One problem related to warning light on has been reported for the 2002 GMC Envoy. The most recently reported issues are listed below.
Defective air bag module # p/n 15080860 serv/no 122162269 aj7: for several years a airbag warning light displayed on my GMC Envoy. I took it to several different repair places and all felt it was probably a defective module which should be a recall issue. Onstar said dealer needed to do more diagnostics. Dealer did not perform when first taken in for such. With recent news of deaths due to ignition and airbag failures I became suspicious. Finally, returned to dealers and insisted a comprehensive diagnostic on airbag module be done. . . Couple of days servicing. Module finally confirmed defective. They replaced with #12233969 (module 16712-CT). Cost total for defective part and servicing was $746. 28. Firmly believe this should have been a safety recall issue all along, but dealer said gm did not declare as such. Other service repair technicians disagreed. Fortunately no accident was involved in the several years this was an issue.