Instrument Cluster Causing Battery Drain

[tmehmet]

Hi,

I wonder if anybody has had the same problem I am having and can give some advise.

I have a W203 C200K and have a battery drain problem, if I dont use the car for a day or so the car doesnt start and needs to be jump started.

I bought a new 100ah battery TWICE so definately not the battery itself but something is drainging the battery overnight. I conducted a few tests to try and narrow down the problem. I done this by using an ameter on the battery and removing fuses one by one. It turned out that while the car was off the most amount of drainage was coming from the fuse for the instument cluster. I changed the fuse (knowing this wouldnt resolve, but for the sake of it) and I am still suffering the same drainage problem.​

Can anybody help advise.​

Many thanks in advance!!​

 

[Baron_Samedi]

Does the cluster function normally?

 

[Diesel Benz]

It could be some other control unit on the same CAN bus with the cluster that keeps the bus awake. Seat controllers being popular. I think you should try pulling fuses until you can find which single fuse would bring the quiescent current to an acceptable level (assuming there is only one control unit causing the problem).

 

[richard]

The cluster stays powered up for a few mins after igntion turned off

You need to do your measurements about 20 mins after the car has been turned off (leave door & bonnet open & keys out, or it will all power up again when you open the door)


Richard

 

[tmehmet]

Thanks guys..the cluster works fine. I diagnosed the car with the door open and the key out, and pulled fuses one by one and it was when I removed the fuse that connects to the instrument cluster that the ammeter showed a respectful level..I have a feelin it has something to do with the CAN bus...gona have a friend stick it on Star diagnostics and see what it delivers...I'll let you know how I get on

 

[ABBY]

Thanks guys..the cluster works fine. I diagnosed the car with the door open and the key out, and pulled fuses one by one and it was when I removed the fuse that connects to the instrument cluster that the ammeter showed a respectful level..I have a feelin it has something to do with the CAN bus...gona have a friend stick it on Star diagnostics and see what it delivers...I'll let you know how I get on

Hi
The most common problem of battery draining is the electrical seat controller which is found underneath the drivers seat. when it doesnt shutdown it draws aprox 650 ma. it costs about £185 from MB dealers.
cheers
Abby

 

[jaymanek]

I think you may find its your iginition switch..

Get it on a star as you can see if its actually shutting down once the key is removed.. I have had 2 cars where the igntion switch does not tell the car the key has been completely removed...this would also explain why your IC remains powered up.

 

[BlackC55]

A Star won't tell you diddly about a current drain.

You need to wait until 30 mins after the ignition sw it turned off and the doors are shut and locked.

Expect 0.06A and below on a 203.

 

[jaymanek]

The star will show you the actual values relating to ignition switch and whether its shutting down when the key is removed...
quite useful