1999 GMC C-SERIES door lock

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6-71
Name Circuits Protected
CHAS Exhaust Brake, Air Suspension
Dump Valve, Air Dryer, HYD
ABS ECHU
PARK LP Auxiliary Wiring, Air Conditioner
Controls, Parking Lamps, Turn
Signals, Taillamps, Stoplamps,
Marker Lamps, Trailer Running
Lamps, Lighted Mirrors, Radio
Receiver, Mirror Clearance Lamps
HORN Horn/Diagnostic Connector
PRK BRK Parking Brake Module
FUEL Heated Fuel Filter (Diesel
Engines) or Fuel Pump
(Gasoline Engines)
AXLE Heated Mirrors, Radiator Shutters,
Tw o
-Speed Axle Motor,
Tw o
-Speed Axle Switch
MRKR LP Roof Marker Lamps,
Trailer Marker Lamps,
Marker Lamp RelayName Circuits Protected
CIG/AUX Cigarette Lighter,
Auxiliary Power Jacks
AUX Auxiliary Wiring Relay
IGN RLY/VIN Vehicle Interface Module
(Diesel Engines) or Generator,
Coil, Injectors (Gasoline Engines)
WDO Power Windows
CRNK Starter Relay
IGN SW Instrument Panel Cluster Telltales
AUX Auxiliary Wiring
RDO Radio, Auxiliary Wiring
DR LK Power Door Locks
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6-73
Name Circuits/Circuit Breakers
Protected
STP/HAZ
TURNStop Lamp, Turn Signal/Hazard
Lights, Fuel, Ignition Relay
(Gasoline Engines)
IGN SW3 Air Conditioner, Ignition Switch,
Axle, ChassisName Circuits/Circuit Breakers
Protected
INT/EXT
LIGHTSParking Lamps,
Dome/Panel Lights
HEAD LAMP Headlamps,
Daytime Running Lamps
AUX WRG Auxiliary, Park Brake
IGN SW1 Ignition Switch, Wash/Wipe,
Crank, Radio
HYD PUMP Hydraulic Brake,
Brake Pump Motor
HYD ABS EHCU
PWR
WDO/LCKSWindow, Door Locks
PARK BRK Parking Brake Motor
BLOWER
HORNBlower, Horn, Cigarette
Lighter/Auxiliary
FUEL/ENGINE Empty
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7-24 At Least Twice a Year
Restraint System Check
Make sure the safety belt reminder light (if equipped)
and all your belts, buckles, latch plates, retractors and
anchorages are working properly. Look for any other
loose or damaged safety belt system parts. If you see
anything that might keep a safety belt system from
doing its job, have it repaired. Have any torn or frayed
safety belts replaced.
Wiper Blade Check
Inspect wiper blades for wear or cracking. Replace blade
inserts that appear worn or damaged or that streak or
miss areas of the windshield. Also see ªWiper Blades,
Cleaningº in the Index.
Weatherstrip Lubrication
Silicone grease on weatherstrips will make them last
longer, seal better, and not stick or squeak. Apply
silicone grease with a clean cloth. During very cold,
damp weather more frequent application may be
required. (See ªRecommended Fluids and Lubricantsº
in the Index.)Body Lubrication Service
Lubricate all surfaces such as door checks, door lock
bolts, lock strike plates, door hinge bushings and
dovetail bumper wedges. Where oil holes are provided,
a dripless oil can be used. The seat adjusters, seat track,
door weatherstrips and rubber hood bumpers should also
be lubricated.
Part C tells you what to use. More frequent lubrication may
be required when exposed to a corrosive environment.
Parking Brake Check
Park on a fairly steep hill and hold the vehicle with the
parking brake only. This checks holding ability.
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7-27
Door Latches Check
Check that doors close, latch and lock tightly. Check for
broken, damaged or missing parts that might prevent
tight latching.
Hood Latches Check
Check that the hood closes firmly. Check for broken,
damaged, loose or missing parts that might prevent tight
latching. Make sure the secondary latch (if equipped)
keeps the hood from opening all the way when the
primary latch is released.
Fluid Leaks Check
Check for fuel, coolant, oil or other fluid leaks by
looking at the surface beneath the vehicle after it has
been parked for a while.
Underbody Inspection
Corrosive materials used for ice, snow removal and dust
control can collect on the underbody. If these materials
are not removed, accelerated corrosion (rust) can occur
on underbody parts such as fuel lines, frame, floor pan
and exhaust system. At least every spring, flush these materials from the underbody with plain water. Take
care to clean well any areas where mud and other debris
can collect. Sediment packed in closed areas of the
frame should be loosened before being flushed.
Engine Cover Check
Check that the cab's engine cover and seal (if equipped)
are not torn or damaged. Be sure that the cover is bolted
down firmly to the floor.
At Least Once a Year
Key Lock Cylinders Service
Lubricate the key lock cylinders with the lubricant
specified in Part C.
Underbody Flushing Service
At least every spring, use plain water to flush any
corrosive materials from the underbody. Take care to
clean thoroughly any areas where mud and other debris
can collect.
