So yesterday i was driving and out of nowhere my car started to jerk then went into limp mode with the check engine light on. When the people at autozone hooked it up to the computer it put out the error code P0715-input turbine speed sensor circuit malfunction. The guy at autozone said it was probably the secondary air pump, and NOT to go to the dealership. However, when I talked to the people at mercedes, they said this error code can mean many different things and they want $250 just to diagnose the problem. Has anyone had any experience with this? I really dont want to bring it to the dealer if I dont have to. BTW this is a 2006 e350 4matic.

 

Most times the dealer will wave the diagnose charge if you get it fixed there.
I went for a leak , I had just had the transmission serviced at the dealer.
When they checked it out it was a electric plug for the trans it was only $30 or $40 more than the diagnose charge to fix it so I just let them.
Cost was around $160.

If you don't have a good Ind shop around the dealer maybe your best bet as they for the most part will not just put parts on untill it works and charge you.