Mysterious check engine

[X-North]

I just did around my town 5 to 10 kilometers and suddenly a Check engine lighted. After one kilometer i made a stop at my bank and stopped the truck. 5 minutes after that i restarted the truck and the check engine light was gone. Is it a CM code that was there but solved or is it a running code that went out because i restarted the truck ?

 

[MrShorty]

It will store a CM code to indicate what fault the computer saw. The CEL goes off if the fault goes away. KOER codes are only set during the KOER test.

 

[X-North]

Ok but is it stored again if the light never came back? I made a ride today and the light never reappered. For the KOER codes they are set during koer test but like it tell Running engine ...so it is supposed to be a check engine light too when the truck is running down the road ...no???

 

[MrShorty]

When the computer detects a fault, the light comes on and a code is stored in CM. If the fault goes away, the CEL goes off, but the code remains in CM. If the fault doesn't recur within ~80 drive cycles, the computer will clear the code from CM. If you've only driven a few times since the CEL came on, the code should still be in CM.

 

[X-North]

thank oyu