Intermittent issue of transmission not shifting into gear

2008 MERCEDES BENZ S550
152,000 MILES • V8 • 4WD • AUTOMATIC
Avatar
ROOSEVELT FOREHAND
  • MEMBER
  • 1 POST
my car sometimes won't go into gear and i have to cut it off then try again until it does. why is that?
Jul 18, 2021 at 2:30 PM
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.
Advertisement
Avatar
SQM
  • AUTOMOTIVE REPAIR CONTRIBUTOR
  • 6,383 POSTS
Hello,

It sounds like a fault with the transmission control module (TCM) or the ISM (intelligence servo module). Does this happen when the engine is hot or cold or both?
What error codes are you getting with this?

https://www.2carpros.com/trouble_codes/obd2

With code read it will point us to the right direction.
So first step would be to get the car scanned for codes. If it is the ISM, it does need to be programmed after install.

Let me know if you have any questions.
Thank you.

Jul 18, 2021 at 3:02 PM
Advertisement