GM Service Manual Online
For 1990-2009 cars only

Park/Side Marker and Tail Lamps

The park/side marker and tail lamps are split between the following 4 fuses:

    • The FR PRK
    • The LR PRK
    • The RR PRK
    • The TRL PRK

These fuses receive voltage from the park lamp relay. When the headlamp and panel dimmer switch is in the auto position, the body control module (BCM) controls the relay by grounding CKT 1080 based on the input of the ambient light sensor. The park LPS fuse supplies battery positive voltage (B+) to the relay at all times.

When the headlamp and panel dimmer switch is in the PARK position, the relay is by passed through the INT PRK fuse. Current flows from the PARK LPS fuse through the headlamp and panel dimmer switch to the INT PRK fuse in order to feed the following fuses:

    • The FR PRK
    • The LR PRK
    • The RR PRK
    • The TRL PRK

Stop Lamps

The STOP LPS fuse supplies battery positive voltage (B+) at all times to the stoplamp switch. When the brake pedal is depressed, CKT 17 supplies battery positive voltage (B+) to the VEH STOP and the CHMSL fuses causing the lamps to light through CKT1320 and CKT 1620.

Turn Signal lamps

When the ignition switch is in the run position and the turn/hazard switch is in a turn position, voltage is supplied from the TURN fuse through the turn/hazard switch to the turn/hazard flasher, CKT 1696. The flasher then passes current back to the turn/hazard switch in an intermittent on and off pattern, CKT 1697. From the turn/hazard switch, voltage is supplied to the LT TURN or the RT TURN fuse, CKT 14 or CKT 15. From the fuse voltage is supplied to the respective lamps on CKT 2114 left or CKT 2115 right.

Hazard Lamps

When the turn/hazard switch is in the hazard position, voltage is supplied from the HAZ LP fuse at all times through the turn/hazard switch to the turn/hazard flasher, CKT 1508. The flasher then passes current back to the turn/hazard switch in an intermittent on off pattern, CKT 1697. From the turn/hazard switch, voltage is supplied to the LT TURN and the RT TURN fuse, CKT 14 or CKT 15. From the fuse, voltage is supplied to the respective lamps on CKT 2114 left and CKT 2115 right.