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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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ApplicationCapacities
English Metric
Automatic Transmission
Drain and Refill5.0 quarts 4.7 L
Differential Fluid
Rear Axle
Front Axle4.0 pints
2.6 pints1.9 L
1.2 L
Air Conditioning Capacity
Air Conditioning Refrigerant R134a1.8 lbs 0.79 kg
All capacities are approximate. After refill, the levelmustbe checked.
All capacities are approximate. When adding, be sure tofill to the appropriate level or as recommended in
this manual. SeePart E: Maintenance Record on page 6-35
Capacities and Speci cations
Type VIN Code Transmission Spark Plug Gap Firing Order
2200
L4HAutomatic
Manual0.040 inches
(1.01 mm)1-3-4-2
4300
V6XAutomatic
Manual0.060 inches
(1.52 mm)1-6-5-4-3-2
5-95
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Normal Maintenance Replacement Parts
Part Number
Oil Filter*PF47
Air Cleaner Filter*A1163C
PCV Valve
2200 Engine
4300 EngineN/A
*CV7696
Automatic Transmission Filter Kit **24200796
Spark Plugs*41-948
Fuel Filter*GF481
Windshield Wiper Blades
Length
Type20 inches (51 cm)
Trico
*ACDelco
®Part No.
**GM Part No.
5-96
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Selecting the Right Schedule
First you’ll need to decide which of the two schedules is
right for your vehicle. Here’s how to decide which
schedule to follow:
Short Trip/City Definition
Follow the Short Trip/City Scheduled Maintenance if any
one of these conditions is true for your vehicle:
•Most trips are less than 5 miles (8 km). This is
particularly important when outside temperatures
are below freezing.
•Most trips include extensive idling (such as frequent
driving in stop-and-go traffic).
•You frequently tow a trailer.
If the vehicle is used for delivery service, police,
taxi or other commercial application.
One of the reasons you should follow this schedule if
you operate your vehicle under any of these conditions
is that these conditions cause engine oil to break
down sooner.
Short Trip/City Intervals
Every 3,000 Miles (5 000 km):Engine Oil and Filter
Change (or 3 months, whichever occursfirst). Chassis
Lubrication (or 3 months, whichever occursfirst).
Drive Axle Service.
Every 6,000 Miles (10 000 km):Tire Rotation.
Every 15,000 Miles (25 000 km):Engine Air Cleaner
Filter Inspection. Front Wheel Bearing Repack
(two-wheel drive only) (or at each brake relining,
whichever occursfirst). Automatic Transmission Service
(severe conditions only).
Every 30,000 Miles (50 000 km):Engine Air
Cleaner Filter Replacement. Fuel Filter Replacement
(4.3L V6 engine only).
Every 50,000 Miles (83 000 km):Automatic
Transmission Service (normal conditions).
Every 90,000 Miles (150 000 km):Fuel Filter
Replacement (2200 L4 engine only).
Every 100,000 Miles (166 000 km):Spark Plug Wire
Inspection. Spark Plug Replacement. 4.3L V6 Engine
Only: Positive Crankcase Ventilation (PCV) Valve
Inspection.
6-5
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Every 150 000 Miles (240 000 km):Cooling System
Service (or every 60 months, whichever occurs
first). Engine Accessory Drive Belt Inspection.
These intervals only summarize maintenance services.
Be sure to follow the complete scheduled maintenance
on the following pages.
Long Trip/Highway Definition
Follow this scheduled maintenanceonlyif none of the
conditions from the Short Trip/City Scheduled
Maintenance are true. Do not use this schedule if the
vehicle is used for trailer towing, driven in a dusty area
or used off paved roads. Use the Short Trip/City
schedule for these conditions
Driving a vehicle with a fully warmed engine under
highway conditions will cause engine oil to break down
slower.
Long Trip/Highway Intervals
Every 7,500 Miles (12 500 km):Engine Oil and Filter
Change (or every 12 months, whichever occurs
first). Chassis Lubrication (or 12 months, whichever
occursfirst). Drive Axle Service. Tire Rotation.
Every 15,000 Miles (25 000 km):Engine Air Cleaner
Filter Inspection. Automatic Transmission Service
(severe conditions only).Every 30,000 Miles (50 000 km):Fuel Filter
Replacement (4.3L V6 engine only). Engine Air Cleaner
Filter Replacement. Front Wheel Bearing Repack
(two-wheel drive only) (or at each brake relining,
whichever occursfirst).
Every 50,000 Miles (83 000 km):Automatic
Transmission Service (normal conditions).
Every 90,000 Miles (150 000 km):Fuel Filter
Replacement (2200 L4 engine only).
Every 100,000 Miles (166 000 km):Spark Plug Wire
Inspection. Spark Plug Replacement. 4.3L V6 Engine
Only: Positive Crankcase Ventilation (PCV) Valve
Inspection.
Every 150,000 Miles (240 000 km):Cooling System
Service (or every 60 months, whichever occurs
first). Engine Accessory Drive Belt Inspection.
These intervals only summarize maintenance services.
Be sure to follow the complete scheduled maintenance
on the following pages.
6-6
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