n_caj

Hi all-- I've been experiencing a couple of issues with my 2009 E-class, just needed some help diagnosing.

After a few minutes of driving, my traction control light will turn on and an "ESP inoperable, see user manual" message pops up in the cluster. Through my own fiddling, if I hit the cruise control stalk after this message, the cruise control then becomes inoperable (fml).

Another issue I've been having is sometimes when I put the car in park after driving, the car will begin to idle high-- this is less frequent and has only happened maybe three times in the last month and a half.
Any help would be greatly appreciated, thank you!

cetialpha5

You need to get a scanner that can read MB specific codes. A cheap one will be an Autel AP200, under $50 on Amazon. There are many possibilities that can cause an ESP error. Once that kicks on, the cruise control is also inoperable so that's normal. The most likely cause is a bad brake light switch. But it could be the steering angle sensor, one of the wheel speed sensors or the magnetic ring, or yaw sensor, etc. You need the scanner to tell you what the actual problem is in order to be able to fix it. If you want to be cheap, you could just replace the brake light switch, that would cost less than the scanner and if that doesn't fix it, get the scanner, the other causes will be more than the scanner. Idling high isn't really an issue if you don't have any codes.