when powered up and sustains this for 2-3 minutes. It then settles down to 18-20 mA til its logic seems to time out, which takes 14-15 minutes. It then drops to about 10 mA from then on.
All this is not huge, yes. Comparing this to the workshop manual published quiescent current draw it is an increase of 50% long term. The wrinkle is that when the door is opened the unit wakes up again and draws 18-20mA again, and of course opening the door wakes up the car interior etc. This happens quite often when we are away but not much at home where the car gets intermittent use.
I need to get the use of a tong type tester to check the cars quiescent performance.

Oh, and the start battery was new just a couple of months prior to my acquiring the car, so I don't believe it to be giving trouble yet, since the behaviour has not changed - but its not impossible.
The hunt continues.

Ferret,
Interesting GAP also shows the setting. Do you know what GAP shows as the options for this setting?
I have not changed mine yet but it is under consideration once I am satisfied there are no underlying issues with the car. But as Tim advised above the BMS only operates when the ignition is on. So, maybe I'm chasing shadows there.

Regards
GIL

[Tombie]

Also keep in mind. Just because a function is listed in the expanded CCF doesn’t mean:
- the setting works
- changing it works
- changing it doesn’t cause a reaction outside of expectations

[drivesafe]

Hi GIL, I have not looked at any reprogramming, but if you are going to try this method, can I suggest you see if you can disable/turn off the smart alternator function and you should then see a constant 14.3ish volta at all times.

This is the perfect operating voltage, but as posted, I have not looked at this and it may not be something that can be done with a Land Rover’s BMS.

[GIL]

Hi folks,

Tombie
Granted. Not everything works as anticipated all the time.
I wont be getting to the CCF stage until I am SURE no other issues are present in my car.

Tim
If/when I get to this CCF thing I will look to see what settings seem to be available for both the BMS and alternator. Thank you again for your expertise and knowledge.
Regards
GIL

[DieselLSE]

There's nothing in the CCF about the BMS. Only battery and battery type gets a mention.
Under Battery, 74% of cars were supplied with H8HD 90Ah 950 Cold Cranking Ampere and 26 with T7 80Ah 700 Cold Cranking Ampere.
Under Battery Type, 66% of cars were supplied with H8 AGM 95/850 (As Built Value) and 26% with Battery type 14, 6% with Battery type 16 and 2% with Battery (conventional charge).
I am not sure what the relationship is between the two entries, if any.

[GIL]

Hi DieselLSE,
Thanks for the input.

I found the CCF entry via Nanocoms Genesis website under 'Warnings and Messages'. The setting was 'Battery Monitoring Sensor' and 98% of the cars had it fitted.
It is an assumption that this is referring to the Battery Monitoring System fitted to my 2013 D4.
But, I have not pursued this yet due to refocusing my efforts on parasitic current drain.
If I am satisfied this is OK, I will then reexamine the Battery Monitoring Sensor setting.
Regards
GIL

[LRD414]

Found the van brake controller permanently wired to start battery via a thermal circuit breaker. Disconnected so I could monitor current draw. It takes 30-40mA when powered up and sustains this for 2-3 minutes. It then settles down to 18-20 mA til its logic seems to time out, which takes 14-15 minutes. It then drops to about 10 mA from then on.

That is very interesting and not something I had considered.
I have installed a plug into the Traxide earth wire so that it can be isolated when the D4 is not being used much.
Perhaps one in the TowPro earth wire is worth thinking about too, they are both earthed to the stud in front of the cranking battery.
I wonder if the GME UHF has any small drain when off.

Cheers,
Scott

[DieselLSE]

Hi DieselLSE,
Thanks for the input.

I found the CCF entry via Nanocoms Genesis website under 'Warnings and Messages'. The setting was 'Battery Monitoring Sensor' and 98% of the cars had it fitted.
It is an assumption that this is referring to the Battery Monitoring System fitted to my 2013 D4.
But, I have not pursued this yet due to refocusing my efforts on parasitic current drain.
If I am satisfied this is OK, I will then reexamine the Battery Monitoring Sensor setting.
Regards
GIL
So it is! Missed that. Looks like you could edit it to "Without..." but whether that actually switches it off would be interesting to find out. I suspect not as I have in the past made a couple of changes that had no effect.

[Ferret]

Ferret,
Interesting GAP also shows the setting. Do you know what GAP shows as the options for this setting

While the GAP tool shows the setting, it is not possible to show what options are available.

[DieselLSE]

While the GAP tool shows the setting, it is not possible to show what options are available.
Thanks Ferret, that would tend to indicate that the field is not editable in a way that is referenced by any other module.

[GIL]

Hi Folks,
Sorry I have been M.I.A.for the past few days dealing with the catastrophe of life.

