My MY19 AB is having an avalanche of problems that seem to come and go. For example:

An yellow engine warning light that I can’t clear with my GAP tool - this is on permanently
Every now and then a red restricted performance light that can be cleared by restarting the engine - this will either go away for a few days or do it two or three times before it goes away
The deployable steps don’t work - I have tried all the different fixes suggested in my earlier post
The drivers seat massage failed but then restarted and has now stopped again - this is with some other faults on the seat not moving etc.
Low battery restart engine comes on after having the boot and/or doors open for 5 minutes even after a 200 mile journey at motorway speeds
Yesterday the lower climate screen failed and then after leaving the car parked and shutdown for a couple of hours it started working again.

Does anyone have any ideas?
Could it be an earth short?
Is it battery related?

I can’t get it in to the dealer until 18th September but anything I could do in the meantime would be appreciated. 2019 Autobiography SDV8 Byron blue/black - current
2016 Vogue SE SDV8 Santorini Black/Ivory - sold
2009 RR Sport TDV8 HSE - sold

i would get that battery properly checked out..it could be the cause of your problems .. ... - .- -.




Y. O. L. O.
.

Thanks Stan 2019 Autobiography SDV8 Byron blue/black - current
2016 Vogue SE SDV8 Santorini Black/Ivory - sold
2009 RR Sport TDV8 HSE - sold

there is a second battery in 405s isn't there? I had a second battery in my 322 and it drained the main battery causing totally engine stop etc.

The 405 has a BMS system that keeps the two batteries separate until needed, apparently one flat one can't pull the other down but that's in theory...!!

It's weird that some have two batteries and stop/start and some have two with no stop/start, and some just have one...!!! Pete

__________________________________________________
2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Parchment over Navy Interior. Sold
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand, Jet Interior. Sold
2002 L322 Vogue 4.4 V8 Epson Green, Ivory over Aspen Interior (Fatty Offroader) Sold
-Click for Project Fatty off roader-

@madasmad:

Get one of these:

Click image to enlarge

Just an update -

The yellow engine light cleared on its own for the last week or so but came back again today along with the red restricted power. I checked faults on my GAP tool and got the following:
BCM-Body Control

U201B-54 (2F) Control module calibration data 2 - System programming failure - missing calibration
( on 25-08-2023 18:05:08 at 39919 mi )
- Test Failed
- Test Failed This Monitoring Cycle
- Confirmed
- Test Failed Since Last Clear
U2300-51 (2F) Central configuration - System programming failure - not programmed
( on 25-08-2023 18:05:08 at 39919 mi )
- Test Failed
- Test Failed This Monitoring Cycle
- Confirmed
- Test Failed Since Last Clear
GWM-Gateway module

B1479-08 (2 Dual battery junction box - General failure information - bus signal/message failure
( at 0 mi )
- Confirmed
- Test Failed Since Last Clear

I cleared all faults and the last one - dual battery box junction - didn't come up again.

Has anyone any idea what these faults mean and what can be done to fix them?

Did you check battery SOH, as Stan advised?
Could still be a battery or earthing issue, albeit earthing not much likely on a MY2019 car.
Better to check the simple stuff before going on a wild goose chase changing modules, etc.  “If it ain’t broke, don’t fix it” -where’s the fun in that?

Thanks Gremlin

The stealer has it at the end of next week for a week and let's see what they come up with. 2019 Autobiography SDV8 Byron blue/black - current
2016 Vogue SE SDV8 Santorini Black/Ivory - sold
2009 RR Sport TDV8 HSE - sold

So, after 10 days at LR Stafford - who have been great - they have fixed the following:

Deployable steps - software update - supplying dealer should have done this before delivery
Lower screen - software update - supplying dealer should have done this
Low Battery- multi function display no switching off - software update supplying dealer should have done this
Reduced performance - turbo actuator needs replacing (awaiting parts)
Bad vibrations when breaking from speed - the front breaks have an air duct missing on both sides and breaks overheating - original supplying dealer arguing that they will not replace!
Seats not moving - system reset

Currently sat in LR Stafford who won’t release the car until the original dealer pay the bill so far! I have been waiting 3 hours. 2019 Autobiography SDV8 Byron blue/black - current
2016 Vogue SE SDV8 Santorini Black/Ivory - sold
2009 RR Sport TDV8 HSE - sold

Gremlin500 wrote:

@madasmad:

Get one of these:

Click image to enlarge

Usually £18-£25 on AliExpress or eBay, maybe a bit more on Amazon.
Great value gadget, and will quickly help you diagnose battery-related issues.
Go for the 580 rather than the 550 which has fewer features but is often advertised at a similar price.

Bloody hell mad who is the crappy dealer you bought that from, disgraceful. overfinch modified

Hi madasmad,

I have successfully used on both, but I only have one battery!
You can but try, it’s not exactly a fortune, is it, or too much of a chore to lift the boot floor up?  “If it ain’t broke, don’t fix it” -where’s the fun in that?

It will (among many other things) tell you battery % remaining SOH (state of health) compared to new (not just SOC state of charge) -mine was a pitiful 29% last year before I replaced it, even though the car was still starting OK, -probably due to being plugged into a CTEK most of the time. It only takes a few minutes to complete a scan. If you end up needing a new battery, Tayna are very good, I got one of their own “Enduroline” AGM ones which came with a 5-year guarantee at a good price and fast delivery. “If it ain’t broke, don’t fix it” -where’s the fun in that?