Summary: LR4 SDV6 2011. Driving along I get HDC not available, DSC not available, EBA not available, AB fault, gearbox fault, Suspension lowered for safety, normal height selected, fuel low, fuel gauge doesn't work, speedo doesn't work, park brake fault, HDC system error, charging system fault. Then the check engine light comes on and the car is stuck in 3rd. Stop, restart - all OK. Probably a few more but all this inside two miles max after driving around 5 miles.

Battery new, hard reset done, brake switch changed (since this seemed to be a common source of this).
The car has done 42k, is always garaged and dry and has no corrosion . The wheel sensors are OK according to the IID Tool live values.
Has anyone got ANY ideas at all?
I have checked all the cables I can and there are none loose and no corrosion signs - the car is essentially new.
I have a list of OBD faults but I am not sure they are much use. They are all U codes except

B11DB-87 (28) Battery monitoring module - Bus signal/message failure - missing a message
( on 18-01-2022 14:14:03 at 61602 km )

this occurs many minutes after all the other faults so I am not sure it is a root cause.

 

We’ve seen multiple reports of similar behavior on this and other forums, but I can find the threads right now. My recollection is that it usually is the charging system. I realize your battery is new, but have you checked the alternator? They can fail with no apparent reason, but if you have (or had in the past) a valve cover leak on the passenger side, that can shorten the life of the alternator as well.

 

I thought I had fixed this by installing the new battery and resetting the BMS but no - after 10 miles I have all the warning lights once more....

ANY ideas?

 

As I mentioned above, did you check the alternator?

 

Sure. Sorry for not posting it. It is pumping out between 60 and 105 amps at 14.6volts.
Could it be a regulator or BMS cable issue?

 

Actually, today it was worse than before. Before I needed to drive, get the errors, stop and restart. Now I get the errors after switching the ignition on for 15 seconds and sometimes it takes 3 minutes for the ignition to wake up.
I am going to charge the new battery overnight and see if this makes a difference

 

You can just check the voltage at the battery at rest to see if the battery is low. You should see at least 12.6v (pop the hood and then wait about 10-15 minutes to make sure all the systems have turned off). If you’re seeing 12.6v, charging overnight won’t make any difference. If you are not seeing 12.6v, could be a problem still with the battery or alternator (12v is basically dead, 12.2 is very low, 12.4 is not great - especially on a new battery).

Could be BMS, but I’m not sure how you would test it - and I’ve not heard of others replacing this system. Could be bad earth ground strap, especially if you are in an area with lots of corrosion issues. The earth ground runs from the battery to the passenger side fender. You need to remove the wheel well liner to get access. Also check the ground on the alternator.

But, that latest bit about the ignition not waking up is strange. So, when you press the start/stop button, nothing happens - no lights or anything for 3 minutes?

 

right

 

Charged the battery overnight and then reset the BMS. It is running at 36 amps on the alternator at 25% load. Voltage is 14.5.
Yesterday it had all the warnings after one minute running. Now there are none and it has been running for ten minutes. I am going to leave it all day running to see if anything happens.
I do have the check engine light on for some reason but this is not a major issue

 

Do you know how LR would do a diagnosis if there are no DTCs and no warning lights? Do they have fancy test kit us mortals don't?
thanks