Good morning to all. While driving yesterday I noticed that my check engine light came on for about a minute then went off and has not come back on. I have noticed this in the past a couple of times as well. The truck is running great with no issues. How do I check for codes? Thanks in advance for any guidance.

 

If the light turns off, that means that the ecm corrected the issue on its own. And you might be able to pull the code with the light off, but most likely not.
If you dont have a code scanner, you can check codes with a paper clip by crossing the pin on the top right, and then second from the left on the bottom of the obd port.(If you are looking at it with the smaller part facing up). And then you count the times that the check engine light flashes to get the code number.

 

continuous vs KOER vs KOEO codes, some codes only while running, some key on, and some will no matter what(light go off, i think)

 

Thank you Shagg. So there is a connection to have the local auto parts store check for codes?! I was figuring that the light came on due to me not down shifting/up shifting when recommended by the manual. I drive my truck around town in third gear most of the time between 30 and 40 MPH at just under 2000 RPM on slightly hilly roads.

 

If you have a stick shift and were lugging the motor, engine light could have come on for a blip, sure.

You would really need to be lugging though, to the point of nearly stalling it out.

Or you were bouncing off the speed limiter at high RPM which may trigger it too. Sounds more like you are lugging your motor though.

 

Click this & read the whole caption carefully (a few times, if necessary):

(phone app link)
No, the EEC can't correct any problems. Ever. None.