Thanks all for your contribution to the discussion.

I have not driven or even opened the D4 for 5 days so it has been a good test of not having the brake controller connected.
If I hold my tongue correctly and squint I could convince myself that not having the brake controller connected has extended the time for the start battery to drop. I had the van (and thus its solar) connected to charge the start battery, and the AUX battery via the aux battery controller.
Voltage when disconnected was 14.4v 5 days ago.
Today when measured the start battery voltage was 12.5v. I think this is 1 (minimum) days longer.

I also have checked the Nanocom Genesis site for a setting to disable the "Smart" alternator (as suggested by Tim of Traxide above). I found no mention of one.
I did download my CCF with the Battery Monitoring Sensor disabled in preparation for trying it. It's not impossible that this setting causes the alternator to revert to a standard operation of a regulated output, but who knows.

On the subject of defeating the "smart" alternator. I found reference to a Ford alternator with the 3 pin control connector as was used in earlier Disco's. Apparently if it is disconnected the alternator reverts to a standard operation of a regulated output. It does however generate codes but works.
The D4 alternator is controlled by the LIN bus and I suspect that if it is disconnected we would get codes but am unsure of the ramifications.

My next step is to determine the exact quiescent current draw of my D4.
Then I will have an idea if I'm chasing a "real" fault.

To do this I need access to a tong (also called clamp) tester which will reliably measure down to a resolution of 1mA. I found this on fleabay:

BSIDE ACM91 1mA Auto-Ranging AC/DC Low Current Digital Clamp Meter NCV Temp | eBay (https://www.ebay.com.au/itm/BSIDE-ACM91-1mA-Auto-Ranging-AC-DC-Low-Current-Digital-Clamp-Meter-NCV-Temp/382945718043)

The issue with the current covid-19 environment is that I do not know how long it may take to get here.
So, are there any AULROians with a suitable tong tester in the south-east of Melbourne who could put up with me for around 1/2 hr to do the base quiescent current test. (Takes around 20 min after locking car to completely shutdown, then 5 min or so to test).

Sorry for such a long post and thanks for reading.
Regards
GIL

[Tombie]

There are a few problems I can see here.

You claim 14.4v when disconnected. This is NOT a resting voltage. You need to measure again.

How many days is it taking to drop to 12.5v?

Is yours keyless entry? As in just pull the handle?
If so, how close to your vehicle is the key inside the house?
Are you locking the vehicle each time you park up?
Do you have USB ports installed anywhere?

I would strongly suggest forgetting about “hacking” the system and search for the root cause. There’s something in there you either aren’t seeing or haven’t thought of.

[GIL]

Hi Tombie,

There are a few problems I can see here.

You claim 14.4v when disconnected. This is NOT a resting voltage. You need to measure again.

How many days is it taking to drop to 12.5v?

Is yours keyless entry? As in just pull the handle?
If so, how close to your vehicle is the key inside the house?
Are you locking the vehicle each time you park up?
Do you have USB ports installed anywhere?

I would strongly suggest forgetting about “hacking” the system and search for the root cause. There’s something in there you either aren’t seeing or haven’t thought of.

The 14.4v was directly after disconnecting the van, so it was full surface charge not resting voltage.

It took 5 days to go to 12.5v. I didn't measure the voltage during this time.
Car does not have keyless entry only keyless start. Its the pauper pack.

The key is at least 10 metres from the car when I'm inside. I saw somewhere (in Workshop manual?) that the key should be >5mt from the car when conducting quiescent current testing.

Yes, I double lock the car when leaving it. I understand this action more completely shuts down the car.

USB ports. I only have the standard USB ports. The only one used is the one in the cubby lid. The car is fitted with the mid range audio system which has the larger centre dash display screen and the USB port in the cubby lid is accompanied by an ipod port which I do not use. The car has also got the Technology Pack installed.

Completely agree with chasing the current drain before contemplating the CCF change.

Thanks for your advice and insights.
Regards
GIL

[drivesafe]

It took 5 days to go to 12.5v.
Hi GIL and with a battery voltage of 12.5v after 5 days, you do not have a problem.

At 12.5v, your battery is around 90% SoC.

[GIL]

Hi Tim,
Thanks for your input.


Hi GIL and with a battery voltage of 12.5v after 5 days, you do not have a problem.

At 12.5v, your battery is around 90% SoC.

So to summarise.
If by disconnecting my brake controller I have achieved a normal behaviour of the system, should I change the brake controllers power supply source to an ignition switched relay?

Regards
GIL

[DieselLSE]

Hi Tim,
Thanks for your input.



So to summarise.
If by disconnecting my brake controller I have achieved a normal behaviour of the system, should I change the brake controllers power supply source to an ignition switched relay?

