Cut-out problems with E220 Coupe - UPDATE (still playing up)

[Brian E220]

About 7 days ago my E220 Coupe (1995) started cutting out during a motorway run. It was random and under all conditions (acceleration, cruising and slowing down). It was just like throwing a switch, no spluttering (the ABS light would come on when the engine cut out). It would restart after a few seconds and run for a random period of time.

I have had a look at the OVP relay and it appears to be the newer version: 00 054 067 45. 2 days after the fault first developed, I found the battery completely discharged and looking like it won't take a charge at all.

Any ideas are appreciated, thanks.

 

[Andy]

Hi

First port of call is the OVP. Replace it. Then try it again.

Regards

Andy@ www.mercedesservicing.com

 

[Brian E220]

Hi

First port of call is the OVP. Replace it. Then try it again.

Regards

Andy@ www.mercedesservicing.com

Latest:

1. Battery charged and still in decent condition.
2. OVP replaced

It is still cutting out at random times - I drove around for about 10 minutes then it started again :evil:

A few more indicators:

1. When it cuts out all of the dashboard warning lights except the SRS light go out. Oil pressure and temperature gauges return to zero.
2. When turning the ignition on and off - if it is still faulty, the dash lights come on then go off (with the exception of the SRS light) and I hear a relay click from the OVP vicinity.
3. If the dash lights stay on (as normal) then the car will start and run for a random time perfectly.

It's almost as if the electrics are hit with a 'spike' and it's latching the OVP relay.

I've been looking for a wiring diagram but no luck yet

Can anyone provide any more clues, source of a wiring diagram or at least tell me what the blessed OVP is connected to?

Thanks.