For the past few weeks, the door handles have not been extending and retracting automatically. The problem affects the driver’s door handle and the right rear door handle. Sometimes they suddenly pop out while I’m driving.
Now there’s a new issue. I’m getting the error message shown in the attached photo:
“Electric drive system fault. Stop the vehicle and refer to the owner’s manual.”
The roadside assistance technician came out to help. The diagnostic scan showed no faults at all, except that the main 12 V battery voltage was only 10.1 V, so that’s most likely the cause of all the issues.
There is also a small 12V auxiliary battery in the arm rest, which can give various problems if it has degraded (not holding charge, etc). Maybe that was checked by the technician, but if not it is worth getting checked. I think it is a service item (changed at 4 years). Mine is >4yrs, and I am just checking the voltage every now and again, and will swap it as soon as I see a reduced voltage just to minimise any issues.
The technician measured it first through the diagnostic system and then physically with a battery tester connected directly to the terminals of the main 12 V battery under the hood, near the engine.
At first I also suspected the small battery inside the center armrest, but it turns out that’s probably not the one.
How do you measure the voltage of that small battery? How do you access the small battery inside the center armrest?
Underbonnet battery is lead acid (typical car type), the one under the Armrest is an AGM type and should be good for 4-5(+) years.
As I understand the way the system works, the engine charges the main battery, then when that’s upto a certain state of charge, it charges the armrest battery, IF the underbonnet battery is not getting upto the threshold, then the other will never get charged.
The beauty of AGM* batteries is they are quite happy going from a high to low state of charge without any issues. So, now you have had the underbonnet one replaced, run the car for a few days/weeks and check the other one.
Checking, I don’t know how others do it, but I have a simple one battery minder ( trickle charger) and that I connect occasionally, my charger also has the function to give me a state of charge (SOC) and state of health (SOH).
To get to the terminals of the small battery in the armrest, take out the rubber mat inside the armrest storage, under that is a plastic cover with four clips that you press inwards (just use fingers) to allow it to be lifted out. The battery terminals will then be exposed. I think if you need to remove the battery, then you have to dismantle the armrest - I am sure there is a post on here that explains that.
I just check the voltage on the battery with a multimeter as that is all I have, but something that shows the SOC/SOH would be better.
Just been to have a look, and there isn’t any label that I can see without removing the battery. I am sure somebody here will be able to advise on the main battery specs
From past experience
I’ve had 5 main batteries fitted and 1 armrest battery, all under warranty in less than 2 years.
Also I dont think your sticking door handles are down to the batteries, if it were they would all either not work at all or all stay in the out or in postion.
Again this is from my experience, I’ve had all 4 replaced under warranty in the past 2 years.
Your issue with the handles is more likely down to the known fault of water ingress into the handles sealed mechanism unit.
My guess is you have two separate issues.
Low 12v battery, either the main or armrest , but could be both.
Then you have the known sticking handle fault.
Welcome to DS .
Yesterday I changed both batteries. Problem with handles is still there. I am in Croatia and they say around 500 euros per handle🫣. So I will have to change them. Thanks for your help
Are you a tinkerer, I had a car where the rear door lock would only work from the inside.
Non tinkerer = Spray oil into the handle pivot points/mechanism to free it up keep locking unlocking your car to activate the handles.
Tinkerer = Remove the handle , clean and lubricate, refit.
Good luck, it’s possibly a little road grime in the mechanism.
As I mentioned.
The sticking handles is a fault by itself.
The 12v batteries are a separate issue.
Unfortunately as you found out, changing the batteries did not solve the sticking handles.
When the 12v batteries cause issues with the handles, they dont stick in or out or halfway, they just stop working.
Another thing to mention is that the handles will stop working if :
You unlock & lock too many times but dont actually open the doors and drive off
Walk past the car too many times and they pop out and back in (proximity feature), but again dont open the doors and drive off.
Both of these is a battery saving feature, you have to the drive the car for a certain distance to put charge back into the battery before the handles work automatically again.
This is a totally separate issue to the handles sticking.
This sticking is because of water ingress into the handle mechanism.
My local car accessory shop sells a fine maintenance spray. Any fine spar oil will do, get one with a straw on the end so you can direct it carefully .
Not Wd40 as that evaporates.
After seeing the sealed mechanisms location behind the handle I doubt a spray would find its way in to the unit.
Also theres some electrical components inside the unit that corrode and sometimes cause the handles to intermittently try to open/close whilst driving.
Removal of the inside door card/panel, and then locating the unit/handle , open it up, give it a good clean and the close and reseal is the only option.
Or pay for an expensive replacement.
