gear (Fig. 10). Do not fully tighten the fittings at this
time.
(7) Install the routing clamp with the bolt securing
the power steering fluid hoses to the rear of the cra-
dle crossmember (Fig. 11).
(8) Using a crowfoot wrench on a torque wrench,
tighten the power steering fluid hose tube nuts at the
gear to a torque of 31 N´m (275 in. lbs.).
(9) Install tie rod end into steering knuckle. Start
tie rod end to steering knuckle attaching nut onto
stud of tie rod end. While holding stud of tie rod end
stationary using a socket (Fig. 4), tighten tie rod end
to steering knuckle attaching nut. Then using a
crowfoot and socket (Fig. 13), tighten the tie rod end
attaching nut to a torque of 75 N´m (55 ft. lbs.).
(10) If the vehicle is equipped with All-Wheel-
Drive, install the power transfer unit (Refer to 21 -
TRANSMISSION/TRANSAXLE/POWER TRANSFER
UNIT - INSTALLATION).
CAUTION: Proper torque on the cradle reinforce-
ment to suspension cradle mounting bolts is very
important.
(11) Install the reinforcement on the front suspen-
sion cradle crossmember and install the bolts attach-
ing the reinforcement to the cradle crossmember
(Fig. 6). Tighten the M-14 size bolts to a torque of
163 N´m (120 ft. lbs.). Tighten the M-12 size bolts to
a torque of 108 N´m (80 ft. lbs.).
(12) Install the lower control arm rear bushing
retainer bolts through reinforcement on each side of
each lower control arm rear bushing. Tighten bolts to
a torque of 61 N´m (45 ft. lbs.).
(13) Install the two bolts and bushings attaching
the reinforcement and rear of cradle crossmember to
body of vehicle (Fig. 6). Tighten bolts to a torque of
163 N´m (120 ft. lbs.).
(14) If power steering cooler equipped, install the
previously disconnected power steering cooler hose on
the cooler. Install the clamp.
(15) If power steering cooler equipped, install the
power steering fluid cooler on the cradle crossmem-
ber reinforcement (Fig. 3). Install the mounting bolts
and tighten to 11 N´m (100 in. lbs.).
(16) Install the front tire and wheel assemblies on
vehicle. Install the wheel mounting lug nuts and
tighten to a torque to 135 N´m (100 ft. lbs.).
(17) Lower the vehicle to a level were the interior
of vehicle is accessible (keeping tires off the ground).
(18) With the wheels pointed approximately
STRAIGHT-AHEAD, align the intermediate shaft
with the steering column coupler. Assemble the steer-
ing column shaft coupler onto the steering gear inter-
mediate coupler (Fig. 2). Install steering column
coupler to intermediate shaft retaining pinch bolt.Tighten the pinch bolt nut to a torque of 28 N´m (250
in. lbs.).
(19) Remove the steering wheel holding tool.
(20) Perform the POWER STEERING PUMP INI-
TIAL OPERATION procedure to properly fill and
bleed the power steering system. (Refer to 19 -
STEERING/PUMP - STANDARD PROCEDURE)
(21) Inspect for leaks.
(22) Adjust front wheel toe (Refer to 2 - SUSPEN-
SION/WHEEL ALIGNMENT - STANDARD PROCE-
DURE).
SPECIAL TOOLS
POWER STEERING GEAR
OUTER TIE ROD
REMOVAL
(1) Loosen inner tie rod to outer tie rod jam nut
(Fig. 14).
(2) Remove nut attaching outer tie rod end to
steering knuckle (Fig. 15). The nut is to be removed
from tie rod end by holding tie rod end stud with a
11/32 socket while loosening and removing nut with a
wrench.
(3) Remove the tie rod end stud from steering
knuckle arm, using Remover, Special Tool C-3894±A
(Fig. 16).
(4) Remove outer tie rod end by un-threading it
from the inner tie rod.
INSTALLATION
NOTE: Before installing the outer tie rod, make sure
the jam nut is on inner tie rod (Fig. 14).
Puller C-3894A
Remover/Installer Steering Shaft Roll Pin 6831A
19 - 34 GEARRS
GEAR (Continued)
point must not affect alignment. Striker should go
straight into the latching mechanism.
(2) On vehicles with left sliding doors, check the
fuel door blocker striker entry into latch. Striker at
this point must not affect alignment.
