W204/ W205 Auxiliary battery malfunction?

[RobK]

Hi all,

My Dad has a C220 CDI, Sept 2014. The logbook says "type 204" so we'd assumed it to be a W204, more research has pushed us towards it being a W205.

We've both previously had W211 E classes and worked on them ok.

I've researched this aux battery malfunction and it sounds like it's a small module under the passenger side carpet that will be at fault as I don't think he has an Aux Battery installed (we've had a good look)

The malfunction came up in red, then turned white, then disappeared and is now back!! Car runs fine, I've asked him to disable the stop start function until we get it sorted.

Any help/ advice appreciated.

I have a part number for the capacitor/ voltage converter that could be to blame. Anyone had anything similar? Tried to search but nothing came up.

Thanks, Rob

 

[John Laidlaw]

Welcome Rob. In 2014 it could be either a 204 or 205, if your log book says 204 I'd reckon that's right. Another way to check is on the Windscreen VIN number display which will start with a 'W' then embedded in the first few digits you'll see either 204 or 205
I see the car has got stop/start?....
Anyway it's likely I think that you do have an Aux battery and it's likely to be in the engine compartment under the(cabin) air filter housing