Regards
GIL
If you do, and you don't have a cubby cool box, you can use Central Junction Box fuse 16P as it is ignition powered. See attached extracted page from the D4 Electrical Wiring Diagrams Manual. My preferred method of tapping into an unused powered feed (i.e. one that is powered - by the ignition in this case - but does not have a fuse in place) is to use a piggy back dual fuse holder with the original circuit's fuse removed, so that only the new circuit that you need is powered.

[DiscoJeffster]

Brake controllers need a lot of amperage to drive the electric brakes (assuming it’s an electric brake controller) which is why the instructions will state to connect it with decent cable and individually fused to the battery. Also if it’s like mine (Redarc tow pro) it calibrates itself each time it loses power and won’t work correctly until recalibrated, which can be annoying, albeit briefly.

Connect an ammeter in-line with the brake controller and measure it’s actual draw at different times, or alternatively reconnect the brake controller and redo the experiment.
—-
What is the model of brake controller and have you checked to see if it’s wired up correctly? I bet it’s got an ignition trigger wire to help put it to sleep that’s connected to battery permanently that’s causing your issue. Installer couldn’t find a trigger so wired it permanently on.

[Old Farang]

To do this I need access to a tong (also called clamp) tester which will reliably measure down to a resolution of 1mA. I found this on fleabay:
That should work ok, I have a similar unit. An old trick if you are chasing very low currents, providing there is enough slack in the wiring, is to pass the conductor through the jaws of the clamp meter TWICE. Then just halve what ever reading that you observe.

[Tombie]

Reading your results and the testing you are carrying out, I’m arriving at the result that you are chasing a non-existent issue.

The BMS will not discharge to 80% whilst the vehicle is off.
The vehicle slowly lowering voltage is a result of door opening and closing whilst parked up - normal, as it wakes up expecting to be started shortly after opening. The BMS will protect the vehicle to a certain extent, warning you when you’re getting close to low.

These vehicles will start down to around 11.8v.
When camping for extended periods use a solar panel either into the vehicle or by keeping the van linked to share its charge (depends on your system and how connected).

I think you may be chasing ghosts.

[ramblingboy42]

I'm not quite understanding something here,

Why does the battery management system "try to discharge the batteries"?

This doesn't make any sense to me at all. What software commands are doing this and for what reason?

These are the kinds of things in modern systems that concern me and turn me away from purchasing latest products.

I don't want to have to be concerned about this type of stuff when I'm doing my bush pilgrimages each year where I just cannot afford a purposely flattened battery.

This is why I'm thinking of "downgrading" to something like a perentie. Sensibility says do it.

[Dagilmo]

This is why I'm thinking of "downgrading" to something like a perentie. Sensibility says do it.

I wouldn't discount a horse and cart....[smilebigeye]

[drivesafe]

I'm not quite understanding something here,

Why does the battery management system "try to discharge the batteries"?

This doesn't make any sense to me at all. What software commands are doing this and for what reason?

These are the kinds of things in modern systems that concern me and turn me away from purchasing latest products.

I don't want to have to be concerned about this type of stuff when I'm doing my bush pilgrimages each year where I just cannot afford a purposely flattened battery.

This is why I'm thinking of "downgrading" to something like a perentie. Sensibility says do it.
Basically, it is a means of testing as to whether the battery is in a good condition, or needs replacing.

But, I am yet to see a post or report, where this test deemed the battery needed replacing, and indicated in some way that this was needed.

[GIL]

Hi Folks,
Thanks all for your insights and input. Hopefully we are all learning about our amazing vehicle.

DieselLSE
Thank you for the info about fuse 16P in CJB. This could work well as the thermal circuit breaker for the brake controller is mounted internally on the front wall of the start battery box.

DiscoJeffster
My brake controller is a Tekonsha Prodigy. I moved it from my old D2 onto the previously installed wiring for the controller (Redarc with the RED knob) the car had when I acquired it, which by the way was mounted INSIDE the cubby box. I checked the wiring install and it seemed to follow the recommended pattern. +12v direct from battery via thermal circuit breaker, ground, brake sense (from rear LHS light IIRC) and output to van brakes. This was also the installation I had in the D2 and which I ran for 10 odd years.

Old Farang
The cable I thought would be the easiest to measure the quiescent current drain on is the big battery to CJB one. As such there is neither the room or the flexibility to allow multiple wraps in the tester tong.
However this multiple wrap trick is good.

Tombie
The reason I started this investigation is that I was concerned at the (compared to my old D2) short time it took for the start battery to drop to the stage the car prompted for a start. I have 2 mates with D4's and both see similar behaviour so initially I thought this was normal. Both also tow vans. Anyway I started checking and also this post to canvas the knowledge and wisdom of the brains trust of AULRO.
I think the discussion in this thread proves the point of how good and sharing are the members.

