Hi

Looking for some help bringing an old girl back to life. I bought an e200 w211 3 years ago and drove it non stop for 2 years. I occasionally got low voltage electric consumers switched off message but never really did anything about it because everything seemed fine.

She has been sitting up for the last year not touched due to various different reason so i decided to get it back going again recently.

Battery was dead with no volatage so i change that and i was getting the error message check battery check alternator check breaks with lots of beeps and flashes.

I changed out the whole alternator and then only message i was getting was check battery / electric consumers switched off. Picked up a new aux battery and fitted it. And apparently that fixed everything.

No error messages, everything fine. Car running smooth. Took it for a spin, blew out the cobwebs. Eventually stopped for petrol. When i got back in the car after filling it up i get the red check battery error electric consumers switched off.

I parked it up and unplugged both batteries. The next day i connected both batteries again and everything was perfect. Drove it around the block, left it along for 30 minutes and came back and again electric consumers switched off and red battery error.
I left it over night with both batteries connected. Came back this morning and it started on first key turn but again still has the red battery error electric consumers switched off.

I haven't checked the voltages on the battery's with this red battery error, my mate is bringing me a multimeter tomorrow

Any ideas ? Aux relay ? some fuse? corroded earth wire somewhere? BCM ?

Thanks for reading

 

Did your friend ever bring over his DMM? The aux battery may not be getting charged.