Tractor Protection (Breakaway) Valve Check
On air brake models, remove, disassemble, clean and
inspect the tractor protection (breakaway) valve.
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9-3
Cooling System
Capacity 6-74 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Diesel Engines 5-27, 6-25 . . . . . . . . . . . . . . . . . . . . . . . . . .
Gasoline Engines 5-20, 6-23 . . . . . . . . . . . . . . . . . . . . . . . .
Crankcase Capacity 6-74 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cruise Control 2-36 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Customer Assistance for Text Telephone Users 8-3 . . . . . . . . .
Customer Assistance Information 8-1 . . . . . . . . . . . . . . . . . . .
Customer Satisfaction Procedure 8-2 . . . . . . . . . . . . . . . . . . . .
Damage
Finish 6-65 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Sheet Metal 6-64 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Daytime Running Lamps 2-44 . . . . . . . . . . . . . . . . . . . . . . . . .
Daytime Running Lamps Indicator Light 2-67 . . . . . . . . . . . .
Defects, Reporting Safety 8-6, 8-7 . . . . . . . . . . . . . . . . . . . . .
Defensive Driving 4-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Defogging 3-6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Diesel Engine Exhaust Brake 2-16 . . . . . . . . . . . . . . . . . . . . . .
Diff Lock Indicator Light 2-63 . . . . . . . . . . . . . . . . . . . . . . . . .
Do Not Shift Light 2-57 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Dome Lamps 2-46 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Door
Latches Check 7
-27 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Locks 2-4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Power Locks 2-4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Driver Position 1-11 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Driving
City 4
-19 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Defensive 4-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Drunken 4
-3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Freeway 4-20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
In a Blizzard 4-26 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
In Rain and on Wet Roads 4-16 . . . . . . . . . . . . . . . . . . . . . .
Night 4-15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
On Curves 4-10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
On Hill and Mountain Roads 4-22 . . . . . . . . . . . . . . . . . . . .
On Snow and Ice 4-24 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Through Water 4-18 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Winter 4-24 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Drunken Driving 4-3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Electrical Equipment, Adding 6-68 . . . . . . . . . . . . . . . . . . . .
Electrical System 6-68 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Engine
Air Cleaner Filter 6
-77 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Air Control 2-42 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Automatic Shutdown 2-11 . . . . . . . . . . . . . . . . . . . . . . . . . .
Coolant (Caterpillar
Diesel Engine) 6-27 . . . . . . . . . . . . .
Coolant (Gasoline Engine) 6-23 . . . . . . . . . . . . . . . . . . . . . .
Coolant Heater 2-15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Coolant Level Check 7-23 . . . . . . . . . . . . . . . . . . . . . . . . . .
Coolant Temperature Gage 2-62 . . . . . . . . . . . . . . . . . . . . .
Cooling System Capacity 6-74 . . . . . . . . . . . . . . . . . . . . . . .
Crankcase Capacity 6-74 . . . . . . . . . . . . . . . . . . . . . . . . . . .
Diesel,Warm-Up 2-11 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Exhaust 2-29, 2-30, 4-27 . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fan Breakage 6-3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fan Noise 5-33 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fast Idle System 2-12 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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9-6
Lamps 2-43 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Dome 2-46 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
On Reminder 2-44 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Latches, Seatback 1-3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Leaving Your Vehicle 2-5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lighter 2-47 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lights
Air Brake System Warning 2
-59 . . . . . . . . . . . . . . . . . . . . .
Anti-Lock Brake System Warning 2-61, 4-7 . . . . . . . . . . . .
Apply Park Brake Warning 2-60 . . . . . . . . . . . . . . . . . . . . .
Brake System Warning 2-57 . . . . . . . . . . . . . . . . . . . . . . . . .
Charging System Indicator 2-56 . . . . . . . . . . . . . . . . . . . . . .
Check Gages Indicator 2-67 . . . . . . . . . . . . . . . . . . . . . . . . .
Daytime Running Lamps Indicator 2-67 . . . . . . . . . . . . . . .
Diff Lock Indicator 2-63 . . . . . . . . . . . . . . . . . . . . . . . . . . .
Do Not Shift Warning 2-57 . . . . . . . . . . . . . . . . . . . . . . . . .
Hydraulic Brake System Warning 2-58 . . . . . . . . . . . . . . . .
Intake Heater Indicator 2-63 . . . . . . . . . . . . . . . . . . . . . . . . .
Lamp and Bulb Data 6-74 . . . . . . . . . . . . . . . . . . . . . . . . . .
Low Coolant Warning 2-62 . . . . . . . . . . . . . . . . . . . . . . . . .
Parking Brake Warning 2-60 . . . . . . . . . . . . . . . . . . . . . . . .
Parking Brake Indicator 2-60 . . . . . . . . . . . . . . . . . . . . . . . .
Safety Belt Reminder 1-7, 2-55 . . . . . . . . . . . . . . . . . . . . . .
