GMC 2003 C4C042 Owner's Manual page 335

Fuse Usage
-
RH PARK LP Right
-
LH PARK LP Left hand Parking Lamps
RADIO U Radio
PWR WINDOW Power Windows
BRAKE ISO Brake Warning Lamp
SPARE Spare Fuse
-
L RR TRUCK Left Rear Trailer Wiring
SPARE Spare Fuse
SPARE Spare Fuse
SPARE Spare Fuse
-
R RR TRUCK Right Rear Trailer Wiring
SPARE Spare Fuse
hand Parking Lamps
Relay Usage
BRAKE LAMP C4/C5 Brake Lamps, C6/C7/C8
Tractor/Trailer Wiring
IGN 4 Ignition
MARKER LP Sidemarker and Clearance Lamps
HTD FUEL LB7/LG4 Heated Fuel
AIR HTR LG4 Air Heater
ECU LG4 Electronic Control Unit
MAINTAIN
DRL Daytime Running Lamps
CHMSL ISO Center High Mounted Stop Lamp
HTD MIRR Heated Mirrors
-
R TRN TLR Right Trailer Turn Signal
-
L TRN TLR Left Trailer Turn Signal
SPARE Spare Relay
SPARE Spare Relay
SPARE Spare Relay
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