Have Mercedes Questions? Ask a Mechanic for Answers ASAP
Hello, my name is Bobby. Thanks for the question. Can you tell me if the check engine light is coming on when this occurs?
Thank you. Most of the time this is a problem with a vehicle speed sensor. If it stops reading then the computer has no way of knowing how to calculate things like shift points. Since the check engine light is on the computer needs to be scanned for codes to see what problem it is identifying. Most auto parts stores will scan the computer for free and give you the codes. This is of course if you plan on fixing it yourself. If not then you should start by having a shop scan it, but this is the most likely cause.