SL/R129: No dash lights, won’t start
Thread Starter
Newbie
Joined: Apr 2019
Posts: 12
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500SL
No dash lights, won’t start
Need some starting help. 1991 sl500 won’t start when dash lights aren’t present. When I turn the key forward, if I have dash lights, it starts fine. If no dash lights, it cranks and cranks but won’t kick over. I was thinking fuel pump relay? It sometimes runs rough at idle which I’ve read is also a symptom of fuel pump relay. I’ve read conflicting info on location of the relay. It’s a 119.155 engine.
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Joined: Mar 2016
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From: SF Bay Area, CA
190E 2.6L 1989, 190E 2.6L 1988, BMW 535dXdrive 2014, BMW 428i 2015
Sounds like you have some ignition switch issues. Rough idle is probably unrelated and not a fuel pump relay issue. Rough idle can have many culprits, fuel pump relay must be at the bottom of that list as I have never seen that come up for a rough idle.
Thread Starter
Newbie
Joined: Apr 2019
Posts: 12
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500SL
Yes. It was in fact the ignition switch. I replaced it myself. There are a couple of good videos out there I used as guidance. I consider myself as “moderately” inclined mechanically and it wasn’t a real hard job, I think I spent maybe an hour on it.
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Joined: Aug 2019
Posts: 28
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From: South Carolina
1999 SL500 Sport w/Pano, 2007 Jaguar XKR, 2009 Jaguar XJ Super V8 Portfolo
Need some starting help. 1991 sl500 won’t start when dash lights aren’t present. When I turn the key forward, if I have dash lights, it starts fine. If no dash lights, it cranks and cranks but won’t kick over. I was thinking fuel pump relay? It sometimes runs rough at idle which I’ve read is also a symptom of fuel pump relay. I’ve read conflicting info on location of the relay. It’s a 119.155 engine.
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Thread Starter
Newbie
Joined: Apr 2019
Posts: 12
Likes: 1
500SL
I’ve determined it’s a fuel issue. When I take it out of storage in the spring, I experience the occasional rougher idle on the old gas (even though I add StaBil before storage). Once I burn off that tank and refill with fresh gas, it pretty much disappears.
MBWorld Fanatic!
Joined: Mar 2016
Posts: 1,369
Likes: 195
From: SF Bay Area, CA
190E 2.6L 1989, 190E 2.6L 1988, BMW 535dXdrive 2014, BMW 428i 2015
Yes, I am the original owner of my '89 W201. Also have the '88. Both cars like to be used a few times a month. The more you use them to better they run.
Sitting for months on end was never good for my W201.
- Cheers!
Sitting for months on end was never good for my W201.
- Cheers!
