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Discussion Starter · #1 ·
Problem started 3 month ago, have in mind I live in sweden , minus degrees out side ,i’m on my way home from work, and the car suddenly turns dead. And I could not re-start the car. Nevertheless I managed to get the car home parked (outside).

I could not even turn the key around.... I started to investigate why

The car stood outside for couple of weeks, it was cold out side so I did not spend so much time for the investigation...
I tried to start the car every morning on my way to work, but could not turn the key around.

One morning I charged the battery whitout any improvment...
I called MB, was told that the battry it self could have a short curciut...
so I changed of battery BUT No change
I called MB
Your key could be worned out
So I got a new key BUT No change
I could not start the car....

Now few month later when it is warm out side , I went out and started the car.... like I never had a problem. So off I went, on the highway once more the car suddenly turn dead.. without any warning lights.. and a few seconds later the car re-connects, and then it drops dead, I had to pull to the side. A few minutes later the car started like the problem never existed. I took the car to my garage...

I have checked all relay’s and checked all the fuses... but the problem still existst. When it’s realy bad you can not turn on the key (gets wors when it’s cold out side). But some time you can turn the key to the “ignition position” but suddelny all lights goes away. Loss off 12V, an electrical problem.

(per defult there is 12V connected to some of the fuses , when the key is turned to the “ignition position” then 12V are pulled to the other fuses)

so by “forcing on 12 V from the battery to the fuse position 37” the key is easly turned around. And the car starts and the problem is solved.

(fuse 37 is one of the fuses that gets connected when the key is switched to “ignition position”, but you can use other positions that are not connected per default)

I belive I have a short circuit some were,,, but I puzzled that I easly can override the electrical problem by forcing on 12 V solving the “cold start problem fenomena” and also the electrical problem”

But the root cause I have not managed to find...

Any one any Idees!!!
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