Where is auxiliary battery in w213 E220d located?
- Thread starter PMCP
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GavinP
Active Member
Top of the front passenger footwell I believe
GavinP
Active Member
You will need to remove some nearby plastic mouldings and peel back the carpet to gain access to the battery area, and the fastenings can be undone with a 10mm socket. You should also disconnect the main battery before attempting the work.
Once the fastenings and the plastic cover are removed, you can take out the voltage converter by taking off a couple of small tabs. The voltage converter is also known as the capacitor, and can be easily sourced. It is a relatively common problem.
Once the fastenings and the plastic cover are removed, you can take out the voltage converter by taking off a couple of small tabs. The voltage converter is also known as the capacitor, and can be easily sourced. It is a relatively common problem.
Thanks a million Gavin. I'll let you know how I get on. Sounds like you know a lot more than me!
GavinP
Active Member
No, I have had little joy getting replies on here somI always do internet searches too. Found this Mercedes-Benz Auxiliary Battery Malfunction Explained
GavinP
Active Member
I thought the aux battery was no longer used - had one on my 2005 E320 d estate but did. To think there was one on my E400d estate - I'll take a look now. Good luck with the fix.
So I stripped the whole car down, boot, passenger footwell, everywhere basically but no auxiliary anywhere. Had another look under the bonnet and noticed that the main battery is an AGM stop start. Am I right in saying that this means there is definitely no auxiliary even though the car says "auxiliary battery malfunction"?
GavinP
Active Member
GavinP
Active Member
The old e320d had an aux battery for the SBC (sensortronic braking) which Inthink MB dropped 8-10 years ago. I don't think it is a battery anymore but a capacitor (See earlier post)
I've seen W205s with an aux battery:
And I've seen them without albeit with a "C8 Park Pawl capacitor" instead:
So my guess is they were batteries at launch and they changed to capacitors later on although I don't know which year.
Both of these things are under the carpet in the passenger footwell.
I've read that the later module is prone to failure though.
However, the car still shows "aux battery" as the error regardless of which age.
This is only what I've read so I am not 100% certain!
If you can't see a battery in the passenger footwell from what you have seen, my guess is you have a capacitor...
And I've seen them without albeit with a "C8 Park Pawl capacitor" instead:
So my guess is they were batteries at launch and they changed to capacitors later on although I don't know which year.
Both of these things are under the carpet in the passenger footwell.
I've read that the later module is prone to failure though.
However, the car still shows "aux battery" as the error regardless of which age.
This is only what I've read so I am not 100% certain!
If you can't see a battery in the passenger footwell from what you have seen, my guess is you have a capacitor...
