ECU DODGE RAM 2001 Service Repair Manual

With the blower motor switch in the lowest speed
position, the ground path for the motor is applied
through all of the resistor wires. Each higher speed
selected with the blower motor switch applies the
blower motor ground path through fewer of the resis-
tor wires, increasing the blower motor speed. When
the blower motor switch is in the highest speed posi-
tion, the blower motor resistor is bypassed and the
blower motor receives a direct path to ground.
The blower motor resistor cannot be repaired and,
if faulty or damaged, it must be replaced.
DIAGNOSIS AND TESTING - BLOWER MOTOR
RESISTOR BLOCK
For circuit descriptions and diagrams, (Refer to
Appropriate Wiring Information).
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Disconnect and isolate the battery negative
cable.
(2) Unplug the wire harness connector from the
blower motor resistor.
(3) Check for continuity between each of the
blower motor switch input terminals of the resistor
and the resistor output terminal. In each case there
should be continuity. If OK, repair the wire harness
circuits between the blower motor switch and the
blower motor resistor or blower motor as required. If
not OK, replace the faulty blower motor resistor.
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAGSYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Disconnect and isolate the battery negative
cable.
(2) Reach under the passenger side end of the
HVAC housing and unplug the wire harness connec-
tor from the blower motor resistor.
(3) Remove the screws that secure the blower
motor resistor to the HVAC housing.
(4) Remove the blower motor resistor from the
HVAC housing (Fig. 23).
INSTALLATION
(1) Install the blower motor resistor into the HVAC
housing and secure it with the mounting screws.
Tighten the mounting screws to 2.2 N´m (20 in. lbs.).
(2) Plug the wire harness connector into the
blower motor resistor.
(3) Connect the battery negative cable.
BLOWER MOTOR SWITCH
DESCRIPTION
The heater-only or a/c heater blower motor is con-
trolled by a four position rotary-type blower motor
switch, mounted in the HVAC control panel. The
switch allows the selection of one of four blower
Fig. 23 BLOWER MOTOR/RESISTOR
1 - BLOWER MOTOR
2 - BLOWER MOTOR RESISTOR
24 - 24 CONTROLSBR/BE
BLOWER MOTOR RESISTOR BLOCK (Continued)

motor speeds, but can only be turned off by selecting
the Off position with the heater-only or a/c heater
control switch knob.
OPERATION
The blower motor switch directs the blower motor
ground path through the mode control switch to the
blower motor resistor, or directly to ground, as
required to achieve the selected blower motor speed.
The blower motor switch cannot be repaired and, if
faulty or damaged, the entire heater-only or a/c
heater control unit must be replaced. The blower
motor switch knob is serviced separately.
DIAGNOSIS AND TESTING - BLOWER MOTOR
SWITCH
For circuit descriptions and diagrams, (Refer to
Appropriate Wiring Information).
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Check for battery voltage at the fuse in the
Power Distribution Center (PDC). If OK, go to Step
2. If not OK, repair the shorted circuit or component
as required and replace the faulty fuse.
(2) Turn the ignition switch to the Off position.
Disconnect and isolate the battery negative cable.
Remove the a/c heater control from the instrument
panel. (Refer to 24 - HEATING & AIR CONDITION-
ING/CONTROLS/A/C HEATER CONTROL -
REMOVAL) Check for continuity between the ground
circuit cavity of the a/c heater control wire harness
connector and a good ground. There should be conti-
nuity. If OK, go to Step 3. If not OK, repair the open
circuit to ground as required.
(3) With the a/c heater control wire harness con-
nector unplugged, place the a/c heater mode control
switch knob in any position except the Off position.
Check for continuity between the ground circuit ter-
minal and each of the blower motor driver circuit ter-
minals of the a/c heater control as you move the
blower motor switch knob to each of the four speed
positions. There should be continuity at each drivercircuit terminal in only one blower motor switch
speed position. If OK, test and repair the blower
driver circuits between the a/c heater control connec-
tor and the blower motor resistor as required. If not
OK, replace the faulty a/c heater control unit.
REMOVAL
The blower motor switch cannot be repaired and, if
faulty or damaged, the entire heater-only or a/c
heater control unit must be replaced. (Refer to 24 -
HEATING & AIR CONDITIONING/CONTROLS/A/C
HEATER CONTROL - REMOVAL) The blower motor
switch knob is serviced separately.
BLEND DOOR ACTUATOR
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Turn the ignition switch to the run position.
(2) Locate the temperature control knob in the mid
(12 o'clock) position.
(3) Turn the ignition switch to the off position.
(4) Disconnect and isolate the battery negative
cable.
(5) Remove the instrument panel from the vehicle.
Refer to Instrument Panel System for the procedures.
(6) Remove the HVAC housing from the vehicle.
(Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION/HVAC HOUSING - REMOVAL)
(7) Unplug the wire harness connector from the
blend door actuator (Fig. 24).
(8) Remove the two mounting screws which secure
the actuator to the housing.
(9) Slide the blend door actuator off the blend door
shaft.
NOTE: A black plastic coupler may be attached to
the blend door shaft. Remove the coupler and
inspect for damage. Reinstall if there is no damage
found.
BR/BECONTROLS 24 - 25
BLOWER MOTOR SWITCH (Continued)

