1994 e280

Hi,
I own a 1994 e280, it has an intermittent problem with starting. I have had an electrician look at it, and £350 later he said had found the fault. He replaced a relay under the bonnet, but it still has the occasion to be "dead on the key". What I mean is all electrics light up, new battery fitted, nothing on the ignition.

What is weird is, both recent times it has been very wet out, I popped the bonnet (don't know why as I haven't a clue) closed it, got back in and it started as is nothing had happened.

This is happening more and more often, would not start last night, went back to it this afternoon, nothing on the key, popped the bonnet (again don't ask me why) and it ****** started!

is there a common fault on these? what if anything should the next expensive auto electrician start with this kind of fault?

Love driving my merc but I need it to start as I use it for work.

Any ideas would be helpful.

Thankyou

 

Long shot .... I had something similar on my E220 and it turned out to be a corroded wire running from the battery +ve to the ECU. Movement would assist in making the connection.
I opened a thread here about it.

http://forums.mercedesclub.org.uk/showthread.php?t=77032&page=2

and

http://forums.mercedesclub.org.uk/showthread.php?t=77158&page=3

 

Do you have ignition lights when this happens or just battery and srs?

 

I guess the banging of the bonnet on closing is jolting a failed solder joint on a circuit
board or jolting the fuses in their holders.

Rain caused my electrics to go faulty during my early ownership of my 124 approx
10 years ago.

Pulled into side of road and twisted all the fuses in their holders, and no problems since then, but fuses were subsequently replaced a few weeks after the event.

 

Do you have an alarm switch half way along the bonnet on one side? Is the immobiliser at fault?

Nick Froome