2005 GMC SIERRA brake

Camper/Fifth-Wheel Trailer Wiring Package
The eight-wire camper harness is located under the
front edge of the pickup box on the driver’s side of the
vehicle, attached to the frame bracket. A connector
will have to be added to the wiring harness which
connects to the camper.
The eight-wire harness contains the following
camper/trailer circuits:
Yellow: Left Stop/Turn Signal
Dark Green: Right Stop/Turn Signal
Brown: Taillamps
White: Ground
Light Green: Back-up Lamps
Light Blue: Center High-Mounted Stoplamp
(CHMSL)
Red: Battery Feed
Dark Blue: Trailer BrakeIf your vehicle is equipped with the “Heavy-Duty
Trailering” option, please refer to “Heavy-Duty Trailer
Wiring Package” earlier in this section.
When the camper-wiring harness is ordered without the
heavy-duty trailering package, an eight-wire harness
with a seven-pin connector and separate CHMSL
connector are located at the rear of the vehicle and are
tied to the vehicle’s frame.
4-94

Electric Brake Control Jumper
{CAUTION:
Be sure to use only the correct trailer brake
harness, the one intended for use on your
vehicle. If you use some other trailer brake
harness, even if it seems to t, your trailer
brakes may not work at all. You could have a
crash in which you or others could be injured.
Use only the trailer brake harness intended for
your vehicle. If it is no longer available to you,
be sure to get a proper replacement from
your dealer.This harness is included with your vehicle as part of the
heavy-duty trailer wiring package.
This harness is for an electric brake controller and
includes a trailer battery feed fuse. It should be installed
by your dealer or a qualied service center.
4-95

Power Take-Off (PTO)
Before using a Power Take-Off (PTO), if equipped, refer
to the manufacturer’s or installer’s instructions.
To engage a PTO on a vehicle with a manual
transmission do the following:
1. Hold the clutch pedal down.
2. Set the parking brake.
3. Shift the transmission into NEUTRAL.
4. Engage the PTO. Refer to the manufacturer’s
or installer’s for instructions on electrically
engaged PTOs.
5. For mobile operations, shift the transmission into
the gear you want, apply the regular brakes and
release the parking brake. For stationary operations,
leave the parking brake applied.
6. Release the clutch and regular brakes as you
normally would. When the clutch is released,
the PTO will start.
7. Turn the PTO rotary switch to ON.To engage a PTO on a vehicle with an automatic
transmission do the following:
1. For stationary use shift the transmission into
PARK (P).
2. Turn the PTO rotary switch ON.
3. If the engine speed is below the PTO engage
speed limit, the PTO will start. The blinking LED
on the PTO control switch indicates PTO engage is
requested. When PTO engages the LED will
switch from blinking to a steady light.
To use PTO speed control in Preset Mode (Factory
Setting) do the following:
1. Engage the PTO.
2. Select PARK (P) or NEUTRAL (N) range. Apply the
parking brake if NEUTRAL (N) is selected. Torque
Converter Clutch (TCC) is not available in
NEUTRAL (N) and is available only in PARK (P)
when engine speed is above 1,100 rpm.
3. Make sure your foot is off the brake pedal (and off
the clutch on vehicles equipped with a manual
transmission).
4. Select the desired engine speed for PTO operation.
Read the following preset mode information
regarding operation.
4-98

Preset Mode:PTO speed control mode is used for
stationary applications. (PTO will remain engaged while
mobile in the preset mode, however PTO set and
resume speed controls will be inoperative.) This mode
provides a default standby speed of 800 or 850 rpm
(depending on the engine/transmission combination) and
two default PTO control speeds which follow:
1. PTO Set Speed of 1,250 rpm, or
2. PTO Resume Speed of 1,700 rpm.
Please note that the standby speed (800/850 rpm) is
not to be used as a PTO control speed. Vehicles
not equipped with cruise control will not have the resume
speed capability.
To use PTO speed control in variable mode (while
mobile) do the following:
1. Engage the PTO.
2. Vehicle speed must be greater than 5 mph.
3. Make sure your foot is off the brake pedal (and off
the clutch for vehicles equipped with a manual
transmission).
4. Select the desired engine speed by using the foot
pedal, and select SET on the PTO switch or the
cruise control.To use PTO speed control in variable mode (while
stationary) do the following:
1. Engage the PTO.
2. Vehicle speed must be less than 5 mph.
3. Make sure your foot is off the brake pedal (and off
the clutch for vehicles equipped with a manual
transmission).
4. Select the desired engine speed by using the foot
pedal, and select SET on the PTO switch or the
cruise control.
Variable Mode:PTO speed control mode can be used
for both stationary and mobile applications. This
mode allows PTO to be controlled in a fashion similar to
how cruise control sets vehicle speed. The operator
can set to an rpm (between 800 and 2,200) with
the cruise control feature or with the SET position on
the PTO switch. The operator is then able to increase
rpm in increments of 100, or “tap up” with the resume
position on the cruise control. The operator can
also decrease rpm in increments of 100 with the SET
switch on the PTO or the cruise control.
Vehicles not equipped with cruise control will not have
the “tap up” capability.
4-99

