Slap 22

1997 gcv no ck engine light key on all other message ctn lights work. Is the pcm the controller of self diagnostic sequence? If so any sugesstion as to how to correct the problem.

Thanks for any advise

 

Welcome to DF
Are you saying the ck engine lite does not come when you turn the key on? If the lite is not coming on,you could have a bulb thats out.

 

Thanks for the reply, I don't think it's a bulb the cel comes on when a code sets. It is my opinion that the PCM is not doing a self diagnostic test.
Slap22, 09/12/2010

 

Why do you think that.

 

My thinking is there is power to the circuit, the PCM either complete the circuit by grounding or furnish instruction to complete the circuit. Which initiate the bulb check and various monitored emission system.
Any advise is appreciated.

08/12/2010
Slap22

 

So you turn the key on and the check engine light doesn't light up? Is that your concern?

 

Yes Tizzy 1, that is the problem. If the CEL do not come for 3 seconds that is a failure on smog check.

08/13/2010
Slap22

 

Tizzy1
CEL when I ground terminal 22 the cel light come on with key in start position. My question is, does the PCM ground CEL? Or is the grounding part of the self diagnostic.

08/15/2010
Slap22