Service Engine Light On Start-up Problem

[spikefish]

Last week I took my 2000 Sierra in for the annual safety inspection. The technician informed me that the service engine light did not come on when the ignition is turned on, but before starting, as required in my state. After several cycles the light came on, and continued to function properly afterwards--I passed the inspection.

 

Now, the light is intermittent when turning the ignition on---any ideas?