Low Battery Warning and Battery BMS

[Netorius]

I think I did something stupid and looking for advice. My 2014 Discovery 4 popped up with a low battery start vehicle warning. Car had been standing for 3 weeks so I was not overly concerned. Just popped on the CTEK and left it overnight. In the morning the charger indicated fully charged, but still had the low battery warning. Check battery voltage and it was 14.2V (vehicle off) so seems fine.


I then did some research (AULRO and Google) and discovered that you must never charge the D4 battery directly on the battery terminal - always connect the negative to the body. It seeems that if you do connect directly to the negative pole (which I did), the BMS (Battery Management/ Monitoring System) sees an "overcharge" of the the battery and the only way to resolve this is by recalibrating with the GAP IID.

I read this interesting and informative article which I think is great information for the dummies like me to get some insight on the operation of the BMS on the D4.
Battery, BMS & charging – Discovery 3 / 4 – ExpeditionParts / DiscoveryParts (https://www.expedition-parts.de/en/batterieprobleme-beim-discovery/).


This gets to my actual question regarding the GAP IID - can you reset this type of fault with someone elses GAP IID or does it need to be the one that is VIN linked to your vehicle. My biggest reservations about spending the large amount on the GAP IID are:


My budget is limited, but do love my D4, and do understand the value of being able to read and reset codes.
I can see that owning the GAP IID would already save me given my battery issue described above.
I am not a "super user" and really not the sort to service and maintain my own vehicle, although I have a reasonably good understanding of mechanical / electrical issues and tinkering is fine. It is therefore hard to justify the cost for such limited use.
I do see the benefit of being able to reset codes if you get stranded, but think there are cheaper units that can do that.
I would like to invest in a diagnostic tool that I could use to help fellow motorists out of grief, or at least read and reset their codes. My understanding (limited) is the GAP seems to be only for LR, so if my mate in his Cruiser came unstuck with a fault, I could not help with my GAP. I know the Toyota blokes say they never do, but maybe one day! I am not even sure if I had a GAP IID I could help a fellow LR with a different VIN.



I appreciate any feedback on the battery issue and the GAP IID as I am in a dilemma and need to work out the right argument to convince myself that the GAP IID is the answer, although from everything I read it seems the only way to go. I know I can take it in to the service centre to get it reset, and this may be my justification to buy!

[Tins]

I think I did something stupid and looking for advice. My 2014 Discovery 4 popped up with a low battery start vehicle warning. Car had been standing for 3 weeks so I was not overly concerned. Just popped on the CTEK and left it overnight. In the morning the charger indicated fully charged, but still had the low battery warning. Check battery voltage and it was 14.2V (vehicle off) so seems fine.


I then did some research (AULRO and Google) and discovered that you must never charge the D4 battery directly on the battery terminal - always connect the negative to the body. It seeems that if you do connect directly to the negative pole (which I did), the BMS (Battery Management/ Monitoring System) sees an "overcharge" of the the battery and the only way to resolve this is by recalibrating with the GAP IID.

I read this interesting and informative article which I think is great information for the dummies like me to get some insight on the operation of the BMS on the D4.
Battery, BMS & charging – Discovery 3 / 4 – ExpeditionParts / DiscoveryParts (https://www.expedition-parts.de/en/batterieprobleme-beim-discovery/).


This gets to my actual question regarding the GAP IID - can you reset this type of fault with someone elses GAP IID or does it need to be the one that is VIN linked to your vehicle. My biggest reservations about spending the large amount on the GAP IID are:


My budget is limited, but do love my D4, and do understand the value of being able to read and reset codes.
I can see that owning the GAP IID would already save me given my battery isue described above.
I am not a "super user" and really not the sort to service and maintain my own vehicle, although I have a reasonably good understanding of mechanical / electrical issues and tinkering is fine. It is therefore hard to justify the cost for such limited use.
I do see the benefit of being able to reset codes if you get stranded, but think there are cheaper units that can do that.
I would like to invest in a diagnostic tool that I could use to help fellow motorists out of grief, or at least read and reset their codes. My understanding (limited) is the GAP seems to be only for LR, so if my mate in his Cruiser came unstuck with a fault, I could not help with my GAP. I know the Toyota blokes say they never do, but maybe one day! I am not even sure if I had a GAP IID I could help a fellow LR with a different VIN.



I appreciate any feedback on the battery issue and the GAP IID as I am in a dilemma and need to work out the right argument to convince myself that the GAP IID is the answer, although from everything I read it seems the only way to go. I know I can take it in to the service centre to get it reset, and this may be my justification to buy!