Service............................................................5-4
Doing Your Own Service Work.........................5-5
Adding Equipment to the Outside
of Your Vehicle...........................................5-6
Fuel................................................................5-6
Gasoline Octane............................................5-6
Gasoline Specications....................................5-7
California Fuel...............................................5-7
Additives.......................................................5-7
Fuel E-85 (85% Ethanol).................................5-8
Fuels in Foreign Countries...............................5-9
Filling Your Tank..........................................5-10
Filling a Portable Fuel Container.....................5-12
Checking Things Under the Hood....................5-12
Hood Release..............................................5-13
Engine Compartment Overview.......................5-14
Engine Oil (Gasoline Engine)..........................5-20
Engine Oil Life System (Gasoline Engine)........5-23
Engine Air Cleaner/Filter................................5-25
Automatic Transmission Fluid
(Except Allison Transmission
®) ....................5-27
Automatic Transmission Fluid
(Allison Transmission
®) ...............................5-30
Manual Transmission Fluid.............................5-33
Hydraulic Clutch...........................................5-34Engine Coolant.............................................5-35
Coolant Surge Tank Pressure Cap..................5-37
Engine Overheating.......................................5-37
Overheated Engine Protection Operating
Mode (V8 Engines Only)............................5-39
Cooling System............................................5-40
Engine Fan Noise.........................................5-45
Power Steering Fluid.....................................5-46
Windshield Washer Fluid................................5-48
Brakes........................................................5-49
Battery........................................................5-52
Jump Starting...............................................5-53
Rear Axle.......................................................5-58
Four-Wheel Drive............................................5-58
Front Axle......................................................5-60
Noise Control System.....................................5-61
Tampering with Noise Control System
Prohibited.................................................5-61
Bulb Replacement..........................................5-62
Halogen Bulbs..............................................5-62
Headlamps..................................................5-63
Front Turn Signal, Sidemarker and
Daytime Running Lamps.............................5-64
Roof Marker Lamps......................................5-65
Section 5 Service and Appearance Care
5-1

Filling a Portable Fuel Container
{CAUTION:
Never ll a portable fuel container while it is in
your vehicle. Static electricity discharge from
the container can ignite the gasoline vapor.
You can be badly burned and your vehicle
damaged if this occurs. To help avoid injury to
you and others:
Dispense gasoline only into approved
containers.
Do not ll a container while it is inside a
vehicle, in a vehicle’s trunk, pickup bed or
on any surface other than the ground.
Bring the ll nozzle in contact with the
inside of the ll opening before operating
the nozzle. Contact should be maintained
until the lling is complete.
Do not smoke while pumping gasoline.
Checking Things Under
the Hood
{CAUTION:
An electric fan under the hood can start up
and injure you even when the engine is not
running. Keep hands, clothing and tools away
from any underhood electric fan.
{CAUTION:
Things that burn can get on hot engine parts
and start a re. These include liquids like fuel,
oil, coolant, brake uid, windshield washer and
other uids, and plastic or rubber. You or
others could be burned. Be careful not to drop
or spill things that will burn onto a hot engine.
5-12

A. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-25.
B. Coolant Surge Tank and Pressure Cap. SeeEngine
Coolant on page 5-35andCoolant Surge Tank
Pressure Cap on page 5-37.
C. Air Filter Restriction Indicator (If Equipped). See
Engine Air Cleaner/Filter on page 5-25.
D. Engine Oil Dipstick. See “Checking Engine Oil”
underEngine Oil (Gasoline Engine) on page 5-20.
E. Automatic Transmission Fluid Dipstick (If Equipped).
See “Checking the Fluid Level” underAutomatic
Transmission Fluid (Except Allison Transmission
®)
on page 5-27orAutomatic Transmission Fluid
(Allison Transmission
®) on page 5-30.
F. Electric Engine Cooling Fan (If Equipped). See
Cooling System on page 5-40.
G. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil (Gasoline Engine) on page 5-20.H. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-46.
I. Remote Negative (−) Terminal (GND). SeeJump
Starting on page 5-53.
J. Remote Positive (+) Terminal. SeeJump Starting on
page 5-53.
K. Brake Fluid Reservoir. See “Brake Fluid” under
Brakes on page 5-49.
L. Clutch Fluid Reservoir (If Equipped). SeeHydraulic
Clutch on page 5-34.
M. Underhood Fuse Block. SeeUnderhood Fuse Block
on page 5-125.
N. Battery. SeeBattery on page 5-52.
O. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-48.
5-15

A. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-25.
B. Coolant Surge Tank and Pressure Cap. SeeEngine
Coolant on page 5-35andCoolant Surge Tank
Pressure Cap on page 5-37.
C. Air Filter Restriction Indicator (If Equipped). See
Engine Air Cleaner/Filter on page 5-25.
D. Engine Oil Dipstick. See “Checking Engine Oil”
underEngine Oil (Gasoline Engine) on page 5-20.
E. Automatic Transmission Fluid Dipstick (If Equipped).
See “Checking the Fluid Level” underAutomatic
Transmission Fluid (Except Allison Transmission
®)
on page 5-27orAutomatic Transmission Fluid
(Allison Transmission
®) on page 5-30.
F. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil (Gasoline Engine) on page 5-20.
G. Electric Engine Cooling Fan (If Equipped). See
Cooling System on page 5-40.H. Remote Negative (−) Terminal (GND). SeeJump
Starting on page 5-53.
I. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-46.
J. Remote Positive (+) Terminal. SeeJump Starting on
page 5-53.
K. Brake Fluid Reservoir. See “Brake Fluid” under
Brakes on page 5-49.
L. Clutch Fluid Reservoir (If Equipped). SeeHydraulic
Clutch on page 5-34.
M. Underhood Fuse Block. SeeUnderhood Fuse Block
on page 5-125.
N. Battery. SeeBattery on page 5-52.
O. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-48.
5-17