W219 battery drain, no radio and overall weirdness
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W219 battery drain, no radio and overall weirdness
Heya guys!
I made an account here and hope you guys can help me out.
I bought a cls from 2005 and it's been a headache.
The car has had water damage and the main modules had to be replaced for that. After that it has been experiencing battery drain.
These last couple of days I've been trying to find where the issue is but can't seem to find the problem.
The head unit on startup shows the Mercedes logo for a couple of seconds then turns of. I think this has to do with a module that's also causing the battery drain but i've yet been able to find out what module this is.
I've tried placing a fiber loop on multiple easy to reach modules to no avail. I also placed one on the head unit itself which didn't fix it.
Yesterday when trying to find out how much battery drain there is i placed my multi-meter in series on the battery and waited for about 45 minutes.
The drain went down to around 0.1A after which it suddenly spiked to 2A and the car started acting weird.
Lights started turning on and of. Errors started showing on the screen. Handbrake light started flickering SRS started turning on and off.
Even the headlights were turning on and off.
After driving it for a while these problems disappeared again.
Let the car sit overnight and the battery was at 11.98Volts.
It has not started acting possessed this time.
I want to try and see if its the AWG module but before i rip everything out to get there I'd like to hear your opinions.
Before i bought the car it had been send to a shop who tested the alternator. According to them there's no problem there.
Another thing I've noticed is that my seat heaters don't work. Not sure if that's related or if they just need learning.
I made an account here and hope you guys can help me out.
I bought a cls from 2005 and it's been a headache.
The car has had water damage and the main modules had to be replaced for that. After that it has been experiencing battery drain.
These last couple of days I've been trying to find where the issue is but can't seem to find the problem.
The head unit on startup shows the Mercedes logo for a couple of seconds then turns of. I think this has to do with a module that's also causing the battery drain but i've yet been able to find out what module this is.
I've tried placing a fiber loop on multiple easy to reach modules to no avail. I also placed one on the head unit itself which didn't fix it.
Yesterday when trying to find out how much battery drain there is i placed my multi-meter in series on the battery and waited for about 45 minutes.
The drain went down to around 0.1A after which it suddenly spiked to 2A and the car started acting weird.
Lights started turning on and of. Errors started showing on the screen. Handbrake light started flickering SRS started turning on and off.
Even the headlights were turning on and off.
After driving it for a while these problems disappeared again.
Let the car sit overnight and the battery was at 11.98Volts.
It has not started acting possessed this time.
I want to try and see if its the AWG module but before i rip everything out to get there I'd like to hear your opinions.
Before i bought the car it had been send to a shop who tested the alternator. According to them there's no problem there.
Another thing I've noticed is that my seat heaters don't work. Not sure if that's related or if they just need learning.