Now that my brake controller seems to be a contributor my cars behaviour, I will see if I can mitigate its influence. eg relay fed power.
As to the other thoughts eg CCF yes I think it is chasing ghosts. The car does what I want it to do and I do not want to change for changes sake.
Your insights are always welcome and worthwhile. Thanks.


To all, thank you for the discussion.

I have a solo 100km round trip, maybe tomorrow, so I will get a chance to leave the brake controller disconnected and start the monitoring time again. I will report results.

Best Regards
GIL

[Tombie]

Something to consider.
If you relay the brake controller, and there is an engine failure / system shut down, whilst towing there is potential for the controller to power down.

At that point (very unlikely) you may not have the assistance of the trailer brakes.

Prodigy controllers are known for pulling a bit of power as you are seeing, perhaps consider an upgrade to the Redarc unit. Myself and several others haven’t experienced any problems.

[Tombie]

The Tekonsha P3 has history of causing issues.

An initial thread after concerns were raised
Tekonsha P3 Battery Drain (https://www.aulro.com/afvb/l319-discovery-3-and-4-a/227493-tekonsha-p3-battery-drain-3.html)

The Controller will wake every time it feels movement - so a door closing and opening will wake it up.
Some have also been known to wake up randomly by themselves.
There have even been instances where brake lights have been observed randomly coming on and off with the vehicle at rest.

There have been a few people with issues over the years.
Tekonsha Brake control (https://www.aulro.com/afvb/l319-discovery-3-and-4-a/90572-tekonsha-brake-control.html)

[GIL]

Hi Folks,

Tombie
My brake controller is a Tekonsha Prodigy P2. Its been with me since 2001 being installed in my D1 then D2. Its not impossible it has degraded but I haven't noticed any deficiency in its performance so far. I have tried a friends later model with no change in the D4's behaviour. At this stage I am not suspecting it.

Good point regarding the relay supplied power. As I have an AUX battery immediately in front of the start battery it might be a better solution to power the brake controller from it.
Also a good point regarding the Redarc Tow Pro. I have friends running that unit with only good reports. It remains an option.

Thanks for the links too. Seems I am only one in a series of owners chasing this type of problem.

I have found previously that when parked up while away and having the van connected to the car that the van brakes faintly 'click' every couple of minutes. Pinned that down to the brake controller testing to see if van was connected. I now disconnect van if parking up for more than 1 day.
I have the option of connecting the van to the car via Anderson plugs either to the cars rear (feeding the AUX battery) or the cars front (feeding the start battery, and when its charged it feeds the AUX battery via the Aux battery controller). This utilizes the vans solar power to charge.

All

I did go on that 100km round trip. System voltage just prior to shutdown was 14.4v as measured on cig lighter style plugin display unit.
I then double locked the car.
The next 2 days measurement of the start battery, as measured with multimeter on the Anderson plug I have from the start battery in the bull bar, were:

Day 1 - 12.8v
Day 2 - 12.7v

I will continue to take readings each day and post up the results. This may be of use to others.

Thanks again everyone for your contributions.

Regards
GIL

[INter674]

Chuck the Tekonsha Prodigy away...that was my last one..it was impossible to get it to work consistently no matter what setting or location it was set to..😞

[ytt105]

My Disco 3 had a Prodigy. I didn't like the location, but the operation was good. My new Disco 4 came with a Redarc series 2, non proportional. It was crap. I've now bought a Haymen Reese IQ. Proportional and has a great boost feature. Also, it's half the price of a Redarc series 3.
I try and stay away from Redarc as I believe although their stuff works fine, its way overpriced!

[Tombie]

The challenge of manufacturing solely in Australia vs importing Chinese production.

[drivesafe]

The challenge of manufacturing solely in Australia vs importing Chinese production.
Sorry but I do not agree.

I lost a huge amount of potential sales because a certain company’s reps were telling caravan manufacturers that WIRELESS breakaway battery monitors were illegal.

They sold a hard wired breakaway battery monitor at the time.

Wireless versions were NOT illegal but the wholesaler I was supplying, had to go to the relevant state minister in NSW and get a document which was used to inform potential buyers that the device was legal.

Then that same company bought out a business that made a wireless VOLTAGE monitor, that did NOT comply with the regulations, but they still sold it without explaining that it did not meet the legal requirements.

This is definitely one situation where I would rather sell Chinese made.