I don't own a L319, although I covet them, so my opinion may not be of value to you, but i've been around this forum long enough to know that this probably wouldn't be the only time you would use the tool. I have a D2 ( far less complex ) and a Nanocom. I don't pull the Nanocom out everyday, but I'm glad I have one.

I have no idea about VIN specifics.

[loanrangie]

You can only perform basic code reading and clearing without adding your vin to the gap tool, yes its only for supported LR vehicles. Nancom doesn't need a vin added so someone local with one can reset your BMS.

[discomatt69]

From my understanding you don’t need any scan tool to do a hard reset which will remove any logged faults so maybe try that

[drivesafe]

Hi Netorius, try a HARD RESET.

Disconnect both your negative ( - ) and positive ( + ) battery clamps from the battery terminals, starting with the Negative first, and leave them that way for about 20 minutes.

Next, get any short length of wire and join the negative ( - ) and positive ( + ) battery CLAMPS, NOT the battery terminals.

You only need to touch them together for a few seconds.

Then reconnect the battery clamps to the battery terminals, putting the Positive clamp on first.

Then see if you are still getting the warning messages.

This procedure normally resets the vehicle's BMS.

[Gravy]

Might be worthy to peruse my post with this title. Not certain your symptoms are the same however prior to embarking on spending $$ might be worthy of a look.

Gravy

[Drafrete]

Hi, I have had this fault appear on my 2016 D4 if I charge from the battery posts. I have found if you double lock the car and let to go to deep sleep overnight after you have charged it seems to sort itself out. Has happened on a few occasions and I have never had to revert to fault clearing. Usually seeing this after charging and is a possible sign of a weak battery, I have also found.

[Netorius]

Hi Notorious, try a HARD RESET.

Disconnect both your negative ( - ) and positive ( + ) battery clamps from the battery terminals, starting with the Negative first, and leave them that way for about 20 minutes.
Next, get any short length of wire and join the negative ( - ) and positive ( + ) battery CLAMPS, NOT the battery terminals.
You only need to touch them together for a few seconds.
Then reconnect the battery clamps to the battery terminals, putting the Positive clamp on first.
Then see if you are still getting the warning messages.
This procedure normally resets the vehicle's BMS.

Good info; did this and seems to have solved the problem. I will take the vehicle in and check the battery condition anyway to be sure all is good. I wonder if the average battery centre is able to reset the BMS - I guess they must be able to.

Thanks to all for the information provided. I still need to figure out Nanocom/GAP IID.

[Netorius]

You can only perform basic code reading and clearing without adding your vin to the gap tool, yes its only for supported LR vehicles. Nancom doesn't need a vin added so someone local with one can reset your BMS.

I stand to be corrected but it looks like the Nanocom is also vehicle type specific, but not Vin specific. So if you have one for a D4, it doesnt look like it will work with a D3 or a Defender and at $800, in the same ballpark as the GAP IID. Do you think it is a better option?
Shop - NANOCOM Diagnostics (https://www.nanocom-diagnostics.com/shop/browse)

[josh.huber]

I stand to be corrected but it looks like the Nanocom is also vehicle type specific, but not Vin specific. So if you have one for a D4, it doesnt look like it will work with a D3 or a Defender and at $800, in the same ballpark as the GAP IID. Do you think it is a better option?
Shop - NANOCOM Diagnostics (https://www.nanocom-diagnostics.com/shop/browse)

Just get the gap, I went the other way, never again. If you know someone near by, just pay them the extra money to register a second vin. I lent my tool to someone on here that's local.. cost much less to just register a second vin.

[discomatt69]

Get your battery load tested, if it is sluggish and shows signs of age replace it, these cars are power sensitive and low voltage will cause constant problems, don’t be tight and think the car still starts so I won’t replace it.
I have what many would consider a good battery sitting on the floor of the shed because it started showing it’s age but would rather that and a continued run of zero faults

[LuckyLes]

Get your battery load tested, if it is sluggish and shows signs of age replace it, these cars are power sensitive and low voltage will cause constant problems, don’t be tight and think the car still starts so I won’t replace it.
I have what many would consider a good battery sitting on the floor of the shed because it started showing it’s age but would rather that and a continued run of zero faults

Add me to this list, my previous battery sits on the bench and gets charged every month or so. Very handy for testing 12v stuff. If you don't replace the battery it will let you down.
LuckyLes, the voice of experience.

[drivesafe]

Good info; did this and seems to have solved the problem. I will take the vehicle in and check the battery condition anyway to be sure all is good.
Hi again Netoruis, because your vehicle was sitting around unused for a while, before you get the battery tested, you might try this.

Scroll down the page till you get to “Battery Maintenance”
https://www.aulro.com/afvb/the-verandah/246755-line-auto-electrical-info-8.html


Just might save you the need and money for a new battery.