Fuses Usage
6 Driver Side Low-Beam Headlamp
7 Windshield Wiper
8 Active Transfer Case
9 Windshield Washer
10 Powertrain Control Module B
11 Fog Lamps
12 Stoplamp
13 Cigarette Lighter
14 Ignition Coils
15Transmission Control Module
Canister
16 Truck Body Controller, Ignition 1
17 Crank
18 Airbag
19 Trailer Electric Brake
21 Horn
22 Ignition E
23 Electronic Throttle Control
24Instrument Panel Cluster,
Driver Information Center
25Brake Transmission Shift
Interlock
26 Engine 1
27 BackupFuses Usage
28 Engine Control Module 1
29 Engine Control Module
30 Air Conditioning
31 Injector A
32 Trailer
33 Antilock Brakes (ABS)
34 Ignition A
35 Blower
36 Ignition B
50 Passenger Side Trailer Turn
51 Driver Side Trailer Turn
52 Hazard Flashers
53 Transmission
54 Oxygen Sensor B
55 Oxygen Sensor A
56 Injector B
57 Headlamp Driver Module
58 Body Controller 1
59 Electric Adjustable Pedals
61Vehicle Stability Enhancement
System
62 Regulated Voltage Control
63 Air Solenoid
64 Air Pump
5-121
Relays Usage
37 Headlamp Wiper
38 Rear Window Wiper/Washer
39 Fog Lamps
40 Horn
41 Fuel Pump
42 Windshield Washer
43 High-Beam Headlamp
44 Air Conditioning
46 Headlamp Driver Module
47 Starter
49 Electric Adjustable Pedal
60 Powertrain
69 Air Solenoid
Miscellaneous Usage
48 Instrument Panel Battery
Rear Underseat Fuse Block
5-122
Fuses Usage
01 Passenger Door Control Module
02 Driver Door Control Module
03 Liftgate Module 2
04 Truck Body Controller 3
05 Rear Fog Lamps
06 Blank
07 Truck Body Controller 2
08 Power Seats
09 Rear Wiper
10 Driver Door Module
11 Ampli er
12 Passenger Door Module
13 Rear Climate Controls
14 Driver Side Rear Parking Lamps
15 Blank
16Vehicle Center High-Mounted
Stoplamp (CHMSL)
17Passenger Side Rear Parking
Lamps
18 Locks
19Liftgate Module/Driver Seat
Module
20 Blank
21 Lock
5-123
Fuses Usage
23 Blank
24 Unlock
25 Blank
26 Blank
27OnStar
®Overhead Battery,
OnStar®System
28 Sunroof
29 Not Used
30 Parking Lamps
31 Truck Body Controller Accessory
32 Truck Body Controller 5
33 Front Wipers
34 Vehicle Stop
35 Transmission Control Module
36Heat Ventilation Air
Conditioning B
37 Front Parking Lamps
Fuses Usage
38 Driver Side Turn Signal
39Heat Ventilation Air
Conditioning 1
40 Truck Body Controller 4
41 Radio
42 Trailer Park
43 Passenger Side Turn Signal
44 Heat Ventilation Air Conditioning
45 Rear Fog Lamps
46 Auxiliary Power 1
47 Ignition 0
48 Four-Wheel Drive
49 Blank
50 Truck Body Controller Ignition
51 Brakes
52 Truck Body Controller Run
5-124
(e)Make sure the safety belt reminder light and safety
belt assemblies are working properly. Look for any other
loose or damaged safety belt system parts. If you see
anything that might keep a safety belt system from doing
its job, have it repaired. Have any torn or frayed safety
belts replaced. Also see Checking the Restraint Systems
on page 1-70.
(f)Lubricate all key lock cylinders, hood latch assembly,
secondary latch, pivots, spring anchor, release pawl,
rear compartment hinges, outer liftgate handle pivot
points, rear door detent link, roller mechanism, liftgate
handle pivot points, latch bolt, fuel door hinge, cargo door
hinge, locks, and folding seat hardware. More frequent
lubrication may be required when exposed to a corrosive
environment. Applying silicone grease on weatherstrips
with a clean cloth will make them last longer, seal better,
and not stick or squeak.