(3) Check C-post and B-post for door to aperture
gaps and door to door gaps. All gaps should be 5 mm
1 mm.
(4) Check door for height using character lines as
a reference. Also check roof contour as a controlling
factor.
Using the procedures noted below, adjust the side
door in the order the individual steps are called out.
DOOR FLUSHNESS ADJUSTMENT
(1) Check sliding door flushness at the C-pillar
striker.
(2) If the sliding door is under or over flush,
remove striker assembly and move thread plate over
keeping one bolt in plate so it will not fall between
inner and outer panels.
(3) Adjust the C-pillar striker in or out until the
door is flush. Then, the on size hole can be elongated
in the direction required. This can be done by grind-
ing or filing the sheet metal and then painting raw
edge to prevent rusting.
(4) Check upper B-pillar flushness to A-pillar
cover.
(5) The sliding door upper hinge can only be
moved outboard by addinga1mmshim behind the
hinge mounting area once the too attachment bolts
are removed and reinstalled.
(6) Check flushness at upper C-pillar.
(7) If upper C-pillar flushness is out of specifica-
tion use a heavy rubber mallet on the door assembly
until door is in specifications.
DOOR GAP ADJUSTMENT - UP/DOWN
(1) Visually inspect the sliding door for fitting low
at the top of the door by checking the alignment of
the top contour of the door to the quarter panel.
(2) Fully open the sliding door.
(3) Verify that all center hinge bolts are tight.
(4) Adjust the rear of the sliding door up by turn-
ing the center hinge bolt clockwise (Fig. 14).
(5) Close the door and check the sliding door align-
ment.
(6) Adjust the front of the sliding door up by
adjusting lower hinge bolts.
(7) Open door half way and remove lower hinge
bolt access plug.
(8) Loosen bolts as necessary to move the front of
door up or down.
(9) Check the upper hinge for possible bind, adjust
as necessary.(10) Close the door and check the sliding door
alignment.
(11) Fully open door and apply thread lock nut
onto the center hinge bolt. Tighten nut until till it
butts up against the welded nut on the center hinge.
Tighten nut to 15 N´m (130 in. lbs.). It may be nec-
essary to hold the center hinge bolt to prevent it
from turning while tightening nut.
(12) Verify alignment, adjust as necessary.
DOOR GAP ADJUSTMENT - FORE/AFT
(1) Check height of sliding door at the B-post and
C-post to determine which area is contributing the
greatest to the incorrect gaps.
(2) If the sliding door is high at the C-post.
(a) Open the door to mid-point of travel.
(b) Mark outline of center hinge on sliding door
to assist in making adjustments.
(c) Loosen center hinge bolts (Fig. 14).
(d) Move hinge fore or aft to position the sliding
door into the correct location.
(e) Tighten center hinge bolts.
(f) Verify alignment, adjust as necessary.
(3) If the sliding door is low at the B-post;
(a) Remove access plug in the sliding door trim
panel.
(b) Open the door to mid-point of travel.
(c) Mark outline of lower roller arm bracket on
sliding door to assist in making adjustments.
(d) Loosen lower roller arm bracket bolts (Fig.
15).
(e) Move hinge upward to raise the door.
(f) Tighten lower roller arm bracket bolts.
(g) Verify alignment, adjust as necessary.
Fig. 14 SLIDING DOOR CENTER HINGE
1 - ADJUSTING BOLT
2 - WELD NUT
RSDOORS - SLIDING23-31
SLIDING DOOR (Continued)
²a rear window defogger on/off switch. A graphic
symbol shows when the defroster is on.
²a rotary knob for front fan speed selection can
override the automatic controls. LEDs surrounding
the knob show the current setting.
²a rotary knob for control of the rear system.
²a rotary knob for mode control can override the
automatic controls. LEDs surrounding the knob show
the current setting.
²computer logic which remembers the settings of
the controls when the ignition is turned off and
retains those settings after a restart. If the system is
off when the ignition is turned off it will be off when
the engine is restarted, etc.
²computer logic which provides variable air recir-
culation under high temperature and humidity condi-
tions. Because recirculation is generally accompanied
by increased fan noise, the proportion of recirculated
to outside air gradually approaches full recirculation
over a broad temperature range.
²computer logic which enables additional heat for
diesel equipped vehicles by using a supplemental
engine coolant heater.
