500sl asr & ABS light

GOVNARI

MEMBER
1992 MERCEDES BENZ 500SL
V8
2WD
AUTOMATIC
74,000 MILES

ASR light along with the abs light right next to it go on and the RPM's run up to 10,000. It can happen while I am on the freeway, or in traffic, or once I shut the engine down, and then start it up a few minutes later, it will come on, it will go off just as sudden. The car will die every so often when I make a stop.

1 Reply

FIXITMR

MECHANIC
9,990 POSTS

You could try this. Everything was OK for a couple of weeks until the warning lights came back together with the high idle. Tested the OVP relay as previously, cleaned the contact pins and socket with contact cleaner but this time no change when I re-installed it. With nothing to lose I decided to take the relay apart and clean the actual switched contacts inside, which turned out to be very easy. Bend open the two aluminium can tabs on the relay base, insert a small screwdriver either side and lever the base plus relay assembly out of the can. I used a thin folded piece of 2000 grade wet and dry paper to clean the relay contacts and checked the printed circuit board for any dry joints - all looked OK. Before you re-assemble, clean and gently bend closed the two Y shaped contacts on the top of the relay - these connect to the 10amp fuse on top when you slide the relay back in the can. I didn't tighten these the first time I re-assembled and the fuse contact was loose and showing a high resistance connection. This time, when the OVP relay was re-installed the warning lights were out and the idle back to normal. I'm hoping that the repair will last a bit longer now that the relay contacts are clean.