SL/R230: Plz Help - 2008 SL550 won’t crank... now no “Key On” Or windows....
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Joined: Feb 2009
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2005 E55 / 2001 e39 M5
Plz Help - 2008 SL550 won’t crank... now no “Key On” Or windows....
Thanks in advance- I’m about at my wits end on this one.
I took a deposit on it to sell the car when I was laid off back in May. They were on the way to pick it up and I was cleaning it up a bit when the check engine light came on. It was the code for the electric air/smog pump.
I pulled the relay, cleaned and replaced like I did a year ago when it had the same issue (which fixed it until now), and the car hasn’t started since.
The starter relay is behind the air pump relay on the passenger side under hood box, so I removed, cleaned and replaced it as well but no luck.
I tried a different fresh starter battery today, probed around a little, and now the driver side windows won’t roll up or down.
I’m leaning towards it being an ignition switch, but had a falling out with the friend with a SDS.
All head/tail lights work, horn and stereo work but the dash doesn’t activate when the key is turned to the “on” position and AC doesn’t power up.
Ive tried locking and unlocking - trunk opens and closes as it should.
Any specific fuses/relays or switches I can test without SDS?
I took a deposit on it to sell the car when I was laid off back in May. They were on the way to pick it up and I was cleaning it up a bit when the check engine light came on. It was the code for the electric air/smog pump.
I pulled the relay, cleaned and replaced like I did a year ago when it had the same issue (which fixed it until now), and the car hasn’t started since.
The starter relay is behind the air pump relay on the passenger side under hood box, so I removed, cleaned and replaced it as well but no luck.
I tried a different fresh starter battery today, probed around a little, and now the driver side windows won’t roll up or down.
I’m leaning towards it being an ignition switch, but had a falling out with the friend with a SDS.
All head/tail lights work, horn and stereo work but the dash doesn’t activate when the key is turned to the “on” position and AC doesn’t power up.
Ive tried locking and unlocking - trunk opens and closes as it should.
Any specific fuses/relays or switches I can test without SDS?
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Joined: Jan 2006
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From: Atlanta, unfortunately
'09 S600, (2) R129 300SLs, '03 SL500, '03 SL55
You could look through the electrical drawings (downloadable for free) and discern if every circuit fed by a given ignition switch position is dead, but that could be tedious.
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Joined: Aug 2010
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From: Rockport, TX
2007 S65 AMG-Sold, 2007 SL55 P030 - 2016 GL450 - - 2017 AMG GTS - Sold - 2015 AMG S65
Pinout
I have worked through some of these issues before.
Last edited by Hendrik Koster; Aug 3, 2020 at 07:14 AM.
Banned
Joined: Jan 2006
Posts: 1,982
Likes: 393
From: Atlanta, unfortunately
'09 S600, (2) R129 300SLs, '03 SL500, '03 SL55
Bypassing the switch seems like an excellent idea to me. You can use a paperclip to complete connections to the power circuits. Note that you won't be able to start the engine, however, since the signal to the engine controller to start the engine is passed from the ignition switch by way of a CAN message.
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2005 E55 / 2001 e39 M5
10-4, biggest concern for now is getting the windows to roll back up as the car has to live outside. I have it covered with a weatherproof cover for now but would love to get it sealed back up.
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Joined: Jan 2015
Posts: 389
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From: Seattle, WA
SL500
As far as getting the windows back up, Have you disconnected both batteries for 5 minutes and then reconnected? Then turn the ignition only to the accessories position, depress the windows button only part way?
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Thread Starter
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Joined: Feb 2009
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2005 E55 / 2001 e39 M5
thank you- I’ll try this tomorrow. I feel like my other cars had a remote option to open all windows if you hold the unlock on the fob but that didn’t seem to work either...
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