GMC specific DTC OBD2 code: P1642 FC Relay 2 And 3 Control Circuit
GMC specific DTC OBD2 code: P1643 Engine Speed Output Circuit
GMC specific DTC OBD2 code: P1645 EVAP Solenoid Output Circuit
GMC specific DTC OBD2 code: P1646 Driver 1 Line 6
GMC specific DTC OBD2 code: P1647 Driver 1 Line 7
GMC specific DTC OBD2 code: P1650 Driver 2-Input High Voltage
GMC specific DTC OBD2 code: P1651 Fan 1 Relay Control Circuit
GMC specific DTC OBD2 code: P1653 Oil Level Lamp Control Circuit
GMC specific DTC OBD2 code: P1654 Service Throttle Soon Lamp Control Circuit
GMC specific DTC OBD2 code: P1655 EVAP Purge Solenoid Control Circuit