What is your question?
The check engine light was not initially coming on at all when in Self test mode with the key in the ignition preventing me from getting a smog. I ran the diagnostic on the truck and it came out with P0650 code for the "Malfunction indicator control circuit."
1st: the truck runs great and only has around 68,000 miles on it. I popped off the dash and removed the entire unit and tested the bulbs to see if that would solve the issue simply, but all the bulbs tested positive for connection.
2nd: Took the truck to shop to have some wiring redone specific to the indicator lights for the dash as some were chewed by mice due to sitting.
3rd: The light came on but very DIM after I got the wiring done at the shop, but now it wont go off at all when the car has is in self test and/or running.
4: I have not quite gone the 70 or so miles yet but the light still has yet to turn off with no noticeable driving issues. (I took out the seat warmer fuse) not issue tho.
5: thinking it is CPU? thoughts?
How long has your 2002 GMC Sonoma had this problem?
June 2019
Thank you for the response; the mice are killing me here! Probably going to have to replace the entire set of wires for instrument cluster.