headlamp GMC YUKON 1999 Owner's Guide

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CAUTION:
Snow can trap exhaust gases under your vehicle.
This can cause deadly CO (carbon monoxide) gas
to get inside. CO could overcome you and kill
you. You can't see it or smell it, so you might not
know it is in your vehicle. Clear away snow from
around the base of your vehicle, especially any
that is blocking your exhaust pipe. And check
around again from time to time to be sure snow
doesn't collect there.
Open a window just a little on the side of the
vehicle that's away from the wind. This will help
keep CO out.
Run your engine only as long as you must. This saves
fuel. When you run the engine, make it go a little faster
than just idle. That is, push the accelerator slightly. This
uses less fuel for the heat that you get and it keeps the
battery charged. You will need a well
-charged battery to
restart the vehicle, and possibly for signaling later on
with your headlamps. Let the heater run for a while.
Then, shut the engine off and close the window almost
all the way to preserve the heat. Start the engine again
and repeat this only when you feel really uncomfortable
from the cold. But do it as little as possible. Preserve the
fuel as long as you can. To help keep warm, you can get
out of the vehicle and do some fairly vigorous exercises
every half hour or so until help comes.

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Bulb Replacement
Before you replace any bulbs, be sure that all the lamps
are off and the engine isn't running. For the proper bulb
type, see ªReplacement Bulbsº in the Index. For any
bulb changing procedure not listed in this section,
contact your dealer's service department.
Halogen Bulbs
CAUTION:
Halogen bulbs have pressurized gas inside and
can burst if you drop or scratch the bulb. You or
others could be injured. Be sure to read and
follow the instructions on the bulb package.
Headlamps
Parking/Turn Signal Lamp Removal
1. Remove the two phillips-head screws on the side of
the parking/turn signal bulb assembly. The
parking/turn signal assembly must be removed to
provide clearance for headlamp removal.
2. Pull the parking/turn signal assembly toward the side
of the vehicle until the tabs are out of the grille.

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A. Turn Signal Bulb
B. Sidemarker Bulb
3. To remove a bulb, turn the socket counterclockwise
to remove it from the assembly.
4. Install the parking/turn signal lamp assembly by
sliding it from the side of the vehicle toward the
center until the tabs fully engage the grille.
5. Install and tighten the two phillips
-head screws.Headlamp Removal
1. Remove the parking/turn signal assembly as
described previously.
2. Remove the two turn signal bulb sockets and the
sidemarker bulb socket from the parking/turn signal
assembly by turning them counterclockwise.
3. Set the parking/turn signal assembly to the side.4. Remove the two bolts at the top of the radiator
support as shown.
5. Pull the headlamp assembly out.

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6. Turn the bulb counterclockwise and remove it.
7. Unplug the electrical connector.
8. Put the new bulb into the lens assembly and turn it
clockwise until it is tight.
9. Plug in the electrical connector.
10. Put the headlamp lens assembly back into the
vehicle. Install and tighten the two bolts.
11. Install the two turn signal bulb sockets and the
sidemarker bulb socket into the parking/turn signal
bulb assembly.
12. Install the parking/turn signal assembly. Install and
tighten the two phillips
-head screws.
Parking/Turn Signal Lamps
For the procedure to remove the parking/turn signal
lamps and sidemarker lamps, see ªHeadlampsº
previously in this section.
Fog Lamps
1. The fog lamp bulb assembly is located under the
front bumper.
2. Remove the fog lamp bulb socket by turning it
counterclockwise.

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NOTICE:
The wrong wheel can also cause problems with
bearing life, brake cooling, speedometer or
odometer calibration, headlamp aim, bumper
height, vehicle ground clearance and tire or tire
chain clearance to the body and chassis.
See ªChanging a Flat Tireº in the Index for
more information.
Used Replacement Wheels
CAUTION:
Putting a used wheel on your vehicle is
dangerous. You can't know how it's been used or
how far it's been driven. It could fail suddenly
and cause an accident. If you have to replace a
wheel, use a new GM original equipment wheel.
Tire Chains
NOTICE:
Don't use tire chains. They can damage your
vehicle because there's not enough clearance.
Use another type of traction device only if its
manufacturer recommends it for use on your
vehicle and tire size combination and road
conditions. Follow that manufacturer's
instructions. To help avoid damage to your
vehicle, drive slowly, readjust or remove the
device if it's contacting your vehicle, and don't
spin your wheels.
If you do find traction devices that will fit, install
them on the rear tires.

