GM Tech II will read it for sure. Maybe also a good Snap-On reader. Could be a wire issue with the harness, or a bad hub. On my 00 GPGT it did this for a while and eventually the lights stayed on 24/7. Turned out to be a wire issue inside the harness. Replaced the harness and all is well. Not sure if the 02's have the separate harness from the hub to the main loom or not like the 00.