I have a starting issue with my 2001 C5. The battery is good and the
starter has been replaced. When I turn the key to start, there has been
a few seconds delay until the starter kicks over. I think this is to
allow time to check and cut off lights etc to give max cranking amps
to the starter. Last night I moved the key to start and after a few
seconds the light went out and the amp meter (on the dash) dropped
back but the starter never kicked over. I am starting to suspect a
computer module is screwing up. I was about to call for the wrecker
this morning and it is now starting.

How do you reset the computer that controls the starting sequence?

Are that codes that may show something?