REAR CONTROL PANEL
A rear control panel centrally mounted on the
headliner includes a VF digital display, a rocker con-
trol for temperature and rotary controls for adjust-
ment of mode and fan speed of the rear heat and air
conditioning unit by intermediate seat passengers.
OPERATION
OPERATION - HEATER AND AIR CONDITIONER
The heating and air conditioning systems pulls
outside (ambient) air through the cowl opening at the
base of the windshield and into the plenum chamber
above the heating, ventilation and air conditioning
(HVAC) housing, then through the evaporator coil.
Air flow can be directed either through or around the
heater core by adjusting the blend door with the tem-
perature control knob on the A/C-heater control
located on instrument panel. The air flow can then
be directed out from the panel, floor and defrost out-
lets in various combinations using the mode control
knob located on the A/C-heater control. Air flow
velocity can be adjusted with the blower speed selec-
tor located on the
NOTE: It is important to keep the air intake opening
clear of debris. Leaf particles and other debris that
is small enough to pass through the cowl opening
screen can accumulate within the HVAC housing.
The closed, warm, damp and dark environment cre-
ated within the housing is ideal for the growth of
certain molds, mildews and other fungi. Any accu-mulation of decaying plant matter provides an addi-
tional food source for fungal spores, which enter
the housing with the fresh intake-air. Excess debris,
as well as objectionable odors created by decaying
plant matter and growing fungi can be discharged
into the passenger compartment during heater-A/C
operation if the air intake opening is not kept clear
of debris.
The heater and air conditioning system is a blend-
air type system. In a blend-air system, a blend door
controls the amount of conditioned air that is allowed
to flow through, or around, the heater core. The tem-
perature control knob determines the discharge air
temperature by actuating an electric motor, which
operates the blend door. This allows an almost imme-
diate control of the output air temperature of the sys-
tem.
On all models, the outside air intake can be shut
off by pressing the Recirculation button on the A/C-
heater control. This will operate a electric actuated
recirculation air door that closes off the outside fresh
air intake and recirculates the air that is already
inside the vehicle.
The air conditioning compressor can be engaged in
any mode by pressing the snowflake, A/C on/off but-
ton. It can also be engaged by placing the mode con-
trol in the mix to defrost positions. This will remove
heat and humidity from the air before it is directed
through or around the heater core. The mode control
knob on the A/C-heater control is used to also direct
the conditioned air to the selected system outlets.
The mode control switch uses an electric motor to
control the mode doors.OPERATION - SINGLE ZONE
²The temperature control knob enables continu-
ously variable proportioning of the conditioned air.
²The mode control knob enables continuously
variable proportioning of air flow between modes and
has detents adjacent to each icon.
²The blower control provides four separate speeds
and an Off position.
²When the heater-A/C system is off, the HVAC
computer closes the recirculation door to prevent out-
side air from entering the passenger compartment.
²Interior air may be recirculated to speed up
heating or cooling in all modes except defrost and
mix by pressing the Recirculate button on the A/C-
heater control.
²To reduce humidity for rapid defogging, the A/C
compressor runs automatically in modes from ªmixº
to full defrost when outside temperatures are above
freezing.
²Air conditioning is available in any mode by
pressing the snowflake, A/C on/off button.
24 - 4 HEATING & AIR CONDITIONINGRS
HEATING & AIR CONDITIONING (Continued)
OPERATION - DUAL ZONE
²The two slide controls enable continuously vari-
able proportioning of the conditioned air.
²The mode control knob enables continuously
variable proportioning of air flow between modes and
has detents adjacent to each icon.
²The blower control provides four separate speeds
and an Off position.
²When the heater-A/C system is off, the HVAC
computer closes the recirculation door to prevent out-
side air from entering the passenger compartment.
²Interior air may be recirculated to speed up
heating or cooling in all modes except defrost and
mix by pressing the Recirculate button on the A/C-
heater control.
²To reduce humidity for rapid defogging, the A/C
compressor runs automatically in modes from ªmixº
to full defrost when outside temperatures are above
freezing.
²Air conditioning is available in any mode by
pressing the snowflake, A/C on/off button.