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Electrical System
Add-On Electrical Equipment
NOTICE:
Don't add anything electrical to your vehicle unless
you check with your dealer first. Some electrical
equipment can damage your vehicle and the
damage wouldn't be covered by your warranty.
Some add
-on electrical equipment can keep other
components from working as they should.
Your vehicle has an air bag system. Before attempting to
add anything electrical to your vehicle, see ªServicing
Your Air Bag
-Equipped Vehicleº in the Index.
Headlamps
The headlamp wiring is protected by a circuit breaker in
the lamp switch. An electrical overload will cause the
lamps to flicker on and off, or in some cases to remain
off. If this happens, have your headlamp wiring checked
right away.
Windshield Wipers
The windshield wiper motor is protected by a circuit
breaker and a fuse. If the motor overheats due to heavy
snow, etc., the wiper will stop until the motor cools.
Although the circuit is protected from electrical
overload, overload due to heavy snow, etc., may cause
wiper linkage damage. Always clear ice and heavy snow
from the windshield before using the windshield wipers.
If the overload is caused by some electrical problem and
not snow, etc., be sure to get it fixed.
Power Windows and Other Power Options
Circuit breakers in the fuse panel protect the power
windows and other power accessories. When the current
load is too heavy, the circuit breaker opens and closes.
This protects the circuit until the current load returns to
normal or the problem is fixed.

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Fuse/Circuit
BreakerUsage
1 Stop/TCC Switch, Buzzer, CHMSL,
Hazard Lamps, Stoplamps
2 Transfer Case
3 Courtesy Lamps, Cargo Lamp, Glove
Box Lamp, Dome/Reading Lamps,
Vanity Mirrors, Power MirrorsFuse/Circuit
BreakerUsage
4 Instrument Cluster, DRL Relay, Lamp
Switch, Keyless Entry, Low Coolant
Module, Illuminated Entry Module
5 Rear Comfort Controls
6 Cruise Control
7 Auxiliary Power Outlet
8 Crank
9 License Lamp, Parking Lamps,
Taillamps, Tailgate Lamps, Front
Sidemarkers, Fog Lamp Relay, Door
Switch Illumination, Fender Lamps,
Headlamp Switch Illumination
10 Air Bag System
11 Wiper Motor, Washer Pump
12 A/C, A/C Blower, High Blower Relay
13 Power Amp, Rear Liftglass, Cigarette
Lighter, Door Lock Relay, Power
Lumbar Seat
14 4WD Indicator, Cluster, Front and Rear
Comfort Controls, Instrument Switches,
Radio Illumination, Chime Module

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Fuse/Circuit
BreakerUsage
15 DRL Relay, Fog Lamp Relay
16 Front and Rear Turn Signals,
Back
-Up Lamps, BTSI Solenoid
17 Radio (Ignition)
18 4WAL/VCM, ABS, Cruise Control
19 Radio (Battery)
20 PRNDL, Automatic Transmission,
Speedometer, Check Gages,
Warning Lights
21 Security/Steering
22 Auxiliary Power, Headlamp Delay
23 Rear Wiper, Rear Washer Pump
24 Front Axle, 4WD Indicator Lamp,
TP2 Relay
A Power Door Lock, Six
-Way Power
Seat, Keyless Entry Module
B Power WindowsUnderhood Fuse/Relay Center
The underhood fuse/relay center is located in the rear of
the engine compartment near the brake fluid reservoir.
Move the retainer clips for the cover to access the
fuse block.
You can remove fuses with a fuse extractor. The fuse
extractor is mounted to the interior fuse block. To
remove fuses if you don't have a fuse extractor, hold the
end of the fuse between your thumb and index finger
and pull straight out.

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Name Circuits Protected
ECM
-B Fuel Pump, PCM/VCM
RR DEFOG Rear Window Defogger
IGN
-E Auxiliary Fan Relay Coil, A/C
Compressor Relay, Hot Fuel Module
FUEL SOL Not Used
GLOW PLUG Not UsedName Circuits Protected
HORN Horn, Underhood Lamp
AUX FAN Auxiliary Fan
ECM
-1 Injectors, PCM/VCM
HTD ST
-FR Heated Front Seats
A/C Air Conditioning
HTD MIR Heated Outside Mirrors
ENG
-1 Ignition Switch, EGR, Canister
Purge, EVRV Idle Coast Solenoid,
Heated O
2
HTD ST-RR Heated Rear Seats
LIGHTING Headlamp and Panel Dimmer
Switch, Fog and Courtesy Fuses
BATT Battery, Fuse Block Busbar
IGN
-A Ignition Switch
IGN
-B Ignition Switch
ABS Anti
-Lock Brake Module
BLOWER Hi Blower and Rear Blower Relays
STOP/HAZ Stoplamps
HEATED
SEATSHeated Seats

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Replacement Bulbs
LAMP OR BULB TRADE NO.POWER RATING
AT 12.8V, WATTSQTY
HEADLAMPS
Low Beam 9006 HB4 55 2
High Beam 9005 HB3 65 2
LAMP OR BULB TRADE NO. QTY
EXTERIOR
Front Marker Lamp 194 2
Front Parking and Turn Lamp 2357NA 4
Rear Parking Lamp 3057 2
Rear Stop and Turn Lamp 3057 2
Back
-up Lamp3156 2
License Plate Lamp 194 2
Underhood Lamp 93 1
Fog Lamp 894 2
Continued