[GIL]

Hi Folks,

I have had no problem with the Tekonsha Prodigy P2 in any of the 3 cars it has now been installed in, and towing 2 different caravans.
The D4 however is the only one where I have noticed this battery behaviour.
So I guess the towed vehicle will dictate the performance of any brake controller and influence the owners view of it.

I have measured the D4's start battery voltage for the last 2 days :

Day 3: 12.65v
Day 4: 12.60v

I am trying to take the reading around the same time of day (morning) so that each reading is approx. 24 hours apart. Hopefully this regime gives a way for others to compare results.

Regards
GIL

[DiscoJeffster]

Sayings come to mind.

You can lead a horse to water, but you can’t make it drink

The definition of insanity is doing the same thing over and over again and expecting different results

Shrug.

[Tombie]

Sorry but I do not agree.

I lost a huge amount of potential sales because a certain company’s reps were telling caravan manufacturers that WIRELESS breakaway battery monitors were illegal.

They sold a hard wired breakaway battery monitor at the time.

Wireless versions were NOT illegal but the wholesaler I was supplying, had to go to the relevant state minister in NSW and get a document which was used to inform potential buyers that the device was legal.

Then that same company bought out a business that made a wireless VOLTAGE monitor, that did NOT comply with the regulations, but they still sold it without explaining that it did not meet the legal requirements.

This is definitely one situation where I would rather sell Chinese made.

That aside, as an example Drivesafe.
You spend a lot of time constructing and developing your product and assembling using AU sourced components etc.

This sets a price point you cannot avoid.

If you (example only) were to head O/S for production, and had your units made OS, the looms made OS, packaged etc they could theoretically be significantly cheaper. And would leave you solely doing R&D and distribution.

Theoretically this means either larger margins if sold for same pricing, or ability to price lower.

All of this comes at other “costs” obviously.

And that in its simplest form is why AU manufacturing faces massive challenges.

This is a simplistic example only - only highlighting the business cases and challenges to OS vs Local

[drivesafe]

That aside, as an example Drivesafe.
You spend a lot of time constructing and developing your product and assembling using AU sourced components etc.

This sets a price point you cannot avoid.

If you (example only) were to head O/S for production, and had your units made OS, the looms made OS, packaged etc they could theoretically be significantly cheaper. And would leave you solely doing R&D and distribution.

Theoretically this means either larger margins if sold for same pricing, or ability to price lower.

All of this comes at other “costs” obviously.

And that in its simplest form is why AU manufacturing faces massive challenges.

This is a simplistic example only - only highlighting the business cases and challenges to OS vs Local
Hi folks, rather than disrupt this thread, I have started a new thread about Australian Made and some the real problems this can bring.

https://www.aulro.com/afvb/general-chat/279411-australian-made-vs-off-shore.html#post3008672

[GIL]

Hi Folks,

Here are the last 2 days readings:
Day 5 : 12.57v
Day 6 : 12.56v

However I had to use the car today so that stops this sequence.
I would like 2 weeks readings to be a complete sequence.

I will see how I go and post the results.

Just to be clear, the brake controller is disconnected and as far as I am aware there is no other drain than the cars normal quiescent. However to be absolutely sure that quiescent should be measured but has not as yet been done.

Regards
GIL

[drivesafe]

Hi GIL and those voltages are pretty good.

A suggestion, to get an even more accurate idea of your battery’s true state of charge.

Next time you do a long term non use voltage measurement, first take the voltage reading just before you need to use your vehicle.

Then turn your ignition on, BUT DO NOT START THE MOTOR.

Turn your headlights on and leave it that way for at least 5 minutes.

If the battery is in good condition, the voltage should drop no more than about 0.3v and SHOULD STABILISE.

IF the voltage continues to drop, time to get the battery checked.

[GIL]

Hi Tim,
Thank you for your input.
I will do this next time I need to use the car and post the results.
I have learnt much from your posts over quite some time.

Regards
GIL

[INter674]

Re a load test..eg. my new tractor batt seemed no good...engine slow to turn over...going flat etc..

So after charging...checked voltage. 13.6v.. then cranked engine with no start (disconnect fuel cut solonoid)..for a minute...till 'flat' ...voltage 13.0v.

Soooo...not the battery.

Turned out to be a short inside the starter motor..brush insulation worn thru..easy fix fortunately😚

Glad I did not cart it into town and complain to the seller🙄

[GIL]

Hi Folks,

Inter674
You just reinforced the idea to not get fixated on one possible cause for a symptom.
Good it was a cheap and simple fix.

update.
I had to use the car today. It has been only 3 days since last use after a short trip.
So, I tested the battery SOC using Drivesafe's method above.

