Fix the cause of the light coming on and the light will reset itself within a few drive cycles.
If a knock sensor was bad, the check engine light would be illuminated and the code(s) set would indicate so.
How do you reset check engine light for the 2009 Chevy trail blazer?
Check engine light. Should be able to take it to AutoZone and they'll put their reader to it to tell you what's going on with your engine.
These codes can be caused by aftermarket scan tools and also by unpluging the scan tool with out turning the key to the off possition.
You can either bring it in to a Chevy dealer or use a programmer/tuner to reset the check engine light.
First you must fix the problem that caused the light to be set. You can try to reset the light by disconnecting the negative battery cable for five minutes. If that does not work you will need an 0BD2 scanner in order to reset the light.
If the check engine light is blinking that means an engine cylinder misfire has been detected
Check
The check engine light (service engine soon) comes on and stays on when a problem is detected by the self diagnosis system of your vehicle.
It requires an engine scanner to do that.
No, only a problem that effects emissions will set the check engine light.