2004 S350 electric malfunction - Help please

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Mar 5, 2018 | 02:56 PM
  #1  
Hello guys, I’m new to all of this, but i just bought a used 2004 Mercedes s350 and this is the problem the seller described(I’m working with the seller to collect the car this weekend).

“ Sadly a fault with the computer module occurred in December and my mechanic cannot fix the issue. All functions work as normal on start up but then after around 30s to 2 minutes all the electric functions such as windscreen wipers, indicators, radio, windows, all stop working. So the car still drives but without the electrical functions operating. “

please I’m thinking is something related to a relay(overloading and disarming), something getting hot and disarming, the Battery computer module sensing not enough charging current and shutting off electronics(so the alternator could be bad), could be the SAM module(don’t know which one), but i really need your guys expertise to help me identify and fix this as quick and especially as cheap as possible.

Thanks everyone in advance
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Mar 7, 2018 | 07:03 PM
  #2  
Quote:
Hello guys, I’m new to all of this, but i just bought a used 2004 Mercedes s350 and this is the problem the seller described(I’m working with the seller to collect the car this weekend).

“ Sadly a fault with the computer module occurred in December and my mechanic cannot fix the issue. All functions work as normal on start up but then after around 30s to 2 minutes all the electric functions such as windscreen wipers, indicators, radio, windows, all stop working. So the car still drives but without the electrical functions operating. “

please I’m thinking is something related to a relay(overloading and disarming), something getting hot and disarming, the Battery computer module sensing not enough charging current and shutting off electronics(so the alternator could be bad), could be the SAM module(don’t know which one), but i really need your guys expertise to help me identify and fix this as quick and especially as cheap as possible.

Thanks everyone in advance
I feel for ya! Chasing electrical gremlins can be one of the most expensive parts of owning these cars. This is especially true if the owner or an unqualified mechanic simply throws parts at the problem until he hits on the solution. Personally, and I know you dont want to hear this, but I would run away from this particular car as fast as i could. Sadly it sounds like you and the seller have exchanged the funds so you may be stuck with it.
If that's the case, this situation is THE BEST justification for taking this car straight to a well respected dealer and letting them diagnose the problem. It is entirely likely that there are several issues not just one causing the gremlins. No, the dealer diagnosis will not be cheap, but it will be cheaper than guessing or trying to offload a car that will not pass a safety inspection (no wipers) and perhaps cannot even be registered legally.
Best of luck with the car.
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Mar 17, 2018 | 05:02 PM
  #3  
Everything it’s working again.....
ok guys, after two days with my sds in hands, I’ve sorted the problem....before i got the SDS I’ve traced and replaced the fuses and relays for the dcm’s, instrument panel and wipers always checking my 5v signal route....replaced the passenger door dcm and erased all stored codes.....and voila...all works again, now i just have a pre-safe inactive warning that I’ll sort it out tomorrow, just got back inside and decided to update this post before going to the shower and hitting the bed. Any suggestions about the pre-safe inactive warning is welcome. Thanks again Everaldo for all the help. Now I’ve a SDS if someone around me needs a hand.
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