Check engine and brake lights are on and keeps going into Limp mode

JONATHANTRIPP

MEMBER
2004 MERCEDES BENZ E320
AUTOMATIC
192,000 MILES

I have a check engine light, a brake light in the center when it says malfunctioning brake. Cut car off any car keeps going into limp mode. I put it on my scanner and my scanner won't pick up anything; it won't send me a cod.E

Sunday, April 18th, 2021 AT 2:02 PM

1 Reply

JACOBANDNICKOLAS

MECHANIC
109,885 POSTS

Hi,

If you have a scanner that only reads powertrain codes, that is likely why it isn't finding anything. What you need to do is scan the can-bus system. CAN stands for controller area network. Basically, all the modules/computers are tied together via a few wires. By scanning the entire system using a scanner capable, it will identify any codes stored in any of the modules. Here is a video showing how it is done:

https://youtu.be/InIlnsjOVFA

Try having that done. Chances are it is related to an ABS/wheel speed sensor, but it needs to be scanned to determine it and which one.

Let me know what you find or if you have other questions.

Take care,

Joe