C Class battery drain

[Steve Taxi]

I have lived with this fault for a year now still not sorted, W203 c220cdi 51reg, the battery drains if I leave it for 2 days or more, new battery fitted 6 months ago still goes flat. I noticed that the fan in the interior light unit is running all the time, I checked it after an hour and its still running, I checked it first thing in the morning before putting the key in and its still running, could this be my problem? could someone check if their car is the same, any ideas why it is running all the time and how to stop it? cheers.

 

[panason1c]

Check if the odometer display stays permanently illuminated after locking the car...it should go blank after a minute or so ........if it remains on then it could be the canbus not going to sleep mode.

 

[Steve Taxi]

The display goes off but the a/c sensor fan keeps going, surely its meant to go off at some point

 

[alec2]

I have a w203 220cdi 52 plate.

The ac sensor fan definatly goes off when you turn off the ignition.

Cheapest soloution disconnect the fan!

Alec

 

[Steve Taxi]

Thanks for that Alec, consider it disconnected!

 

[television]

One of the processors maybe still be joined the fan is only part of it

 

[Steve Taxi]

One of the processors maybe still be joined the fan is only part of it

I see what you mean now its apart, its a big circuit board, many chips, there are 4 connections to the fan and 2 to the sensor wire, i dont want to balls it up by cutting connections.

 

[may2350]

HI STEVE TAXI
i HAD battery drain on a c270 after 3 new batterys it turned out to be the control box under drivers seat if you have one on your car pull the supply cable to it see if the drain stops.

 

[pmosi]

I have the same problem with my 2002 C320. After diagnosing the problem at the MB dealership, I was told that the power seat motor is draining my battery. Both seats. Come to find out that many other people have experienced the same problem.

I called Mercedes USA and they said that since the car is out of warranty, there is not much they can do. But if enough people call and tell them that they have this same problem, they will realize that this is a defective part and they will issue a recall and pay for necessary repairs.

Please call Mercedes USA and report this problem. 1-800-FOR-MERCEDES (1-800-367-6372) or 201-476-6200

 

[Frontstep]

I have the same problem with my 2002 C320. After diagnosing the problem at the MB dealership, I was told that the power seat motor is draining my battery. Both seats. Come to find out that many other people have experienced the same problem.

I called Mercedes USA and they said that since the car is out of warranty, there is not much they can do. But if enough people call and tell them that they have this same problem, they will realize that this is a defective part and they will issue a recall and pay for necessary repairs.

Please call Mercedes USA and report this problem. 1-800-FOR-MERCEDES (1-800-367-6372) or 201-476-6200

Are you lost ?

 

[Miffy]

Please call Mercedes USA and report this problem. 1-800-FOR-MERCEDES (1-800-367-6372) or 201-476-6200

Thanks for this, but in the main we are based within the UK and Europe

 

[television]

These ECU's fail in all the models across the range causing battery drains, its been going on for years