heater GMC SIERRA 1998 User Guide

If there seems to be no leak, start the engine again. See if
the engine cooling
fan speed increases when idle speed is
doubled
by pushing the accelerator pedal down. If it
doesn't, your vehicle needs service. Turn off the engine.
How to Add Coolant to the Coolant
Recovery Tank -- Gasoline Engines
If you haven't found a problem yet, but the coolant level
isn't at or above the COLD mark, add
a 50/50 mixture
of C'IC~LIII r.tuter- (preferably distilled) and DEX-COOL@
engine coolant at the coolant recovery tank. (See
"Engine Coolant"
in the Index for more information.)
I A CAUTION: I
I CAUTION: (Continued)
Adding only plain water to your cooling system
can be dangerous. Plain water, or some other
liquid like alcohol, can boil before the proper
coolant mix will. Your vehicle's coolant warning
system
is set for the proper coolant mix.
CAUTION: (Continued) With plain water or the wrong mix,
your engine
could get
too hot but you wouldn't get the
overheat warning. Your engine could catch
fire
and you or others could be burned. Use a 50/50
mix of clean water and DEX-COOL%oolant.
I NOTICE:
In cold weather, water can freeze and crack the
engine, radiator, heater core and other parts. Use the recommended coolant and the proper
coolant mixture.
5-17
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NOTICE:
When adding coolant, it is important that you use
only
DEX-COOL@ (silicate-free) coolant.
If coolant other than DEX-COOL is added to the
system, premature engine, heater core or
radiator corrosion may result. In addition, the
engine coolant will require change sooner
-- at
30,000 miles (50 000 km) or 24 months,
whichever occurs first. Damage caused by the use
of coolant other than DEX-COOL@ is not
covered by your new vehicle warranty.
What to Use
Use a mixture of one-half clean water (preferably
distilled) and one-half
DEX-COOL@ coolant which
won’t damage aluminum
parts. If you use this mixture,
you don’t need to add anything else.
CAUTION:
Adding only plain water to your cooling system
can be dangerous. Plain water, or some other
liquid like alcohol, can boil before the proper
coolant mixture will. Your vehicle’s coolant
warning system is set for the proper coolant
mixture. With plain water or the wrong mixture,
your engine could get too hot but you wouldn’t
get the overheat warning. Your engine could
catch fire and you or others could be burned.
Use a
50/50 mixture of clean water and
DEX-COOL@ coolant.
6-29
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- ~ ~~
NOTICE:
If you use an improper coolant mixture, your
engine could overheat and be badly damaged.
The repair cost wouldn’t be covered by your
warranty.
Too much water in the mixture can
freeze and crack the engine, radiator, heater core
and other parts.
If you have to add coolant more than four times a year,
have your dealer check your cooling system.
NOTICE:
If you use the proper coolant, you don’t have to
add extra inhibitors or additives which claim
to
improve the system. These can be harmful.
Checking Coolant
If your vehicle has a diesel engine, see “Checking
Coolant”
in the Diesel Engine Supplement.
,:. . .,. ..... I.. .;> .:... ...,,.. ::l:. ..
.. .
The coolant recovery tank is located on the passenger’s
side at the rear corner
of the engine compartment.
When your engine
is cold, the coolant level should be at
the
COLD mark, or a little higher. When your engine is
warm,
the level should be up to the HOT mark, or a
little higher.
6-30
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STARTER RELAY
[-I
[-I
[T)
I BLOWER
n STOPiHAZ
Name
ECM-B RR DEFOG
IGN-E
FUEL
SOL
GLOW PLUG
Usage
Horn, Underhood Lamps
Auxiliary Fan
Injectors, PCM/VCM
Not Used
Air Conditioning
Not Used
Ignition Switch, EGR, Canister
Purge, EVRV Idle Coast Solenoid,
Heated
02, Fuel Heater
(Diesel Engine), Water Sensor
(Diesel Engine)
HTD ST-RR Not Used
LIGHTING Headlamp and Panel Dimmer
BATT Battery, Fuse Block Busbar
IGN-A Ignition Switch
IGN-B Ignition Switch Switch,
Fog and Courtesy Fuses
ABS Anti-Lock Brake Module
BLOWER High Blower Relay
STOP/HAZ Stoplamps
HEATED SEATS Not Used
6-75
Usage
Fuel Pump, PCM/VCM
Rear Window Defogger
Auxiliary Fan Relay Coi
il, AIC
Compressor Relay, Hot Fuel
Module, Dual Tanks
Fuel Solenoid (Diesel Engine)
Glow Plugs (Diesel Engine)
Name
HORN
AUX FAN
ECM- 1
HTD ST-FR
AIC HTD MIR
ENG-
1
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Vinyl ....................................... 6-63
Wheels
..................................... 6-67
Windshield and Wiper Blades
................... 6-65
Clock. Setting the ................................ 3-7
Clutch Fluid. Hydraulic
..................... 6-25. 7-46
Clutch. System Check
........................... 7-41
Comfort Controls
................................ 3-2
Comfort Guides. Rear
........................... 1-40
Compact Disc Care
............................. 3-26
Compact Disc Player
.......................
3-16 . 3-20
Compact Disc Player Care
........................ 3-26
Compass. Rearview Mirror
with ................... 2-46
Console Storage
................................ 2-54
Control
of a Vehicle .............................. 4-5
Convex Outside Mirror .......................... 2-SO
Coolant ............................. 6-28.6-79.7-46
Heater
. Engine ............................... 2- 14
Recovery Tank ............................... 5- I5
Cooling System ................................ 5- IS
Courtesy Transportation ........................... 8-8
Cruise Control
................................. 2-38
Cupholders
.......................... 2.54.2.55. 2-56
Customer Assistance Information ................... 8- I
Customer Satisfaction Procedure .................... 8-2
Climate Control System ....................... 3.2 . 3-3
Customer Assistance for Text Telephone Users
......... 8-4
Damage. Finish
............................... 6-68
Darnage. Sheet Metal
............................ 6-67
Daytime Running Lamps
......................... 2-42
Daytime Running Lamps Indicator Lighl
............ 2-74
Dead Battery
................................... 5-3
Defects. Reporting Safety ........................ 8- 10
Defensive Driving ............................... 4-2
Defogger. Rear Window .......................... 3-6
Defoggng
and Defrosting ......................... 3-6
Dolby B Noise Reduction
....................... 3-15
Dome Lamps
.................................. 2-44
DO0
I.
Locks ....................................... 2-5
Storage Pocket ............................... 2-51
Third
........................................ 2-4
Downshifting
.................................. 2-20
Driver Position ................................. 1-14
Driving City
........................................ 4-31
Defensive
.................................... 4-2
Drunken
..................................... 4-3
Freeway
.................................... 4-32
In a Blizzard ................................. 4-38
In the Rain .................................. 4-28
Night
...................................... 4-27
Off-Road
................................... 4-14
On Curves
................................... 4-9
On Grades While Towing a Trailer ............... 4-58
On Hill and Mountain Roads .................... 4-34
On Snow and Ice
............................. 4-37
Through Water
............................... 4-30
Wet Roads
.................................. 4-28
Winte
l- ...................................... 4-36
With
a Trailer ................................ 4-56
Drunken Driving
................................ 4-3
Dual Tire Operation
............................. 6-56
9-3
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