SOS, SRS issue after horn wouldn’t turn off
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2004 E500
SOS, SRS issue after horn wouldn’t turn off
Sorry if this has already been discussed - but I was unable to find if it was 😬.
I have recently been having issues with my 2004 E500. It seemed to stem from an issue with the horn which stopped working with the car running but came on and stayed on after the ignition was turned off. I removed the fuse as a temp fix and tried to see if there was a wiring issue visible. Unable to find an issue (quick check) I refit fuse and disconnected the horns. This left the horn relay powered up after key was removed and battery died overnight. Since this - the SOS & SRS warnings have been coming on intermittently. Now they seem to be staying on and I’m getting a “turn lights off” message when I remove the key even though lights are off. I’m assuming somewhere down the line they are related (bad earth, faulty connection, low voltage somewhere) but would like a place to start if anyone knows a common denominator with these issues. I do have icarsoft which gives a 902f DTC that won’t clear but nothing on instrument or steering wheel. I was a master technician in my younger days but not on MB so have the skill set and empty wallet enough to get deep if needed. If necessary I will take it to a STAR equipped workshop - but would prefer to exhaust all inexpensive options first. Thanks in advance, Brian (North County San Diego, California if anyone’s local with STAR)
I have recently been having issues with my 2004 E500. It seemed to stem from an issue with the horn which stopped working with the car running but came on and stayed on after the ignition was turned off. I removed the fuse as a temp fix and tried to see if there was a wiring issue visible. Unable to find an issue (quick check) I refit fuse and disconnected the horns. This left the horn relay powered up after key was removed and battery died overnight. Since this - the SOS & SRS warnings have been coming on intermittently. Now they seem to be staying on and I’m getting a “turn lights off” message when I remove the key even though lights are off. I’m assuming somewhere down the line they are related (bad earth, faulty connection, low voltage somewhere) but would like a place to start if anyone knows a common denominator with these issues. I do have icarsoft which gives a 902f DTC that won’t clear but nothing on instrument or steering wheel. I was a master technician in my younger days but not on MB so have the skill set and empty wallet enough to get deep if needed. If necessary I will take it to a STAR equipped workshop - but would prefer to exhaust all inexpensive options first. Thanks in advance, Brian (North County San Diego, California if anyone’s local with STAR)
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