(g)Inspect hoses for cracks, chafing, leaks, kinks, and
proper installation.
(h)Change automatic transmission fluid and filter if the
vehicle is mainly driven under one or more of these
conditions:
In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police, or delivery
service.(i)Drain, flush, and refill cooling system. This service can
be complex; you should have your dealer/retailer perform
this service. See Engine Coolant on page 5-29 for what to
use. Inspect hoses. Clean radiator, condenser, pressure
cap, and filler neck. Pressure test the cooling system and
pressure cap.
(j)A fluid loss in any vehicle system could indicate a
problem. Have the system inspected and repaired and
the fluid level checked. Add fluid if needed.
(k)If driving regularly under dusty conditions, inspect
the filter at each engine oil change.
(l)Visually inspect belt for fraying, excessive cracks, or
obvious damage. Replace belt if necessary.
Owner Checks and Services
These owner checks and services should be performed
at the intervals speci ed to help ensure vehicle safety,
dependability, and emission control performance. Your
dealer/retailer can assist with these checks and services.
Be sure any necessary repairs are completed at once.
Whenever any uids or lubricants are added to the
vehicle, make sure they are the proper ones, as shown
inRecommended Fluids and Lubricants on page 6-12.
6-8
At Least Once a Year
Starter Switch Check
{CAUTION:
When you are doing this inspection, the vehicle
could move suddenly. If the vehicle moves, you or
others could be injured.
1. Before starting this check, be sure there is enough
room around the vehicle.
2. Firmly apply both the parking brake and the regular
brake. SeeParking Brake on page 2-34.
Do not use the accelerator pedal, and be ready to
turn off the engine immediately if it starts.
3. Try to start the engine in each gear. The vehicle
should start only in P (Park) or N (Neutral). If the
vehicle starts in any other position, contact your
dealer/retailer for service.
Automatic Transmission Shift Lock
Control System Check
{CAUTION:
When you are doing this inspection, the vehicle
could move suddenly. If the vehicle moves, you or
others could be injured.
1. Before starting this check, be sure there is enough
room around the vehicle. It should be parked on a
level surface.
2. Firmly apply the parking brake. SeeParking Brake
on page 2-34.
Be ready to apply the regular brake immediately if
the vehicle begins to move.
3. With the engine off, turn the ignition to ON/RUN, but
do not start the engine. Without applying the regular
brake, try to move the shift lever out of P (Park) with
normal effort. If the shift lever moves out of P (Park),
contact your dealer/retailer for service.
6-10
Ignition Transmission Lock Check
While parked, and with the parking brake set, try to turn
the ignition to LOCK/OFF in each shift lever position.
The ignition should turn to LOCK/OFF only
when the shift lever is in P (Park).
The ignition key should come out only in
LOCK/OFF.
Contact your dealer/retailer if service is required.
Parking Brake and Automatic
Transmission P (Park) Mechanism
Check
{CAUTION:
When you are doing this check, the vehicle could
begin to move. You or others could be injured and
property could be damaged. Make sure there is
room in front of the vehicle in case it begins to roll.
Be ready to apply the regular brake at once should
the vehicle begin to move.Park on a fairly steep hill, with the vehicle facing downhill.
Keeping your foot on the regular brake, set the parking
brake.
To check the parking brake’s holding ability: With the
engine running and the transmission in N (Neutral),
slowly remove foot pressure from the regular brake
pedal. Do this until the vehicle is held by the parking
brake only.
To check the P (Park) mechanism’s holding ability:
With the engine running, shift to P (Park). Then
release the parking brake followed by the regular
brake.
Contact your dealer/retailer if service is required.
Underbody Flushing Service
At least every spring, use plain water to ush any
corrosive materials from the underbody. Take care
to clean thoroughly any areas where mud and other
debris can collect.
Tire Sealant and Compressor Kit
If the vehicle has a Tire Sealant and Compressor
Kit, check the sealant expiration date printed on
the instruction label of the kit at least once a year.
See your dealer/retailer for a replacement canister.
6-11