1994 Buick Regal Check Engine and Coolant Warning Lights Stay On - OBD1 Diagnosis Help

I'm trying to pass a smog inspection on my 1994 Buick Regal, but both the Check Engine and Low Coolant warning lights remain illuminated. I've already disconnected the battery to reset the system, though I didn't turn on the headlight switch as suggested in some forums—this vehicle doesn’t have an OBD2 system. I recently purchased a GM OBD1 scanner from eBay, but it appears not to support my 1994 Buick Regal model. Can anyone provide guidance on how to diagnose or interpret these codes? Any advice would be greatly appreciated. Thanks, Gerald.