Computer reset 1994 GMC pickup.

Hey RICK D P,

Just remove the negative battery cable for 1 minute and the codes are cleared.

Here is a great guide on how to clear the codes and how to gather them as well.

https://www.2carpros.com/articles/buick-cadillac-chevy-gmc-oldsmobile-pontiac-gm-1983-1995-obd1-code-definitions-and-retrieval-method

Please let us know happens so it will help others.

Best, Ken