Mercedes B Class 2008: Symptoms of a possible defective crankshaft sensor

Hello, I had similar signs with my 2011 Mercedes E-Class. You are probably right with your assumption. It turned out that it was actually the wiring harness/connector of the crankshaft sensor. The symptoms you describe, such as the indicator light, uneven engine running and starting difficulties, were also present in my car before the repair. This is definitely not a minor problem. The crankshaft sensor plays a crucial role in the engine, providing important data on ignition timing and fuel injection. If this sensor fails, it can lead to significant engine problems, as you are experiencing. After replacing the crankshaft sensor and its wiring, my Benz ran smoothly again. So it was a serious but fixable issue. I hope this helps you and wish you that your Mercedes will soon be fit again!

(Translated from German)

Hi, thanks for the quick reply! Your experience sounds pretty similar to what I'm going through right now. Good to know that it seems to have been fixed for you after replacing the sensor and wiring. Do you happen to remember how much all that fun cost you? And has anything else come up on your Mercedes since then that could be related to the original problem?

(Translated from German)

Hey, sure, no problem! After the mechanic had repaired the crankshaft sensor and the wiring harness/plug, my Benz was running like a kitten again. It cost me €170, which I thought was absolutely fair for this type of repair. And no, nothing has come up since then that could be related to the original problem. So don't worry, if that's the case for you too, you can probably drive with peace of mind afterwards!

(Translated from German)

Ah, thanks for the info! 170 actually sounds pretty fair for such an important repair. Your experience has definitely helped me understand the situation better. I'll take my B-Class to the garage as soon as possible. Hopefully it's just the crankshaft sensor. Having a smooth running car again would be a blessing. Thanks again for your help!

(Translated from German)

Hello, I have error message P0339 on my Mercedes S205 automatic. At first I had misfiring when accelerating and changing gear. I then replaced the crankshaft sensor (Hitachi), after which all the problems were gone, but the error message could not be deleted. After a few weeks, the problems reappeared. So today I fitted a new sensor, this time an original one from Mercedes. The car runs again without any problems, but the error cannot be deleted again. what else can I do? the plug looked good so far, no corroded contacts or similar. Kind regards

(Translated from German)

Check the wiring harness leading to the crankshaft sensor for any signs of damage or wear, as a faulty connection could cause the error code to persist. Ensure all connections are secure and free of corrosion. If the issue continues, consider having the ECU checked for faults, as it might need a reset or update. Let me know how it goes or if you have further questions!