SL/R230: Various random warning lights
Thread Starter
Newbie
Joined: Jul 2014
Posts: 13
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350 SL
Various random warning lights
2005 SL350 (UK) 79,000 miles
Hi. I've owned my SL350 for 20 years and apart from one or two minor issues it has been very reliable - up until now!
After about 5 minutes with the engine running the headlights give a quick flash resulting in a message on the dash. Also I get an occasional red battery warning which disappears after a couple of seconds and also other random warnings. I get one or two "malfunction memories" when turning the ignition off. All these warnings disappear when the ignition is turned off. The car starts and runs fine, the batteries are almost new.
The car is going in to a specialist in three weeks but any clues as to the problem would be a big help.
Thanks in advance.
Hi. I've owned my SL350 for 20 years and apart from one or two minor issues it has been very reliable - up until now!
After about 5 minutes with the engine running the headlights give a quick flash resulting in a message on the dash. Also I get an occasional red battery warning which disappears after a couple of seconds and also other random warnings. I get one or two "malfunction memories" when turning the ignition off. All these warnings disappear when the ignition is turned off. The car starts and runs fine, the batteries are almost new.
The car is going in to a specialist in three weeks but any clues as to the problem would be a big help.
Thanks in advance.
MBWorld Fanatic!
Joined: Aug 2020
Posts: 1,339
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From: Gretna, NE
'03 SL55 Black, '03 SL500's Aegean, Mars Red, Tazanite, Alabaster, '11 S550 Flint Gray
Many warnings in the cluster are the default and need to be turned off by the responsible module. For example, loss of communication with the SBC module will give you brake warnings. Brakes might be fine, but the cluster is not getting the OK message.
Senior Member
Joined: Apr 2007
Posts: 436
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Former R230, W220 and W221 owner
Member
Joined: Jan 2003
Posts: 185
Likes: 18
From: Cedar Park, Texas
2013 Porsche 911 Carrera 4S, 2004 SL55, 2012 Lexus IS250, 2021 Toyota Highlander
Make note of the other random warnings and see if they are tied to the same SAM as the headlight. Definitely get it scanned for codes. The red warning light could be a number of things. In my case, it was both the BCM and a voltage regulator. Good luck. Let us know what it turns out to be.