OPERATION - MANUAL THREE ZONE
FRONT CONTROL PANEL
²Primary control of the rear heater-A/C system is
on the instrument panel. This control allows the
driver to set the rear compartment fan speed, to turn
the rear heater-A/C system off, or to give control to
the intermediate seat occupants by switching to the
Rear position. When the rear heater-A/C system is
controlled from the instrument panel, rear air tem-
perature is based on the driver-side temperature con-
trol position, and the mode (floor or overhead air) is
based on the front control's mode position.
²The mode control knob enables continuously
variable proportioning of air flow between modes but
has detents adjacent to each icon.
²The blower control provides four separate speeds
and an Off position. When the heater-A/C system is
off, the HVAC computer closes the recirculation door
to prevent outside air from entering the passenger
compartment.
²Interior air may be recirculated to speed up
heating or cooling in all modes except defrost and
mix by pressing the Recirculate button on the control
panel.
²To reduce humidity for rapid defogging the A/C
compressor runs automatically in modes from ªmix'
to full defrost when outside temperatures are above
freezing.
²Air conditioning is available in any mode by
pressing the snowflake, A/C on/off, button.
REAR CONTROL PANEL
With the rear control active, temperature selection
dictates the air distribution mode (floor or overhead
air) of the rear unit: a cool temperature setting
directs flow to the overhead outlets and a warm tem-
perature setting to the floor.
OPERATION - THREE ZONE ATC
Comfort temperature or perceived temperature is
affected by air flow, sun levels on exposed skin, etc. The
air temperature may be higher or lower than the com-
fort temperature. Two infrared sensors in the instru-
ment panel center stack measure the temperature of
the occupants to determine their comfort level relative
to the selected comfort temperature. The integral
HVAC computer adjusts temperature and air flow rates
to maintain the customer-perceived comfort tempera-
ture. The air temperature in the passenger compart-
ment may be slightly higher or lower than the comfort
temperature at any time. For instance, on sunny sum-
mer days the air flow will probably be cooler than the
comfort temperature; on cold or cloudy days and at
night it will probably be slightly warmer. Infrared
Three-Zone Temperature Control provides side-to-side
and front-to-rear variations in comfort temperature set-
tings. The Infrared Three-Zone Automatic Temperature
Control fan provides a continuously variable air flow
rate to meet occupant comfort requirements.
FRONT CONTROL PANEL
²AUTO HI/LO± This system features two sets of
automatic control logic that allow either a rapid cool-
down rate or a somewhat slower cool-down rate with
less fan noise. HI-AUTO controls the system to reach
its assigned temperature quickly with a higher fan
speed. LO-AUTO controls the system to reach its
assigned temperature somewhat slower with less fan
noise. Both modes will automatically engage auto
recirculation.
²DE-FROST± The defrost function is active
when the rear window defogger function is active or
when the defog/defrost mode is selected.
²RECIRC± The RECIRC button will close the
air inlet door. If the system is in auto recirc (indica-
tor being displayed automatically), pressing the man-
ual recirc button will disable the auto recirc function
until one of the auto keys are pressed or the ignition
is cycled. If Auto HI/LO is pressed while manual
recirc is active, manual recirc will be deactivated.
²REAR WINDOW DEFOGGER± Pushing the
button sends a PCI bus message to the Intelligent
Power Module which controls the Rear Window
Defogger and side view mirror (if equipped) circuitry.
The defogger function will be active for 10 minutes
and can be turned off by a switch press. The defogger
will function while the control is in the ON mode.
RSHEATING & AIR CONDITIONING24-5
HEATING & AIR CONDITIONING (Continued)
²FAN/MODE± The Fan and Mode knobs have
17 manual selectable positions. Manually changing
either of the rotary knobs for mode or fan speed set-
tings makes control of that blowe motor manual. If
only one is changed manually, the other remains
under automatic control. Pressing the HI-AUTO/LO-
AUTO rocker switch restores full automatic control.
²REAR CONTROL± When the Rear System
control knob is moved to the OFF position, there will
be a delay of approximately 1 second before the sys-
tem actually turns off. This delay is to prevent an
undesired blower dropout if the knob is moved
through OFF to the other selections.
²BLOWER DELAY TIMER± The word DELAY
is displayed at start-up to signify that the system is
waiting so that cold air will not be blowing. This tells
the operator that it is unnecessary to turn the sys-
tem off, raise the temperature setting or turn the fan
speed setting down to prevent cold air from blowing.
