C Class dead and wont take key

[airbag]

Hi, I have left my 2002 S203 for 2 days and now key wont open car, nor will ignition accept either of my key fobs.

Does this sound like a flat battery issue? Both key fobs show red lights when pressed so think their batteries are ok.

Thanks for any info.

 

[Xtractorfan]

You can check if the battery is dead by switching on headlamps, interior lamps etc.. if so recharge the battery, tho if it has gone flat in 2 days it would seem you have something drawing power from the battery....you sure that lights etc werent left switched on?

 

[television]

You could turn the headlamps on, and that will tell you if the battery is flat

 

[airbag]

Hi, Yes the Battery is dead.
I have borrowed a volt meter and the battery is dead, but takes a healthy charge, also the alternator is charging ok.

There is a drain of 2.5 Amps from the battery, this is happening even after 15 mins of the car being locked. I also have an ESP error showing on my dash when I start the car up.
Could this error be causing a drain on the Body Control Electronic System? and hence draining the battery?

Strange the two things have happened at the same time.
Thanks if anyone has any experience of this error or any info

 

[5pares]

The light is caused by the low voltage and probably isnt the battery drain.

 

[bigasotonuk]

Hi,
If the power is interrupted to the car ie disconnection of the battery (in your case a totally flat battery) the ESP warning light will be on till the steering is turned from lock to lock, so the chances are if you were to do this it would be extinguished.
Regarding your battery i would start by removing all the fuses in the car and introduce them back till the drainning circuit is located.
Has your car got COMMAND? as i believe these can sometimes cause a battery, but 2.5A does seem a bit high for this to be the culprit.

 

[television]

Just turn the steering from lock to lock and the ESP lamp will go out.

2.5 amps is a high drain, that is some 30watts, as Andy said take out the fuses one by one and you may find that cause of the drain. The Comand will not be the fault though, more likely a seat controller or a SAM fault

 

[airbag]

Hi Guys, thanks alot for ESP and the fuses tips.
I will try that and see if we get anywhere in locating this drain.

Is there any fuse guide on the net you know of? One that shows main fuse locations and correct fuse amperage for each slot?

 

[television]

Hi Guys, thanks alot for ESP and the fuses tips.
I will try that and see if we get anywhere in locating this drain.

Is there any fuse guide on the net you know of? One that shows main fuse locations and correct fuse amperage for each slot?

Have you checked to see if the fuse location diagram is not in the tool kit or in one of the fuse boxes

 

[airbag]

Hi Malcolm, Thanks.. I did find it folded up, and tucked away in the front dash fusebox.

 

[Hertfordshire Merx]

Door control modules and as previously mentioned seat control units are a good place to start with excessive quiescent drain issues. However I have had many dealings with issues like this and they can come from anywhere.

Do you have any accessories fitted to the car particularly non Mercedes ones? If so I would disconnect those first.

An acceptable drain is anything below 40 milliamps, so thats your aim!

Good luck.

 

[airbag]

Hi Guys,
I got an ammeter onto it, and it now was pulling 1.75amps drain with my new meter (was 2.5amps with the AA mans) .. so I did the following.

First of all took out the disk from the COMAND, then removed the COMAND Fuse, this bought it down to 0.95

Then I removed the 3 fuses from the Driver Electronic Seat Controls (2 near dash and one in rear). This bought it down to 0.15.

I then put COMAND fuse back in (bought it back to 0.28), and started to introduce one fuse at a time until I found the culprit! It is one of the 30A fuses in the drivers dash fuse box (#27 the lower 30A one).

Thanks to you all for helping me diagnose this issue (and to Shane from MB Tech for the phone support
So I wanted to ask, where to from here? Is there a module or relay for that seat that maybe needs changing? Is this a part you can purchase and I fit myself?

 

[television]

Yes you can change this your self and it is the most common fault. We should have warned you that the comand take 20 odd mins to go to sleep.

Withe the first 6 vin numbers I can give you the fitting instructions and location, though probably in the doors.

Some folk cut the memory wire and join it to the + wire to save buying a new controller

 

[airbag]

Hello television,
thanks alot for your reply.

WDB203 is what is listed on the sticker on inside drivers door. Is this it?

 

[television]

Hello television,
thanks alot for your reply.

WDB203 is what is listed on the sticker on inside drivers door. Is this it?

Thats fine,,i need your Email address please and I can send you the door panel removal instructions and those for the module.

What you must do then is to unplug the control unit then re check the current drain to confirm

 

[airbag]

Thanks Malcolm, I have PM'd.

 

[television]

Both papers sent and as said do double check once it is unplugged, MB parts only, they often get water in them,,

 

[airbag]

Malcolm, thanks alot!
Just to confirm... that module in the door does the seat controls?
does it just do that or the doors as well?

 

[television]

They do as far as I know, and all cars that have the switches in the doors for the seats are the same, they also control the mirrors

 

[airbag]

MB gonna charge £148 for 1 x door control module!
...geez, Think I will just leave the fuse out!

Anyone know of aftermarket parts?