Is there a way to trigger a self diagnosis of the instrument cluster
of a 2004 GMC Pickup? I know with some Fords I can hold the odometer
reset when I turn the ignition switch to "run" and trigger a
instrument cluster self test. Is there anything like this for a GM
vehicle?

Ed

on 99 and up when you turn the key to the run position/it will do a sweep
and bulb test every time,other wise scan tool is required w/functional
test option/hope that helps