GM Service Manual Online
For 1990-2009 cars only
Figure 1:

Daytime Running Lamps (DRL) Control Module Power and Ground, Ambient Light Sensor


Object Number: 1426461  Size: FS
Master Electrical Component List
Exterior Lighting Systems Description and Operation
Control Module References
Turn Signal/Headlamp Switch
Power, AM 1, Door, Tail, P/Point, ECU-B, Stop, OBD, INV Fuses
Headlamps ON Indicator, Crank Signal, Vehicle Speed Signal
Power, AM 1, Door, Tail, P/Point, ECU-B, Stop, OBD, INV Fuses
Junction Block - Instrument Panel Right
S103, G103
SP201 and G201
Figure 2:

Turn Signal/Headlamp Switch


Object Number: 1426490  Size: FS
Master Electrical Component List
Exterior Lighting Systems Description and Operation
Control Module References
Headlamps
Daytime Running Lamp (DRL) Control Module Power and Ground, Ambient Light Sensor
Multifunction Alarm Module, Horn, Hazard, Turn Signal/Headlamp Switches
Junction Block Instrument Panel - Right
SP200 and G200
Figure 3:

Headlamps


Object Number: 1426499  Size: FS
Master Electrical Component List
Exterior Lighting Systems Description and Operation
Control Module References
Turn Signal/Headlamp Switch
Air Pump, ETCS, Head, Alt S, EFI, Hazard EFI 2 Fuses
S103, G103