adamski.

Hi there, I have just stumbled across your discussion relating to the intermittent fading of the C32 instrument cluster.
I am having the same issue, but with the addition of a battery drain if the car is left longer than approx 8 hrs.
I have had need to install a kill switch at the battery to isolate it because nobody can work out where the fault is. So I'm going to see if I can trace it ...

I have recently noticed the alarm siren making an intermittent 'crackling noise' when I turn the isolator back on, but without the ignition on. This coincides with the instrument cluster fading....

I have also noticed a very slight background 'hum'all the time when the ignition is off. It sounds like a fan is still running slightly.

Also, the passenger electric seat has stopped functioning, which is think is the module. The headrest adjustment failed first followed by the rest of the seat motors.

I am on my second battery and last year three referbished alternators cooked. 'Fingers crossed', this current alternator is holding strong...

I would really appreciate any help or advice on disconnecting the alarm siren or replacing it, or the fuses I need to pull so I can check that it's at fault first?

If anyone has experience or can help with any guidance with any of these issues it would be really appreciated...

I can't find much posted specific to the questions and issues I have. So I'll keep writing on here with any updates just in case some other poor sod who is experiencing the same things is reading who may find it of some use.

adamski.

...

froggyAMG

Did you try to unplug driver and passenger seat module ? Known to drain battery.
A simple solution to solve it ! => https://mbworld.org/forums/c-class-w...drain-fix.html

Bigpapistu

Try disconnect your seat modules underneath your front seats. If your battery doesn't drain you need new modules. Really common problem on a lot of c32's/c55's. MB should've really done a recall on it but oh well..

Baz440

I had same bother my rear interior light wasn't working so I replaced the fuse and the battery drain started, not every day just sometimes. Took the fuse back out and so far so good it's not happened since. Might be worth pulling the fuse in the boot for the light cluster.
Baz