1991 500SL Starting Problem

[GregE240]

Hi folks,

Wonder if anyone can shed some light on this for me?

I've just got back from a 1700 mile tour of Germany, including visits to RUF and the Schlumpf museum (highly recommended). My partner and I took the SL, and it performed faultlessly, aside from an occasional starting issue, which I thought I'd had fixed.

The problem is this: every so often, you go to start the car, turn the key and you DON'T get all the dash lights come on. If you continue to turn the engine will turn over, but will not start. You then have to turn the key back to 0 and try again. Next time it might start.....or it might not. During the trip it was mostly okay, just a little heart in mouth "will it start" moment every now and again.

I've had the sleeve that the ignition barrel fits into replaced, and this seemed to do the trick, but alas, the problem surfaced again. Another mechanic has cable tied the main ignition power feed to the switch as they thought it might have worked loose, but that hasn't done the trick either.

The problem occurs regardless of whether the engine is hot or cold.

Any ideas? I'm open to suggestions!

Thanks,
Greg

 

[stats007]

How does the immobiliser work on your car? Do you have a transponder key? Tempremental indicates a grounding fault / loose wire to me.

 

[GregE240]

Thanks Stats.

The immobiliser is built into the key, I think. Theres no separate key or anything. Its the one where if you leave the car unlocked for several minutes, the alarm chirps once, and then the car won't re-start (regardless of my problem!) - you have to lock and unlock the car in order to start it.

Dunno if new batteries in the key is the problem as it happens with both keys.

 

[stats007]

I'm not sure if your car has a starter lock out and whether it affects power to the instrument cluster - it appears to have been introduced in '93 (in the US). It runs via the relay K38 (behind the IC) - with the alarm off power is received from the ATA module.

 

[GregE240]

Thanks Stats, car is booked in with my man on Wednesday, fingers crossed.

 

[IanA2]

Thanks Stats, car is booked in with my man on Wednesday, fingers crossed.

Can you let me know how you get on...I'm looking for a good auto electric sort in Northants....Thanks

 

[GregE240]

Where in Northants Ian?

I'm off J18 of the M1, got one or two for you, if that helps?

You can PM if you don't want to be more specific

 

[IanA2]

Where in Northants Ian?

I'm off J18 of the M1, got one or two for you, if that helps?

You can PM if you don't want to be more specific

Anywhere really, I'm nearby Oundle.

Thanks

 

[GregE240]

Hmm......okay.

Well, I use 2 different indies. One based in Coventry, the other in Milton Keynes.

The Mk one is Auto Class: http://www.auto-class.co.uk/

Run by 2 ex MB MK blokes, James and Pete. Both extremely knowledgeable, and they know SLs very well indeed.

I had the E Class serviced by them, and take the SL there for work too.

HTH,
Greg