I noticed a day or so ago the ESP, 4 way flasher and headlight switch were inop. Doing some research online I checked fuse 18 under the hood and it appeared fine. I even replaced it for good measure.



I also disconnected the batter for a bit to try and clear out any fault.



From my research is could be a SAM fault. But i'm curious is there anything else I can check before bringing it into the shop?

 

Heated seats are also not working.

 

test driver seat controller

 

If the seat controller was bad, would the seats stop moving?

 

Yes that could be, there are mutiple power output channels
Each front seat has an individual controller.
Check the heater resistance + harness integrity

Now considering the fault collection in your car,
the lower control pannel may not work or network
In that case Seat module never receives a control message!

Scan the car for DTC, look at available live seat data

Faulty modules may not be listed ie. "no fault" reported!

Hope this helps,

 

The rear sam controls the lighting, pretty sure it does the seats as well. None of these issues in combination are common. You're going to need to take it to someone who knows MB very well. If you try to throw parts at it you'll easily spend more than just diagnosing and fixing one issue. I'd atleast look at the rear sam in the trunk, check and make sure the trunk sealing area - has push rivets. I see them missing frequently from body shops repair things and water will drip straight onto the rear sam if the one above it is missing.

 

Yes, there are better ways to learn about a problem than through parts at it.

90% chance the Rear SAM is out of question considering ESP, flashers, headlights. The combination of front end faults speaks for itself.

Personally I'd say you can focus on your front end issues. I don't see the R-SAM involved with that... what am I missing ?

 

I think you ignored the part where I said the rear sam controls all the lighting, it sends signals to front sam to tell it what lights to use etc..., and also provides power to the seats and the heating function, not to mention battery management, multiple 15/15r / 30 etc....circuit signals. It's about a 99% chance that you need to look at a wiring diagram and you have little if any experience with each individual system much less how they inter-connect. The seat control modules have nothing to do with the seat heating function. They don't even plug into the seat control module or pass thru it.

Considering multiple failures at the same time and the system randomness there's a good chance they just washed their car or got water entry somewhere. However this is just a guess but it's clearly much more complex than a simple common part failure, which is why I suggested professional assistance. But it's easy to look at the rear sam and see if it's covered in water / rust, large hole allowing water entry from outside to inside. A normal generic european auto shop will likely struggle to figure this out this problem.