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Danwilderspin

Member Since: 15 Jun 2016
Location: Cambridgeshire
Posts: 2282

2007 Range Rover Vogue SE 4.2 SC V8 Zermatt Silver

Which battery is low?

So if o leave the car a couple of day it says after 30 seconds or so of the ignition is in - low battery start engine. Go for a drive it goes away unless I leave it sitting.

My question is which battery is low of my two how can I check? Current stable:
2015 5.0 V8 S/C AB
2006 BMW M6
2007 4.2 V8 S/C FF
Gone:
2002 4.4 V8 FF

6th Oct 2025 9:42pm

Kot

Member Since: 10 Mar 2021
Location: Broadland
Posts: 1434

I usually just put the ctek on when this comes up usually every 2-3 months. They are power hungry beasts. 2018 SE SDV8 4.4 Byron Blue

7th Oct 2025 8:47am

sullivj

Member Since: 19 Jun 2025
Location: Gatwick
Posts: 53

2014 Range Rover Autobiography SDV8 Santorini Black

Mine kept coming up with the same warning. I replaced the main battery under the spare wheel, reset the BMS and I've not seen the warning since. Mine is 2014 without start stop.

I fitted this one, which Europarts gave me under warranty as my previous one was 2.5 years old and showing signs of weakness - result!

https://www.eurocarparts.com/p/exide-agm-s...-444777006

Last edited by sullivj on 11th Oct 2025 5:14pm. Edited 1 time in total

7th Oct 2025 9:00am

Haylands

Member Since: 04 Mar 2014
Location: East Yorkshire
Posts: 8822

2014 Range Rover Autobiography SDV8 Loire Blue

The jump connections on the drivers side of the engine bay are connected direct to the main battery, measure the voltage there, if it's around 12.6 30 mins after charging then it's the second battery, if it's low then the fault lies with the main battery.... Pete
__________________________________________________
2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
-Click here for Thread-
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand Sold
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Sold
2002 L322 Vogue 4.4 V8 Epson Green (Fatty Offroader) Sold
-Click here for Project Fatty off roader-

7th Oct 2025 9:27am

stan
Site Moderator

Member Since: 13 Jul 2010
Location: a moderate moderated moderator moderating moderately in moderation
Posts: 35862

when i was researching my stop/start disable i'm sure i read in the WM that the aux battery is a 'fill in' for the stop/start system..

i reckon its your main battery Dan....

disconnect the earth on the aux battery and see if you still get that message. ... - .- -.

Y. O. L. O.
.

7th Oct 2025 10:21am

Bardley

Member Since: 01 Jan 2025
Location: Hertfordshire
Posts: 57

2014 Range Rover Autobiography SDV8 Corris Grey

Or get both checked on a proper tool that'll give you a state of health.
Plenty of these are available on the usual sites.
Search TopDon. L405 2014 SDV8 4.4 Autobiography
Corris Grey
Previously 2011 D4 SDV6 HSE Santorini

7th Oct 2025 5:13pm

Danwilderspin

Member Since: 15 Jun 2016
Location: Cambridgeshire
Posts: 2282

Ok going to check the 12.6 first - does the little battery need coding? Current stable:
2015 5.0 V8 S/C AB
2006 BMW M6
2007 4.2 V8 S/C FF
Gone:
2002 4.4 V8 FF

7th Oct 2025 8:24pm

hmallett

Member Since: 21 Jan 2024
Location: Mid-Wales
Posts: 155

2013 Range Rover Autobiography SDV8 Firenze Red

Re: Which battery is low?

Danwilderspin wrote:
My question is which battery is low of my two how can I check?

I can tell you that in my case it only appeared when the main (under the boot floor) battery was low. The reason I know this is that my auxiliary battery was knackered, with the BMS reporting it as permanently at 0% state of charge, and I didn't get the low battery warning all the time.

7th Oct 2025 9:26pm

hmallett

Member Since: 21 Jan 2024
Location: Mid-Wales
Posts: 155

Danwilderspin wrote:
does the little battery need coding?

Rather than seeing it as coding, it's a case of resetting the BMS' battery statistics. So when you fit a new battery, that reset means that the BMS starts learning the values for your new battery from scratch.
I believe that if you don't reset the BMS, it'll be fine, but I guess maybe it'll take the BMS longer to learn the characteristics of the new battery.

7th Oct 2025 9:32pm

Harry858

Member Since: 02 Mar 2025
Location: San Diego
Posts: 3

I thought the start/stop uses a super capacitor and no longer a battery - so that would be your main battery. It's always on if you have the connected services (remote start/AC/unlock/alarm/monitroring...etc...)

11th Oct 2025 3:55pm

stan
Site Moderator

Member Since: 13 Jul 2010
Location: a moderate moderated moderator moderating moderately in moderation
Posts: 35862

it does on FF's after around 2015...

pic of the vqm

... - .- -.

Y. O. L. O.
.

11th Oct 2025 4:10pm

JamboM3

Member Since: 28 Jul 2021
Location: Berkshire
Posts: 273

2019 Range Rover Autobiography 2.0 PHEV Indus Silver

My 2017 AB had a full size AGM as the auxiliary battery.

Unsure if applicable to all years but do not think aux battery is monitored in the same way as starter/main battery hence it has no BMS on it. So likely the main battery needing charging/replacement

12th Oct 2025 1:09pm

sullivj

Member Since: 19 Jun 2025
Location: Gatwick
Posts: 53

My 2014 has a second battery. When I plugged in my diagnostic tool, it gave me the option of resetting the BMS for both batteries.

12th Oct 2025 2:13pm

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