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Fuses Usage
21 Locks
22 Blank
23 Blank
24 Unlock
25 Ignition 0
26 Overhead Battery/OnStar
®System
27 Rainsense Wipers
28 Sunroof
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
Fuses Usage
38 Front Parking Lamps
39 Rear Left Turn Signal
40 Heat, Ventilation, Air Conditioning 1
41 Front Right Turn Signal
42 Radio
43 Trailer Park
44 Rear Right Turn Signal
45 Blank
46 Auxiliary Power 1
47 Blank
48 Ignition 0
49 Four Wheel Drive
50 Blank
51 Front Left Turn Signal
52 Brakes
53 Truck Body Controller 4
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Additional Required Services (cont’d)
Service and Miles (Kilometers)25,000
(40 000)50,000
(80 000)75,000
(120 000)100,000
(160 000)125,000
(200 000)150,000
(240 000)
Engine cooling system service (or every
ve years, whichever occurs rst).
An Emission Control Service.
See footnote (i).•
Inspect engine accessory drive belt.
An Emission Control Service.
See footnote (l).•
Maintenance Footnotes
(a)Visually inspect brake lines and hoses for proper
hook-up, binding, leaks, cracks, chafing, etc. Inspect disc
brake pads for wear and rotors for surface condition.
Inspect other brake parts, including calipers, parking
brake, etc.
(b)Visually inspect front and rear suspension and
steering system for damaged, loose, or missing parts or
signs of wear. Inspect power steering lines and hoses for
proper hook-up, binding, leaks, cracks, chafing, etc.(c)Visually inspect hoses and have them replaced if
they are cracked, swollen, or deteriorated. Inspect all
pipes, fittings and clamps; replace with genuine parts as
needed. To help ensure proper operation, a pressure test
of the cooling system and pressure cap and cleaning the
outside of the radiator and air conditioning condenser is
recommended at least once a year.
(d)Inspect wiper blades for wear, cracking, or
contamination. Clean the windshield and wiper blades, if
contaminated. Replace wiper blades that are worn or
damaged. See Windshield Wiper Blade Replacement on
page 5-56 and Windshield, Backglass, and Wiper Blades
on page 5-102 for more information.
6-7
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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 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 2-27.
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 2-27.
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
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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.
6-11
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