1992 Mercedes-Benz 300SE Q&A
1992 Mercedes-Benz 300SE Question: Left turn signal remains lit even after turning engine off.
The left side turn signal lights (front and rear) remain fully lit during operation of the car (without activating the signal lever) and remain on even after the engine has been turned off. This, obviously, results in the battery being drained to zero charge if not used and recharged every day or so. Is this a problem in the ignition switch or, as has been suggested to me, in a combination relay? Would a junkyard be a good place to try or is buying used electrical equipment there a bad idea? (I'm assuming that the dealer price for a new part may be prohibitive or not cost-effective for such an old car). Thanks in advance. - Visitor
To properly diagnose your turn signal issue correctly, the circuit would need to be tested to find the faulty component. As far as using used parts. The chance of the part being functional is less than 100%. So without a diagnoses you replace a part and it doesn't fix the problem you don't know if that part you installed is faulty or if you replace the wrong part.So you, either one, take the part back and exchange it for one that work or you replace another part and see if it fixes the problem. I know cost plays an important role in auto repair. Most of the time it is most cost effective to have the problem properly diagnosed and repaired right the first time as to throw used parts at it not knowing if the part is faulty or if you replade the wrong part. - Visitor
I'm was experiencing the same problem and I replaced the head light switch on the interior dash. It consisted of a wiring harness that can be accessed by popping out the switch with a screw driver. The wiring harness cost me $80 and the problem was solved - STL Finest