Results are:
Battery volts prior to test: 12.58v
Then, Ign on but no start.
Turn on headlights. Volts=11.98. NOTE: dont close the door or lights will turn off.
Wait 5 minutes. Volts=11.95
Turn off headlights and ign. volts=12.07
After 3 minutes volts=12.39
After further 3 minutes volts=12.44.

I believe the battery is 3 odd years old.

Also Drivesafe has posted this thread in 2017
https://www.aulro.com/afvb/the-verandah/246755-line-auto-electrical-info.html?246755=#post2647806

It contains lots of info.
Thanks for sharing your expertise.
Regards
GIL

[drivesafe]

Hi GIL and excellent info.

The results are not looking good for your battery, BUT.

Your battery may note be on it's way out, it may have lost a fair bit of it's capacity but it may just need some reconditioning.

The easiest way to try to recover lost capacity is to try the suggestions in this link.

On-Line auto electrical info (https://www.aulro.com/afvb/the-verandah/246755-line-auto-electrical-info-8.html)

GIL, as you have already documented your voltage readings so far, if you have the time and patience, it would be interesting to see if the reconditioning cycles work for your cranking battery.

Thanks again for the great info.

[GIL]

Hi Tim,

Thank you for the response.
I had an inkling after the voltage drop seemed outside your info above.

I will try the reconditioning process documented in your
On-Line auto electrical info (https://www.aulro.com/afvb/the-verandah/246755-line-auto-electrical-info-8.html) thread and advise results.
I have a smart 7 stage battery charger.
Regards
GIL

[drivesafe]

GIL, just a word of caution.

If your battery charger has a RECONDITIONING MODE, do not use it on any AGM battery.

The RECONDITIONING MODE of any battery charger is specifically meant for WET CELL batteries and can damage AGMs.

[GIL]

If your battery charger has a RECONDITIONING MODE, do not use it on any AGM battery.


Hi Tim,

My charger DOES have a recondition feature. It has settings for four battery types GEL,AGM,WET,Calcium. This is the only selection mode it has, although the later updated model also has a charge current setting.
The manual suggests the recondition stage provides constant current of 0.3 to 2.25 A for 4 hours and the difference between the different battery types is the voltage at which it supplies these amps - AGM being 14.4v.
So now I am a bit confused. I thought my charger was a reasonable one.
Am I doing the wrong thing by my battery by using it?
I have used it for the last couple of days overnight as suggested above in the thread.
Regards
GIL

[drivesafe]

Hi GILL and that is not a bad charger. Quite the revers.

Many chargers use a higher voltage during the RECON cycle and the voltages can go as high as 15.5v.

Not a problem for WET cell batteries but this will destroy AGMs.

If your charger makes allowances for the different battery types, use it with confidence it will NOT damage your batteries.

[GIL]

If your charger makes allowances for the different battery types, use it with confidence it will NOT damage your batteries.

Hi Tim,
Thank you for the clarification.
I will resume using the charger and see how the process goes in reference to the performance of the battery.
I will post up results after the process and another battery SOC test.

All
Thanks for everyones input to this discussion.

Regards
GIL

[GIL]

Hi Folks,
An update of battery testing and discharge readings.


I performed a battery recondition using my charger with a recondition phase in its 7 stages of operation. I followed Drivesafes procedure detailed above in this thread.
Charge for a day, disconnected overnight.

Battery took 3 days before it no longer went through the recondition stage. ie day 4 did not perform the recondition stage.
I let the charger go to the last float stage and disconnected.
The car sat overnight.

I then performed a battery State Of Charge (SOC) test as detailed above in this thread.
Opened car and bonnet then let it shut down.
Results were:

Start:12.60v headlights off to 12.05v headlights on
After 5 minutes 12.01v

End: 12.29v headlights off to 12.45v after 3 minutes then 12.55v after a further 3 minutes.

I then put the battery on charge for a day with it finishing in the float stage of the charger.

The car was double locked and sat overnight.
The car has no brake controller connected.

I tested the battery voltage each morning via an Anderson connector I have available in the bull bar as follows:

Day 1:12.81v
Day 2:12.77v
Day 3:12.71v
Day 4:12.67v

I will update for as long as the car sits idle (and that could be some time as parts of Vic are again in lockdown.)

Preliminary impressions:
Battery has held up better in SOC test and the discharge readings each morning.

Regards
GIL

[GIL]

Hi Folks,
Further update on battery readings.
The car has not been either unlocked or used.

Day 5:12.66v
Day 6:12.71v -- I don't understand this reading
Day 7:12.64v
Day 8:12.58v
Day 9:12.56v

Observation.
Day 9's reading was where the battery was at Day 6 in the first series prior to reconditioning and SOC.

Melbourne being in lockdown again will provide the opportunity to continue the readings.

Regards to All
GIL

[drivesafe]

Hi GIL, a small variation like that can be caused by temperature differences.

