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Fuses Usage
01 Passenger Door Control Module
02 Driver Door Control Module
03 Liftgate Module 2
04 Truck Body Controller 3
05 Blank
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 Blank
14 Driver Side Rear Parking LampsFuses Usage
15 Blank
16Vehicle Center High-Mounted
Stoplamp (CHMSL)
17Passenger Side Rear Parking
Lamps
18 Locks
19 Liftgate Module/Driver Seat Module
20 Blank
21 Locks
23 Blank
24 Unlock
25 Ignition 0
26 Overhead Battery/OnStar
®System
27 Rainsense™ Wipers
28 Sunroof
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Fuses Usage
29 Accessory
30 Parking Lamps
31 Truck Body Controller Accessory
32 Truck Body Controller 5
33 Front Wipers
34 Ignition 3
35 Vehicle Stop
36 Transmission Control Module
37 Heat Ventilation Air Conditioning B
38 Front Parking Lamps
39 Rear Left Turn Signal
40 Heat, Ventilation, Air Conditioning 1
41 Front Right Turn SignalFuses Usage
42 Radio
43 Trailer Park
44 Rear Right Turn Signal
45 Blank
46 Auxiliary Power 1
47 Blank
48 Ignition 0
49 Not Used
50 Blank
51 Front Left Turn Signal
52 Brakes
53 Truck Body Controller 4
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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 you start, be sure you have enough
room around the vehicle.
2. Firmly apply both the parking brake and the
regular brake. SeeParking Brake on
page 116.
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 PARK (P) or
NEUTRAL (N). If the vehicle starts in any
other position, contact your dealer 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 you start, be sure you have enough
room around the vehicle. It should be parked
on a level surface.
2. Firmly apply the parking brake. SeeParking
Brake on page 116.
Be ready to apply the regular brake
immediately if the vehicle begins to move.
3. With the engine off, turn the ignition to RUN,
but do not start the engine. Without applying
the regular brake, try to move the shift lever
out of PARK (P) with normal effort. If the shift
lever moves out of PARK (P), contact your
dealer for service.
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Ignition Transmission Lock Check
While parked, and with the parking brake set, try to
turn the ignition to LOCK in each shift lever position.
The ignition should turn to LOCK only when the
shift lever is in PARK (P).
The ignition key should come out only in LOCK.
Contact your dealer if service is required.
Parking Brake and Automatic
Transmission Park (P) Mechanism Check
{CAUTION:
When you are doing this check, your
vehicle could begin to move. You or others
could be injured and property could be
damaged. Make sure there is room in front
of your 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 transmission in
NEUTRAL (N), slowly remove foot pressure
from the regular brake pedal. Do this until the
vehicle is held by the parking brake only.
To check the PARK (P) mechanism’s holding
ability: With the engine running, shift to
PARK (P). Then release the parking brake
followed by the regular brake.
Contact your dealer 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.
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