A countdown in minutes and seconds until the engine
is warm enough to begin delivering heat to the pas-
sengers alternates with the DELAY message at 25
second intervals. This countdown is based on actual
measurement of the rate of engine coolant tempera-
ture change. During the delay time, mix mode is
selected and the fan operates at a low speed to keep
the windshield fog free.
REAR CONTROL PANEL
Primary control of the rear compartment unit is in
the instrument panel center stack. The rear unit con-
trol knob there allows the driver to turn the rear
unit off, allow control by the intermediate seat occu-
pants by switching to the REAR position, or provide
fully automatic control based on the temperature set-
ting shown on the front control display.
²REAR CONTROL± Selecting automatic control
of the rear unit at the instrument panel, illuminates
a Locked Padlock in the rear control panel display.
Selecting REAR activates the rear control panel and
the Padlock then appears unlocked.
²FAN KNOB± The rear fan control has Off and
AUTO positions and a range of manual speed set-
tings that override the AUTO setting.
²MODE KNOB± The mode control allows inter-
mediate seat occupants to manually override the
automatic mode and select any balance of air flow
between overhead and floor outlets from full over-
head to full floor.
²SET TEMP± The rear set temp control will
operate identical to the front controls. If the front
control rear set temp button is pressed simulta-
neously with the rear control head, then the front
control head press events shall have priority, i.e. if
the front user presses Rear Set Temp down and therear user presses Set Temp up, then the rear set
temp will decrease.
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - A/C COOL DOWN
TEST
The heater-A/C control module can perform an A/C
cool down test, which is a test performed during the
manufacturing process to confirm that the air condi-
tioning system is performing satisfactorily. This test
can also provide a quick confirmation of air condi-
tioning system performance to the service technician.
If the test is completed satisfactorily, no further ser-
vice is required. If the test is failed, proceed to the
A/C Performance Test to confirm the A/C system is
operating properly, or use a DRBIIItscan tool to
diagnose the A/C system control and distribution sys-
tems. Refer to the appropriate diagnostic informa-
tion.
MANUAL TEMPERATURE CONTROL
The front blower speed and rear blower speed (if
equipped with rear HVAC) must be set to High and
the evaporator temperature sensor must be greater
than 13É C (55É F) or the test will fail immediately.
The test is activated by depressing the A/C and Rear
Wipe/Wash buttons simultaneously and holding them
depressed for no less than five seconds. The Rear
Wipe/Wash and A/C LEDs will blink on and off until
the test is complete. If the LEDs stop blinking before
two minutes, then the cool down test has been com-
pleted successfully. If the two minutes expire without
the expansion valve temperature reaching -6É C (20É
F) less than the outside air temperature, then the
cool down test has been failed and further A/C sys-
tem diagnosis is required. If the test is failed, the
LEDs will continue to blink until the vehicle has
been driven for greater than 1.6 km (8 miles).
AUTOMATIC TEMPERATURE CONTROL
The ambient air temperature in the room where
the vehicle will be tested must be a minimum of 21É
C (70ÉF) for this test. The test is activated by
depressing the A/C and PWR buttons simultaneously
and holding them depressed for no less than four sec-
onds. The snowflake icon and the DELAY text in the
ATC display will blink on and off alternately until
the test is complete. If the snowflake icon and the
DELAY text stop blinking before two minutes, then
the cool down test has been completed successfully. If
the two minutes expire without the evaporator tem-
perature reaching -6É C (20É F) less than the evapo-
rator initial temperature, then the cool down test has
been failed and further A/C system diagnosis is
24 - 6 HEATING & AIR CONDITIONINGRS
HEATING & AIR CONDITIONING (Continued)
required. If the test is failed, the snowflake icon and
the DELAY text will continue to blink across ignition
cycles until the vehicle has been driven for greater
than 1.6 km (8 miles).
DIAGNOSIS AND TESTING - A/C
PERFORMANCE TEST
The A/C system is designed to remove heat and
humidity from the air entering the passenger com-
partment. The evaporator, located in the HVAC hous-
ing, is cooled to temperatures near the freezing point.
As warm damp air passes over the fins in the A/C
evaporator, moisture in the air condenses to water,
dehumidifying the air. Condensation on the evapora-
tor fins reduces the evaporators ability to absorb
heat. During periods of high heat and humidity, an
A/C system will be less effective. With the instru-
ment control set to recirculation mode, only air from
the passenger compartment passes through the A/C
evaporator. As the passenger compartment air dehu-
midifies, A/C performance levels rise.