INSTALLATION
NOTE: Before installing the blend door actuator, be
certain that the blend door is not binding and is
capable of full travel in both directions.
(1) Align the actuator with the blend door shaft
and rotate the actuator to align it to the mounting
bosses on the HVAC housing.
(2) Align and install the actuator screws. Tighten
the mounting screws to 2.2 N´m (20 in. lbs.).
(3) Plug in the wire harness connector to the blend
door actuator.
(4) Install the HVAC housing in the vehicle. (Refer
to 24 - HEATING & AIR CONDITIONING/DISTRI-
BUTION/HVAC HOUSING - INSTALLATION)
(5) Install the instrument panel in the vehicle.
Refer to Instrument Panel System for the procedures.
(6) Make sure the Temperature Control Knob is in
the mid (12 o'clock) position to allow the actuator to
automatically position itself in the mid position and
come to a complete stop when powered up.
(7) Connect the battery negative cable.
MODE DOOR ACTUATOR
REMOVAL - HEAT/DEFROST DOOR ACTUATOR
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the HVAC housing from the vehicle
and place it on a work bench. (Refer to 24 - HEAT-
ING & AIR CONDITIONING/DISTRIBUTION/HVAC
HOUSING - REMOVAL)
(3) Unplug the two vacuum harness connectors
from the heat/defrost door actuator (Fig. 25).
(4) Using a trim stick or another suitable wide
flat-bladed tool, gently pry the heat/defrost door
crank arm off the heat/defrost door pivot.
(5) Remove the two screws that secure the heat/de-
frost door actuator to the HVAC housing.
(6) Remove the heat/defrost door actuator from the
HVAC housing.
Fig. 24 BLEND DOOR ACTUATOR REMOVE/
INSTALL
1 - DUCT
2 - MOUNTING SCREWS
3 - UNIT HOUSING
4 - HARNESS AND CONNECTOR
5 - BLEND DOOR ACTUATOR
Fig. 25 HEAT/DEFROST DOOR ACTUATOR
1 - VACUUM LINE
2 - DOOR PIVOT CONNECTION
3 - HEAT/DEFROST DOOR ACTUATOR
24 - 26 CONTROLSBR/BE
BLEND DOOR ACTUATOR (Continued)

