Rough Idle and CEL on

[SBG]

Yep. I found it last night. Feeling a little sheepish. What's interesting is that when pressing the button, there is no red LED showing codes, or when pressing longer, the codes are cleared. Next step is to check fuses and wiring. If there are any common problem spots, let me know.

 

[emerydc8]

The key has to be on (engine off) in order to power the LED/diagnostic module. Hold the button down for 3 seconds and let go, then count the flashes.

 

[SBG]

Tried it with key on. Nothing on either the DM or pin 19. Fuses are ok.

I assume CEL was triggered my the ambient air temp sensor not being connected. However that wouldn’t explain the lack of power to the DM. Ideas are welcome.

 

[gsxr]

If the CEL is stuck on and there is no normal response from pin #19... could be the DM itself has failed. Not sure how to test this without swapping in a replacement DM.

 

[SBG]

I’m going to trace the wiring down and see where the power stops and check connectors. It has enough power somewhere to light the CEL. Stay tuned.