Every Chevrolet truck has an engine control module that manages the electronic components of the engine and monitors sensors for errors. Returning the ECM to its factory state may be necessary to troubleshoot or resolve a number of problems.
Remove the nut from the negative battery cable using a socket set or wrench. Slide the cable off of the battery and set it aside.
Turn the headlight switch to the “On” position to drain the ECM of any remaining power. Wait at least 10 minutes, then turn it back to the “Off” position.