Is there any way to display ECU error codes on the MID and / or resetting the check engine light. My light came on after running hard at 4000 RPM. I understand that there is some ECU update but have little time to get this to the dealer right away. My 300M had a way by turning the ignition on and off 4 times in a row to display the error codes and reset the light. Any help?

 

If it's really the engine issue, what are you going to do?

Check with your dealer. Without the OBD-II like device, you have no way to access error codes. And, IMO, 04TL cannot allow you to reset any MIL (check engine light) info.

I bet you have tried on/off 4 times, any good luck so far?

 

To reset, on many cars simply disconnecting the battery for a couple minutes will reset the ecu. You may also lose other things that will need to be reset, driver memory, radio presets....

For displaying the codes, someone with a service manuel may be able to help. I know on my VW a certain number of clicks on the MID selector would bring up the code.

 

If you disconnect the battery you will need the reset code for the stereo and the NAVI. You will also lose all you MPG, hours driven, trip miles, etc. I had this happen to me, light coming on after running hard in SS with little miles on the car. Took it in and they reset the ECU as they did not have the update yet. Happened again. Took it back and they said they had the update now and did so. to the ECU. Funny thing was, on the service order it said "replace air-fuel sensor". This was about 2-3 months ago. Never happened since.