Disco 4 Dual battery issues - Battery drain

[Tommy Armstrong]

Hi everyone. Real long post, apologies in advance.

I have a disco 4 that's losing battery storage in both the main battery and auxiliary battery at fast rates.

I run ctek Bluetooth monitors on both batteries. They alerted me saying that over 2 days on freshly charged full batteries, the auxiliary drops to 70% and lower and the main to 75%.

I even charged the batteries up to full one day, disconnected the charger, drove a total of 2 hours and on the way home ran the headlights and spotties and the ctek said I had 97% main battery and 80% auxiliary.

People have said not to trust the ctek devices so I used the multimeter yesterday.

I put the multimeter on the batteries (I've only got a basic knowledge on how to use it) and the main read 12.83v and the auxiliary 12.85v.

1 and a half days later the auxiliary shows 12.45v and 12.18v for the main battery. I've disconnected the negative off the auxiliary and just waiting for 2 hours to see if it changes the figures on either battery.

I have the following things installed in the vehicle that I think could drain the battery when off:

LLAMS - led light is off.
UHF - head unit is off.
Dual air compressor install - switch is off with no leds showing
TPMS - Unplugged when vehicle is off.
Traxide system yellow top battery.

I thought maybe the alternator isn't charging properly but under idle the main battery gets 14.89v with lights and aircon running.

What I have noticed is that I have a draw on the auxiliary battery during running with the headlights and spotties on and the spotties are connected to the main battery. I lose approx .02v every minute during idle while the main battery seems to charge. Now I know with the traxide system that main charges before the auxiliary but I'm stumped with the losses on the auxiliary when the spotties are on.

I've attached a screen shot of fuses I checked yesterday to check for high current draw. Hoping I'm doing this right. I couldn't reach the lower dozen odd fuses in the bottom of the glove box because of my bad back. Also tested the ones in the engine bay. They were tested with the vehicle off, unlocked and the passenger door and bonnet opened.

Could anyone please tell me if any of these fuses look like they are drawing too much.

Also apart from the cteks drawing 2ah per month (manufacturer spec) and everything else looks like it's turned off could the LLAMS, air compressor or UHF be drawing anything?

And does the car need to be locked overnight for it to turn off all cpus. I've read the car does it after a few minutes anyway but I'm wondering if it's a cause of the drain.

Tim from traxide is also trying to run me through some tests for the traxide system but also advised me to post on here for assistance.

Thankyou to all.

[Tombie]

Yes the car needs to be locked to fully shut down.


What do you have attached to the aux battery?
Any USB sockets on either battery?

[Bulletman]

Gday Tommy,

With some of the stories i have heard about the latest crop of optima batteries I would be gettin it load tested myself. The start battery dropping will likely be the cars systems , but the optima dropping so much points towards a suspect battery in my very limited knowledge..

Bulletman

[Tommy Armstrong]

Hi Tombie.

I have the 2 x 12v sockets in the boot connected to the auxiliary via the traxide and neither have anything plugged in.

[Tommy Armstrong]

Tombie regarding not shutting the car down I'm assuming the cpus will slowly drain the main battery then. During this latest test I did lock the car every time but the batteries are still draining.

[Tommy Armstrong]

Bullet man, chatted to Tim today and he has so far narrowed down that the main battery was weighing down the auxiliary (drain is on the main battery). I'm currently charging both batteries to full then disconnecting the main battery then leaving it overnight to see what happens to both of them.

In the meantime it looks like I need to narrow down what's draining the main battery.

Hopefully someone on the forum can help me narrow down the issue from the draw on the fuses I posted.

I'll also be taking the auxiliary battery to get tested once this is all done to make sure it's also good.

[ian4002000]

The Ctek bluetooth battery monitors will use quite a bit of power. Can you put a switch on them and turn them off ?

Ian
Bittern

[discorevy]

Failing diode pack on alternator is another common issue, that will drain the main battery

[Tommy Armstrong]

Hi Ian.

A switch to turn them off would be handy. I only use them when I go camping to monitor the battery storage with the fridge running.

[Tommy Armstrong]

Discovery wizard how do I test for a failed diode pack please?

[drivesafe]

The Ctek bluetooth battery monitors will use quite a bit of power.
That quite interesting, and idea of their power consumption?

I only use the BM2 Bluetooth Battery Monitors and they claim a power usage of just 1ma.

I have not bothered to test this out.

[Aussie Jeepster]

That quite interesting, and idea of their power consumption?

I only use the BM2 Bluetooth Battery Monitors and they claim a power usage of just 1ma.

I have not bothered to test this out.

Just found this but doesn't help much.

161772

[l00kin4]

That quite interesting, and idea of their power consumption?

I only use the BM2 Bluetooth Battery Monitors and they claim a power usage of just 1ma.

I have not bothered to test this out.

According to Ctek specs less than 1mA @12.5V

https://www.ctek.com/storage/BBB54B70574D58B80D39875F5DEBBBC643DDEB1F3D368F9BF7 AD4ECBB4C585B2/67867cd471384f9bbc643d9267031c81/pdf/media/1b534c0229314ceaa9d3be1e53098014/CTX_BATTERY_SENSE-safetyinstruction-low-UK-EN.pdf

[Tombie]

Just found this but doesn't help much.