[GIL]

Hi Folks,

Drivesafe.
That makes perfect sense as we have had overnight temps as low as 1C and high of 9C down in Melb lately. Day time temps have been in the 'teens. Thanks.

Update on the readings of the battery.

Day 10:12.54v
Day 11:12.55v
Day 12:12.53v
Day 13:12.52v

I am pleasantly surprised at how gently the voltage is falling.

Remember the brake controller is still disconnected and the battery has undergone a recondition and SOC test as Drivesafe detailed on earlier posts in this thread. Thanks again.

Maybe his procedures are candidates for a sticky with his permission?

As we are again in lockdown in Melb I will continue taking readings, as the car is going nowhere. Can't claim good fuel economy since that while it is using no fuel, it also is not covering Km's.

Regards
GIL

[DiscoJeffster]

The recondition may have provided additional capacity, but it seems your brake controller is the culprit for shorter than normal life off charge. That said, depending on the true health of the battery, it might not have the cold crank ability to start it when it does get lower. Time will tell. Keep up the good work.

[DiscoMick]

Sounds like recondition has helped, maybe by reducing sulphation in the cells. I reckon having a solar panel permanently connected to our Defender's battery has extended its life.

[Tombie]

Sounds like recondition has helped, maybe by reducing sulphation in the cells. I reckon having a solar panel permanently connected to our Defender's battery has extended its life.

Indeed it will.

[GIL]

Hi Folks,

DiscoJeffster
Yes. The brake controller consumption has been educational. My older technology Tekonsha does consume more than the later Tow Pro Elite does and certainly is a major contributor to the time to discharge.

DiscoMick
The recondition has helped. I also have been heartened by the battery life of solar charged batteries. I have had 9 years from the ones in the van. This is one of the reasons I installed a switched Anderson plug (accessible in the bull bar) from the start battery. I can plug the car into the vans solar driven system and keep both the start and Aux batteries charged.

Update on latest readings:

Day 14:12.50v
Day 15:12.48v
Day 16:12.46v
Day 17:12.45v

Regards
GIL

[drivesafe]

Update on latest readings:

Day 14:12.50v
Day 15:12.48v
Day 16:12.46v
Day 17:12.45v

Regards
GIL
Hi GIL, as a final test to see how well your batteries are REALLY doing. Before your next drive, turn the ignition on but do not start the motor.

Then turn your headlights on and give it a few minutes.

See if the battery voltage drops a bit ( say 0.2v to 0,4v ) then levels out or if it drops well below 12.0v.

This test shows whether your batteries are not just holding their voltage, but are holding their capacity.

[GIL]

Hi Tim,

As we are in lockdown in Melb ( and possibly going to stage 4 if does not improve) the car is going nowhere.

At what voltage level would you advise I perform this test?
Do I continue down to sub 12.0v?
I believe that 11.8v is considered to be approx. 40% charged?
This is somewhere around the "Start vehicle" dash message level?

Thanks for your knowledge sharing.

Regards
GIL

[drivesafe]

Hi GIL. the "Low Battery, Start Motor" message should commence once your battery voltage is below 12.2v.

BUT, with healthy batteries, you can start your motor from as low as 11.6v.

[GIL]

Hi Tim,
Thanks again for sharing your knowledge.
I will perform the test once the readings get to 12.2v.
This may take another week at the rate voltage is dropping.

We'll see what the battery is really like then.

I'll continue to post the results.
Regards
GIL

[Tombie]

What “test”? [emoji12]

You’re ongoing posts are only confirming everything everyone else in this thread already.

[GIL]

Hi All,

Update on the readings:

Day 18:12.44v
Day 19:12.43v
Day 20:12.44v
Day 21:12.42v

Regards
GIL

[GIL]

Hi All,

Update on the readings:

Day 22:12.41v
Day 23:12.41v
Day 24:12.42v
Day 25:12.41v
Day 26:12.35v

I'm a bit surprised that the voltage has held up for the last week, but this mornings reading was a significant drop.

I'll continue taking readings til I have 4 weeks worth - 2 more days.

Then I will perform the test Drivesafe has indicated in post #70.

I'll have to do it by then anyway as I need to move the car to get my mower out and knock the heads off some daisys or we'll need a machette to get to the front door!
Regards
GIL

[GIL]

Hi All,

Update on the readings........


Day 27:12.34v
Day 28:12.34v

This completes a full four weeks of readings.

I then performed the test Drivesafe outlined in his post of 16th July 2020, 10:05 PM.