Humidity has an important bearing on the temper-
ature of the air delivered to the interior of the vehi-
cle. It is important to understand the effect that
humidity has on the performance of the A/C system.
When humidity is high, the A/C evaporator has to
perform a double duty. It must lower the air temper-
ature, and it must lower the temperature of the
moisture in the air that condenses on the evaporator
fins. Condensing the moisture in the air transfers
heat energy into the evaporator fins and tubing. This
reduces the amount of heat the A/C evaporator can
absorb from the air. High humidity greatly reduces
the ability of the A/C evaporator to lower the temper-
ature of the air.
However, evaporator capacity used to reduce the
amount of moisture in the air is not wasted. Wring-
ing some of the moisture out of the air entering the
vehicle adds to the comfort of the passengers.
Although, an owner may expect too much from their
A/C system on humid days. A performance test is the
best way to determine whether the system is per-
forming up to design standards. This test also pro-
vides valuable clues as to the possible cause of
trouble with the A/C system. The ambient air tem-perature in the location where the vehicle will be
tested must be a minimum of 21É C (70É F) for this
test.
PERFORMANCE TEST PROCEDURE
WARNING: REFER TO THE APPLICABLE WARN-
INGS AND CAUTIONS FOR THIS SYSTEM BEFORE
PERFORMING THE FOLLOWING OPERATION (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMBING -
FRONT - WARNING - A/C PLUMBING) and (Refer to
24 - HEATING & AIR CONDITIONING/PLUMBING -
FRONT - CAUTION - A/C PLUMBING).
NOTE: When connecting the service equipment
coupling to the line fitting, verify that the valve of
the coupling is fully closed. This will reduce the
amount of effort required to make the connection.
(1) Connect a tachometer and a manifold gauge
set.
(2) Set the mode control to the Recirculation Mode
position, the temperature control to the full cool posi-
tion and the blower to the highest speed position.
(3) Start the engine and hold at 1,000 rpm with
the A/C compressor clutch engaged.
(4) The engine should be warmed up to operating
temperature with the doors closed and windows
open.
(5) Insert a thermometer in the driver's side center
panel A/C-heater outlet and operate the engine for
five minutes.
(6) If the compressor clutch does not engage, pro-
ceed with diagnosis of the compressor clutch coil.
(Refer to 24 - HEATING & AIR CONDITIONING/
CONTROLS - FRONT/COMPRESSOR CLUTCH
COIL - DIAGNOSIS AND TESTING).
(7) With the A/C compressor clutch engaged, com-
pare the air temperature at the center panel outlet
and the compressor discharge pressure to the A/C
Performance Temperature and Pressure chart. The
compressor clutch may cycle, depending upon the
ambient temperature and humidity. If the clutch
cycles, use the readings obtained before the clutch
disengaged.
RSHEATING & AIR CONDITIONING24-7
HEATING & AIR CONDITIONING (Continued)
Condition Possible Causes Correction
The low side pressure is too
low, and the high side
pressure is too high.1. Restricted refrigerant flow
through the refrigerant lines.1. See Liquid Line, Suction Line and Discharge
Line in this group. Inspect the refrigerant lines for
kinks, tight bends or improper routing. Correct
the routing or replace the refrigerant line, if
required.
2. Restricted refrigerant flow
through the A/C expansion
valve.2. See A/C Expansion Valve in this group.
Replace the valve, if required.
3. Restricted refrigerant flow
through the A/C condenser.3. See A/C Condenser in this group. Replace the
restricted condenser, if required.
DIAGNOSIS AND TESTING - HEATER
PERFORMANCE TEST
WARNING: REVIEW SAFETY PRECAUTIONS AND
WARNINGS IN THIS GROUP BEFORE PERFORMING
THIS PROCEDURE (Refer to 24 - HEATING & AIR
CONDITIONING/PLUMBING - WARNING).
Check the coolant level, drive belt tension, radiator
air flow and fan operation. Start engine and allow to
warm up to normal operating temperature.
WARNING: DO NOT REMOVE RADIATOR CAP
WHEN ENGINE IS HOT, PERSONAL INJURY CAN
RESULT.
