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Fuse Usage
TRL TRN Trailer Left Turn
TRR TRN Trailer Right Turn
TRL B/U Trailer Back Up Lamps
VEH B/U Vehicle Back Up Lamps
HDLP PWR Headlamp PowerFuse Usage
RT TURN Right Turn Signal Front
LT TURN Left Turn Signal Front
HDLP W/W Not Used
LT TRN Left Turn Signal Rear
RT TRN Right Turn Signal Rear
RR PRK Right Rear Parking Lamps
TRL PRK Trailer Park Lamps
LTHDLP Left Headlamp
RTHDLP Right Headlamp
FRPRK Front Parking Lamps
INT BAT Instrument Panel Fuse Block Feed
ENG I Engine Sensors/Solenoids, MAF,
CAM, PURGE, VENT
ECM B Engine Control Module, Fuel Pump
Module, Oil Pressure
ABS Anti-Lock Brake System
ECM I Engine Control Module Injectors
F/PUMP Fuel Pump
DRL Daytime Running Lamps
A/C Air Conditioning
HORN Horn
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2003 - Sonoma OM
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Fuse Usage
W/W PMP Not Used
HORN Horn
BTSI Automatic Transmission Shift Lock
Control System
B/U LP Back Up Lamps
IGN B Column Feed,Ignition 2, 3, 4
STARTER Starter
RAP Retained Accessory Power
LD LEV Not Used
OXYSEN Oxygen Sensor
IGN E Engine
MIR/LKS Mirrors, Door Locks
FOG LP Fog Lamps
IGN A Starting and Charging Ignition 1
STUD #2 Accessory Feeds, Electric Brake
PARKLP Parking Lamps
LR PRK Left Rear Parking Lamps
LIFTGLASS Liftglass
IGN C Starter Solenoid, Fuel Pump,
PRNDL
HTDSEAT Heated SeatFuse Usage
HVAC Heating,Ventilation, Air Cooling
System
TRCHMSL Trailer Center High Mount Stop Light
RRDFOG Rear Defogger
TBC Truck Body Computer
CRANK Clutch Switch, NSBU Switch
CHMSL Center High Mounted Stoplamp
HAZLP Hazard Lamps
VECHMSL Vehicle Center High-Mounted
Stop Lamp
RR DEFOG Rear Defogger
HTDMIR Heated Mirror
ATC Transfer Case (Four-Wheel Drive)
STOPLP Stop Lamps
RR W/W Rear Window Wiper
5-93
2003 - Sonoma OM
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Headlamps (cont.)
Halogen Bulbs............................................5-50
One-Piece Front Turn Signal Lamps...............5-52
Two-Piece Front Turn Signal Lamps...............5-53
Heated Seats................................................... 1-5
Heating.........................................................3-18
Highway Hypnosis...........................................4-34
Hill and Mountain Roads..................................4-34
Hitches..........................................................4-56
Hood
Checking Things Under.................................. 5-8
Release....................................................... 5-9
Horn ............................................................... 3-4
How to Add Coolant to the Coolant
Recovery Tank............................................5-32
How to Add Coolant to the Radiator..................5-34
How to Add Fluid....................................5-22, 5-24
How to Check................................5-20, 5-23, 5-59
How to Check and Add Fluid
............................5-25
How to Check Lubricant
..........................5-47, 5-49
How to Check Power Steering Fluid
..................5-37
How to Inspect the Engine Air Cleaner/Filter
.......5-19
How to Use This Manual
...................................... ii
How to Wear Safety Belts Properly
...................1-15
Hydraulic Clutch
.............................................5-24
Hydraulic Clutch System Check
........................6-27
Hydroplaning
..................................................4-30I
If No Steam Is Coming From Your Engine..........5-29
If Steam Is Coming From Your Engine...............5-28
If the Light Is Flashing.....................................3-30
If the Light Is On Steady.................................3-31
If You Are Stuck in Sand, Mud, Ice or Snow.......4-40
If You Do Decide To Pull A Trailer.....................4-52
If You’re Caught in a Blizzard...........................4-38
Ignition Positions.............................................2-20
Ignition Transmission Lock Check......................6-29
Infants and Young Children, Restraints...............1-32
Inflation–Tire Pressure...................................5-58
Inspection
Brake System.............................................6-32
Engine Cooling System................................6-31
Exhaust System..........................................6-31
Fuel System...............................................6-31
Part C - Periodic Maintenance.......................6-31
Steering, Suspension and Front Drive
Axle Boot and Seal..................................6-31
Throttle System...........................................6-32
Transfer Case and Front Axle
(Four-Wheel Drive)...................................6-32
Installing a Garage Door Opener.......................2-43
Instrument Panel
Cluster.......................................................3-21
Overview..................................................... 3-2
7
2003 - Sonoma OM