161772

Solves the issue... line 4 of the spec - hardly a dent.

[Tommy Armstrong]

I found something on the net that said 1ah over a month.

[Old Farang]

I've attached a screen shot of fuses I checked yesterday to check for high current draw. Hoping I'm doing this right. I couldn't reach the lower dozen odd fuses in the bottom of the glove box because of my bad back. Also tested the ones in the engine bay. They were tested with the vehicle off, unlocked and the passenger door and bonnet opened.
Not sure just how you are testing the fuses, but the following may help:

https://static1.squarespace.com/static/582b77aa6a4963c3f199b0a5/t/5989d6f3d482e9b676e942b5/1502205684108/Fuse_Voltage_Drop_Chart_-_Standard_Fuse.pdf

https://us.autologic.com/news/testing-parasitic-draw-via-fuse-voltage-drop

You cannot be showing 10 amps across a blown fuse.

[Tommy Armstrong]

Hi Old Farang.

I wasn't showing 10amp across the old fuse.

The fuse is a 10amp and was blown.

The other tests show the amperage showing through the meter.

Thanks.

[Tommy Armstrong]

Is anyone on the forum able to advise if the draw through the fuses is normal please? Any advice regarding finding what's causing the batteries to go flat would be appreciated.

Thanks.

[Old Farang]

Hi Old Farang.

I wasn't showing 10amp across the old fuse.

The fuse is a 10amp and was blown.

The other tests show the amperage showing through the meter.

Thanks.
On the screen shot that you posted you have shown all the readings in mV (millivolts). To be able to read ANY current draw (amps) your test instrument HAS to be in series with whatever circuit that you are trying to read. If you read the mV "drop" ACROSS the fuse while it is still in the circuit, then you need to cross reference whatever reading that you have with the charts that I posted.

It is possible to use a "clip on" ammeter around the wire you are trying to monitor, but it needs to be a good quality meter to accurately read milliamps.

[GIL]

Not sure just how you are testing the fuses, but the following may help:

https://static1.squarespace.com/static/582b77aa6a4963c3f199b0a5/t/5989d6f3d482e9b676e942b5/1502205684108/Fuse_Voltage_Drop_Chart_-_Standard_Fuse.pdf

https://us.autologic.com/news/testing-parasitic-draw-via-fuse-voltage-drop

You cannot be showing 10 amps across a blown fuse.



Hi Old Farang,
Thanks for the info.
It will help me in my investigation.
Regards
GIL

[Tommy Armstrong]

Update - Tim from Traxide helped me see if the health of both batteries are good and turns out they are. So I'm now in search of power drawing from somewhere. Problem is I've got no knowledge in how to find it with almost zero knowledge on how to use the multimeter. Is there anyone in the NSW Central West area with experience that could show me? I'm also heading to Melbourne in a week. I'd like to learn. Thanks.

[Tote]

You don't have a brake controller do you? Mine used to draw enough current to flatten the battery over a couple of weeks.

Regards,
Tote

[Ozzy119]

I have exactly the same issue and set-up. But batteries are always dropping without obvious devices causing power consumption.

But to answer the previous post, I also have a Tekonsia brake controller. So I need to unplug and see if that is the silent consumer.

[Tote]

I have exactly the same issue and set-up. But batteries are always dropping without obvious devices causing power consumption.

But to answer the previous post, I also have a Tekonsia brake controller. So I need to unplug and see if that is the silent consumer.

Mine was a Tekonsha as well. It doesn't seem to flatten the battery as quickly in the Defender but I wonder if it is a cumulative effect with the Tekonsha adding to the problem. We were overseas for a month and the Defender was pretty slow to start, also the drain on the battery starting the Defender would be less without climate control and other systems waking up when the key is turned on.

Regards,
Tote

[INter674]

Now having the Redarc I realise that my previous Tekonsha units x3 were.. well..rubbish and yes they drain power unless wired via a relay 😞

[DiscoMick]

Does the screen stay lit on your Tekonsha when stopped?

[Dagilmo]

Now having the Redarc I realise that my previous Tekonsha units x3 were.. well..rubbish and yes they drain power unless wired via a relay 😞

I agree. Having moved from a Tekonsha in the 3 to the (already installed) Redarc in the 4, I'm amazed at how much better the Redarc is.

[INter674]

I agree. Having moved from a Tekonsha in the 3 to the (already installed) Redarc in the 4, I'm amazed at how much better the Redarc is.

Yup..same here was fitted to the car.. I can set and forget whereas the Tekonsha was alway doing weird stuff like locking all the wheels at low speed braking ...so back off..and then not working at all.

Tried all sorts of settings and mountings but it did the same stuff. I have one in the tractor and it is just the same as the ones in previous cars..weird🙄

[DiscoJeffster]

Bin it. Redarc tow pro elite so much better!! No drain issues and works a treat, plus the remote head means a neat install.