If vehicle has been run recently, wait 15 minutes
before removing the radiator cap. Place a rag overthe cap and turn it to the first safety stop. Allow
pressure to escape through the overflow tube. When
the system pressure stabilizes, remove the cap com-
pletely.
MAXIMUM HEATER OUTPUT: TEST AND ACTION
Engine coolant is provided to the heater system by
two heater hoses. With the engine idling at normal
operating temperature, set the temperature control
to maximum heat, the mode control to the floor posi-
tion, and the blower in the highest speed position.
Using a test thermometer, check the temperature of
the air being discharged from the floor outlets. Com-
pare the test thermometer reading to the Tempera-
ture Reference chart.
TEMPERATURE REFERENCE
Ambient Temperature Minimum Floor Outlet Temperature
Celsius Fahrenheit Celsius Fahrenheit
15.5É 60É 62.2É 144É
21.1É 70É 63.8É 147É
26.6É 80É 65.5É 150É
32.2É 90É 67.2É 153É
If the floor outlet air temperature is insufficient,
check that the cooling system is operating to specifi-
cations (Refer to 7 - COOLING/ENGINE - DIAGNO-
SIS AND TESTING). Both heater hoses should be
HOT to the touch (the coolant return hose should be
slightly cooler than the supply hose). If the coolant
return hose is much cooler than the supply hose,
locate and repair the engine coolant flow obstruction
in heater system.OBSTRUCTED COOLANT FLOW Possible locations or causes
of obstructed coolant flow are as follows:
²Pinched or kinked heater hoses.
²Improper heater hose routing.
²Plugged heater hoses or supply and return ports
at the cooling system connections.
²Plugged heater core.
If proper coolant flow through the cooling system is
verified, and heater outlet air temperature is insuffi-
cient, a mechanical problem may exist.
24 - 10 HEATING & AIR CONDITIONINGRS
HEATING & AIR CONDITIONING (Continued)
CONTROLS - REAR
TABLE OF CONTENTS
page page
A/C-HEATER CONTROL
DESCRIPTION.........................34
OPERATION...........................34
REMOVAL.............................34
INSTALLATION.........................35
BLEND DOOR ACTUATOR
DESCRIPTION.........................35
OPERATION...........................35
REMOVAL.............................36
INSTALLATION.........................36
BLOWER MOTOR RELAY
DESCRIPTION.........................37
OPERATION...........................37
REMOVAL.............................38
INSTALLATION.........................38
BLOWER MOTOR RESISTOR
DESCRIPTION.........................38OPERATION...........................38
DIAGNOSIS AND TESTING - REAR BLOWER
MOTOR RESISTOR BLOCK..............38
REMOVAL.............................39
INSTALLATION.........................39
MODE DOOR ACTUATOR - REAR
DESCRIPTION.........................39
OPERATION...........................40
REMOVAL.............................40
INSTALLATION.........................40
POWER MODULE - REAR BLOWER MOTOR
DESCRIPTION.........................41
OPERATION...........................41
REMOVAL.............................41
INSTALLATION.........................42
A/C-HEATER CONTROL
DESCRIPTION
The rear heater-A/C system is controlled by rotary-
type blower motor and temperature controls, cen-
trally mounted in the headliner. The rear A/C-heater
control allows selection of three blower motor speeds
and an Off position when the center knob on the
front A/C-heater control is set to the Rear position,
otherwise the front unit controls both front and rear
heater-A/C operation.
OPERATION
With the rear A/C-heater control active, tempera-
ture selection dictates the air distribution mode (floor
or overhead air) of the rear unit. A cool temperature
setting directs flow to the overhead outlets and a
warm temperature setting to the floor. Refer to Body
Diagnostic Procedures for further diagnostic informa-
tion.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Using a trim stick or another suitable wide flat
bladed tool, gently pry the top edge of the rear A/C-
heater control bezel away from the headliner far
enough to release the two snap clip retainers (Fig. 1).(3) Pull the rear A/C-heater control rearward far
enough to access the headliner wire harness connec-
tor on the back of the control.
(4) Disconnect the wire harness connector from the
rear A/C-heater control.
(5) Remove the rear A/C-heater control from the
headliner.
Fig. 1 Rear A/C-Heater Control
1 - TRIM STICK
2 - BEZEL
3 - REAR A/C-HEATER CONTROL
4 - HEADLINER
24 - 34 CONTROLS - REARRS