Service Park Brake Warning 2-60 . . . . . . . . . . . . . . . . . . . .
Service Trans Filter Indicator 2-64 . . . . . . . . . . . . . . . . . . . .
Manual Fast Idle Indicator Light 2-62 . . . . . . . . . . . . . . . . .
Loading Your Vehicle 4-28 . . . . . . . . . . . . . . . . . . . . . . . . . . . Locks
Door 2
-4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Power Door 2-4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lubricants and Fluids 7-28 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lubrication Service, Body 7-24 . . . . . . . . . . . . . . . . . . . . . . . .
Maintenance Record 7-31 . . . . . . . . . . . . . . . . . . . . . . . . . . .
Owner Checks and Services 7-23 . . . . . . . . . . . . . . . . . . . . .
Recommended Fluids and Lubricants 7-28 . . . . . . . . . . . . .
Scheduled Maintenance Services 7-4 . . . . . . . . . . . . . . . . . .
Maintenance, Underbody 6-65 . . . . . . . . . . . . . . . . . . . . . . . . .
Malfunction Indicator Lamp 2-64 . . . . . . . . . . . . . . . . . . . . . .
Manual Fast Idle Indicator Light 2-62 . . . . . . . . . . . . . . . . . . .
Manual Transmission Fluid 6-19 . . . . . . . . . . . . . . . . . . . . . . .
Marker and Clearance Lamps 2-45 . . . . . . . . . . . . . . . . . . . . .
Maxi-Fuse Block 6-72 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Mirrors
Convex Outside 2
-46 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Heated Outside 2-47 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Inside Rearview 2-46 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Outside 2-46 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Model Reference vi. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Moisture Ejector 6
-33 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Mountain Roads 4-22 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muffler/Catalytic Converter Assembly 6-48 . . . . . . . . . . . . . .
Multifunction Lever 2-32 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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9-7
New Vehicle ªBreak-Inº 2-5 . . . . . . . . . . . . . . . . . . . . . . . . .
Night Vision 4-15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Noise Control System 6-11 . . . . . . . . . . . . . . . . . . . . . . . . . . .
Odometer 2-53 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Off-Road Recovery 4-12 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Oil, Engine 6-13, 6-17 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Owner Checks and Services 7-23 . . . . . . . . . . . . . . . . . . . . . . .
Owner Publications Order Form 8-9 . . . . . . . . . . . . . . . . . . . .
Owner Publications, Ordering 8-8 . . . . . . . . . . . . . . . . . . . . . .
Paint Spotting, Chemical 6-65 . . . . . . . . . . . . . . . . . . . . . . . .
Parking
Brake 2
-24 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Brake Check 7-24 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Brake Indicator Light 2-60 . . . . . . . . . . . . . . . . . . . . . . . . . .
Over Things That Burn 2-29 . . . . . . . . . . . . . . . . . . . . . . . .
Passing 4-12 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Power
Door Locks 2
-4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Option Fuses 6-69 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Steering 4-9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Steering Fluid 6-28 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Windows 2-31 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Power Take-Off (PTO) 4-31 . . . . . . . . . . . . . . . . . . . . . . . . . .
Pregnancy, Use of Safety Belts 1-21 . . . . . . . . . . . . . . . . . . . .
Pressure Caps 6-77 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Problems on the Road 5-1 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Publications, Service and Owner 8-8 . . . . . . . . . . . . . . . . . . . .
Radiator 5-25 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Radiator Pressure Cap 6-21 . . . . . . . . . . . . . . . . . . . . . . . . . . .
Radiator Shutters 2-13 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Radio Reception 3-10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Rear Axle 6-20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Airshift Control 2-19 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Differential Lock Control 2-41 . . . . . . . . . . . . . . . . . . . . . . .
Fluid Capacity 6-76 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Shift Motor 6-20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tw o-Speed Electric Shift Control 2-17 . . . . . . . . . . . . . . . .
Towing 5-15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Recovery Tank, Coolant 5-22 . . . . . . . . . . . . . . . . . . . . . . . . . .
Refrigerants, Air Conditioning 6-77 . . . . . . . . . . . . . . . . . . . .
Releasing Air Operated Parking Brake 5-15 . . . . . . . . . . . . . .
Remote Cassette Tape Player 3-10 . . . . . . . . . . . . . . . . . . . . . .
Replacement Wheels 6-57 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Replacing Safety Belts 1-36 . . . . . . . . . . . . . . . . . . . . . . . . . . .
Reporting Safety Defects 8-6, 8-7 . . . . . . . . . . . . . . . . . . . . . .
Restraints
Checking 1
-36 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Child 1-26 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Head 1-3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Replacing Parts After a Crash 1-36 . . . . . . . . . . . . . . . . . . .
System Check 7-24 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Right Passenger Position 1-21 . . . . . . . . . . . . . . . . . . . . . . . . .
Roadside Assistance 8-5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Rocking Your Vehicle 5-38 . . . . . . . . . . . . . . . . . . . . . . . . . . .
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