Unlocked and opened car: 11.76v
Ign ON and headlights ON: 11.50v
Wait 3 full minutes.
End: 11.41v
Ign OFF and headlights OFF
Wait 3 full minutes.
Final reading: 11.83v

I then started the car.
It did NOT display the "Low battery, Start Motor" message.
The cranking speed was slower than normal but it had NO PROBLEM starting.
Reading after a minute or so of running: 15.00v.

Ran the engine til the coolant gauge moved just above the lower Band on the gauge.
Car is now on my smart charger for overnight.

I'll see what it finishes up with and advise.
Probably should then post a summary of findings and what I have learnt.

Regards
GIL

[GIL]

Hi All,

Firstly, thank you to everyone who contributed to this thread.
A big shout out to Drivesafe for his expertise and willingness to share his knowledge.

As a summary, here is a table showing the voltage reduction over the 4 weeks of the test. Note: My battery is around 3 years old.

163332
EDIT: table didnt load 1st up. Here it is now.

What Have I learnt?
- The older style brake controllers (like my Tekonsha Prodigy) have significant current draw in their quiescent state. (10 mA)
The newer ones (like Redarc TowPro Elite) have around 1 mA.
This compares to the cars quiescent current consumption of 20 mA or less. So the shorter battery drain times I was initially concerned about can be understood.


- If you are concerned to minimise battery drain then power the brake controller from
-AUX battery
-Accessory switched power via relay.
This may require settings to be set again on power up.
-or disconnect it from power when parked.
Must remember to re-plug for the next use.
I don't really recommend this course of action.


- The Smart Battery Sensor ONLY works when the engine is running and does NOT contribute to the battery drain when parked, as I initially thought (and titled the thread accordingly).


- A battery lasts longer when charged properly. I (and others) have seen this (in the caravan installations for instance) when the charging is done by Solar Systems.



- Reconditioning a battery makes a significant change to its ability to provide its full capacity in arduous conditions.


- Drivesafe has detailed a State Of Charge (SOC) test in the thread.
This is easy to do and gives a result which could be used over the life of a battery to compare its performance as it ages.
ie. Each year or when a problem is suspected.



Where to From Here?
- I plan to connect my start battery into the vans solar system when parked up at home (essentially another battery set in the vans system). The AUX battery controller will manage the start to AUX battery connection in the car.


- Knowing the cause for the shorter time to discharge the battery I will monitor its condition more closely. Of course the solar connection will maintain its charge at home.


- I plan to perform a recondition charge every 3-6 months.


- When we are away with the van I have been connecting the AUX battery to the vans solar system anyway. I think it may be better to use the start battery connection for this. Still pondering this as there are ramifications for starting the car if problems arise with the vans batteries/system. Maybe connecting for a daytime or two each week could work.


- I will NOT be editing the cars CCF to disable the Battery Monitoring Sensor as it only works when the engine is running and will not contribute to the battery discharge when parked.

Wrapup.
I hope this extended test of the start battery discharge process has been useful. I found nothing of this detail or length when I was searching for answers prior to starting the thread.
It has reinforced the findings of a number of people who have posted in the thread and hopefully quantified them as well.
I would expect a new battery to hold voltage for a longer time and an aged battery to hold voltage for a shorter time than the tabled results here.


Thanks to all for your contributions
Warm Regards
GIL

[DiscoMick]

Useful information. Thanks for sharing it.

[GIL]

Hi Folks,
But wait.... There is a post script to this discussion.

Finally got out of town for 2 trips with the caravan.
On both we had a battery which would not start the car on cold mornings.
The 1st trip I just jump started it and all OK for the day and the rest of the trip.
The 2nd trip ( 6 weeks later) I was checking the voltage each time we went to use the car.
12.8v before unlocking and opening the car.
10.6v after. Not good.
So I have replaced the battery with a Delkor AGM LN5 (DIN88LH). CCA=900, AH=95.
So perhaps the issue I was chasing last year was the battery trying to tell me it was ailing.

Now an aside.
There are 2 types of battery which can be fitted to our D4's.
Flooded Lead Acid (WET) and Absorbed Glass Mat (AGM).
Land Rover specified AGM for the diesels after 2013/2014.
Battery specs for my 3.0 Lt diesel (2013 D4) are CCA=825/850 (depending where you look in the manual) and AH=90.
The battery I removed was a WET Century DIN85LHMF which was CCA=760. I am surprised I got so long out of it now.
Johnson Controls battery division, (which owned brand names Varta, Delkor and Optima and others Australia did not see), was sold off to Brookfield Business Partners in Jan 2021.
The specs for the Varta G14 and Delkor LN5 AGM batteries are pretty much the same. Are they just repackaged?
It seems, from my experience pricing replacements, that AGM batteries are about twice the cost of WET batteries.

I hope the above helps others who have these problems.

Thanks and Regards
GIL