2003 GMC SIERRA lock

A. Push and Pull
B. Rotate Tire
7. Make sure the tire is stored securely. Push, pull,
and then try to rotate or turn the tire. If the tire
moves, use the wheel wrench to tighten the cable.
Reinstall the spare tire lock (if equipped).
Secondary Latch System
Your vehicle has an underbody mounted tire hoist
assembly equipped with a secondary latch system.
It’s designed to stop the spare tire from suddenly falling
off your vehicle. For the secondary latch to work, the
spare must be installed with the valve stem pointing
down. See“Storing a Flat or Spare Tire, Jack and Tools”
earlier in this section.
{CAUTION:
Before beginning this procedure read all the
instructions. Failure to read and follow the
instructions could damage the hoist assembly
and you and others could get hurt. Read and
follow the instructions listed below.
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To release the spare tire from the secondary latch do
the following:
1. Check under the vehicle to see if the cable end is
visible.
2. If the cable is not visible proceed to Step 6.
If it is visible,first try to tighten the cable by turning
the wheel wrench clockwise until you hear two
clicks or feel it skip twice. You cannot overtighten
the cable.
3. Loosen the cable by turning the wrench
counterclockwise three or four turns.4. Repeat this procedure at least two times. If the
spare tire lowers to the ground, continue with
Step 5 of“Removing the Spare Tire and Tools”
earlier in this section.
5. Turn the wrench counterclockwise until
approximately six inches (15 cm) of cable is
exposed.
6. Stand the wheel blocks
on their shortest ends,
with the backs
facing each other.
7. Place the bottom edge of the jack on the wheel
blocks, separating them so that the jack is
balanced securely.
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8. Attach the jack handle, extension, and wheel
wrench to the jack and place it (with the wheel
blocks) under the vehicle towards the front of the
rear bumper. Position the center lift point of the jack
under the center of the spare tire.
9. Turn the wrench clockwise to raise the jack until it
lifts the endfitting.
10. Continue raising the jack until the spare tire stops
moving upward and is heldfirmly in place. The
secondary latch has released and the spare tire is
balancing on the jack.
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11. Lower the jack by turning the wheel wrench
counterclockwise. Keep lowering the jack until the
spare tire slides off the jack or is hanging by
the cable.
{CAUTION:
Someone standing too close during the
procedure could be injured by the jack. If the
spare tire does not slide off the jack
completely, make sure no one is behind you or
on either side of you as you pull the jack out
from the spare.
12. Disconnect the jack handle from the jack
and carefully remove the jack. Use one hand
to push against the spare whilefirmly pulling the
jack out from under the spare tire with the
other hand.
If the spare tire is hanging from the cable, insert the
hoist handle, extension and wheel wrench into
the hoist shaft hole in the bumper and turn
the wheel wrench counterclockwise to lower the
spare the rest of the way.13. Tilt the retainer at the
end of the cable and
pull it through the
wheel opening. Pull the
tire out from under
the vehicle.
14. If the cable is hanging under the vehicle, turn the
wheel wrench clockwise to raise the cable back up.
Have the hoist assembly inspected as soon as you can.
You will not be able to store a spare orflat tire using
the hoist assembly until it has been replaced.
To continue changing theflat tire, see“Removing the
Flat Tire and Installing the Spare Tire”earlier in
this section.
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Instrument Panel Fuse Block
The fuse block access
door is on the driver’s side
edge of the instrument
panel. Pull off the cover to
access the fuse block.
To remove fuses, hold the end of the fuse between your
thumb and indexfinger and pull straight out.
You may have spare fuses located behind the fuse
block access door. These can be used to replace a bad
fuse. However, make sure it is of the correct amperage.
Fuses Usage
RR Wiper Not Used
SEO ACCYSpecial Equipment Option
Accessory
WS WPR Windshield Wipers
TBC ACCYTruck Body Controller
Accessory
IGN 3 Ignition, Heated Seats
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Fuses Usage
4WDFour-Wheel Drive System,
Auxiliary Battery
HTR A/C Climate Control System
LOCK (Relay)Power Door Lock Relay
(Lock Function)
HVAC 1 Climate Control System
L DOORDriver’s Door Harness
Connection
CRUISECruise Control, Power Take
Off (PTO)
UNLOCK (Relay)Power Door Lock Relay
(Unlock Function)
RR FOG LP Not Used
BRAKE Anti-Lock Brake System
DRIVER UNLOCKPower Door Lock Relay
(Driver’s Door Unlock
Function)
IGN 0 TCM
TBC IGN 0 Truck Body Controller
VEH CHMSLVehicle and Trailer High
Mounted StoplampFuses Usage
LT TRLR ST/TRN Left Turn Signal/Stop Trailer
LT TRNLeft Turn Signals and
Sidemarkers
VEH STOPVehicle Stoplamps, Brake
Module, Electronic Throttle
Control Module
RT TRLR ST/TRN Right Turn Signal/Stop Trailer
RT TRNRight Turn Signals and
Sidemarkers
BODY Harness Connector
DDM Driver Door Module
AUX PWR 2 Not Used
LOCKS Power Door Lock System
ECC Not Used
TBC 2C Truck Body Controller
FLASH Flasher Module
CB LT DOORSLeft Power Windows Circuit
Breaker
TBC 2B Truck Body Controller
TBC 2A Truck Body Controller
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Center Instrument Panel Fuse Block
The center instrument panel utility block is located
underneath the instrument panel, to the left of the
steering column.
Device Usage
SEO Special Equipment Option
TRAILER Trailer Brake Wiring
UPFIT Upfitter (Not Used)
SL RIDERide Control Harness
Connection
HDLR 2 Headliner Wiring Connector
BODY Body Wiring Connector
DEFOG Rear Defogger Relay
HDLNR 1 Headliner Wiring Connector 1
SPARE RELAY Not Used
CB SEATDriver and Passenger Seat
Module Circuit Breaker
CB RT DOORRight Power Windows Circuit
Breaker
SPARE Not Used
INFOInfotainment Harness
Connection
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Underhood Fuse BlockThe underhood fuse block in the engine compartment
on the driver’s side of the vehicle near the battery.
Lift the cover for access to the fuse/relay block.
To remove fuses hold the end of the fuse between your
thumb and indexfinger and pull straight out.
SeeEngine Compartment Overview on page 5-12for
more information on its location.
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