REMOVAL - PANEL/DEFROST DOOR
ACTUATOR
WARNING: ON VEHICLES EQUIPPED WITH AIRBAGS,
DISABLE THE AIRBAG SYSTEM BEFORE ATTEMPT-
ING ANY STEERING WHEEL, STEERING COLUMN, OR
INSTRUMENT PANEL COMPONENT DIAGNOSIS OR
SERVICE. DISCONNECT AND ISOLATE THE BATTERY
NEGATIVE (GROUND) CABLE, THEN WAIT TWO MIN-
UTES FOR THE AIRBAG SYSTEM CAPACITOR TO DIS-
CHARGE BEFORE PERFORMING FURTHER
DIAGNOSIS OR SERVICE. THIS IS THE ONLY SURE
WAY TO DISABLE THE AIRBAG SYSTEM. FAILURE TO
TAKE THE PROPER PRECAUTIONS COULD RESULT
IN AN ACCIDENTAL AIRBAG DEPLOYMENT AND POS-
SIBLE PERSONAL INJURY.
(1)Disconnect and isolate the battery negative cable.
(2) Remove the instrument panel assembly from
the vehicle. Refer to Instrument Panel System for the
procedures.
(3) Unplug the vacuum harness connector from the
panel/defrost door actuator (Fig. 26).
(4) Using a trim stick or another suitable wide
flat-bladed tool, gently pry the panel/defrost door
crank arm off the panel/defrost door pivot.
(5) Remove the two screws that secure the panel/
defrost door actuator to the HVAC housing.
(6) Remove the panel/defrost door actuator from
the HVAC housing.
INSTALLATION - HEAT/DEFROST DOOR
ACTUATOR
NOTE: Before installing the heat/defrost door actuator,
be certain that the heat/defrost door is not binding.
(1) Install the heat/defrost door actuator from the
HVAC housing. Tighten the actuator mounting
screws to 2.2 N´m (20 in. lbs.).
(2) Carefully snap the heat/defrost door crank arm
on the heat/defrost door pivot.
(3) Plug in the two vacuum harness connectors to
the heat/defrost door actuator.
(4) Install the HVAC housing in the vehicle. (Refer
to 24 - HEATING & AIR CONDITIONING/DISTRI-
BUTION/HVAC HOUSING - INSTALLATION)
(5) Connect the battery negative cable.
INSTALLATION - PANEL/DEFROST DOOR
ACTUATOR
NOTE: Before installing the panel/defrost door actuator,
be certain that the panel/defrost door is not binding.
(1) Install the panel/defrost door actuator on the
HVAC housing. Tighten the mounting screws to 2.2
N´m (20 in. lbs.).
(2) Carefully snap the panel/defrost door crank
arm on the panel/defrost door pivot.
(3) Plug the vacuum harness connector to the pan-
el/defrost door actuator.
(4) Install the instrument panel assembly in the
vehicle. Refer to Instrument Panel System for the
procedures.
(5) Connect the battery negative cable.
RECIRCULATION DOOR
ACTUATOR
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
Fig. 26 PANEL/DEFROST DOOR ACTUATOR
1 - VACUUM LINE
2 - PANEL/DEFROST ACTUATOR
3 - SHAFT RETAINER
BR/BECONTROLS 24 - 27
MODE DOOR ACTUATOR (Continued)

(1) Disconnect and isolate the battery negative
cable.
(2) Remove the glove box from the instrument
panel. Refer to Glove Box in Instrument Panel Sys-
tem for the procedures.
(3) Reach through the glove box opening to access
and unplug the vacuum harness connector from the
recirculation door actuator (Fig. 27).
(4) Loosen the two nuts that secure the recircula-
tion door actuator to the mounting bracket on the
HVAC housing.
(5) Slide the two actuator mounting studs out of
the slots in the actuator mounting bracket.
(6) Pull the recirculation door actuator downward
far enough to access the clip that retains the actua-
tor link to the recirculation door lever.
(7) Unsnap the clip from the recirculation door
actuator link and disengage the link from the recir-
culation door lever.
(8) Remove the recirculation door actuator from
the HVAC housing.INSTALLATION
NOTE: When reinstalling the recirculation door
actuator, insert a screwdriver or another suitable
tool through the recirculation air intake grille to
prop the recirculation air door up in the open posi-
tion far enough to access the recirculation air door
lever through the instrument panel glove box open-
ing.
NOTE: Before installing the blend door actuator, be
certain that the blend door is not binding.
(1) Snap the clip on the recirculation door actuator
link to engage the link to the recirculation door lever.
(2) Slide the two actuator mounting studs into the
slots in the actuator mounting bracket.
(3) Install the two nuts that secure the recircula-
tion door actuator to the mounting bracket on the
HVAC housing. Tighten the mounting nuts until the
recirculation air door actuator is seated to the
mounting bracket.
(4) Plug in the vacuum harness connector to the
recirculation door actuator.
(5) Install the glove box in the instrument panel.
Refer to Glove Box in Instrument Panel System for
the procedures.
(6) Connect the battery negative cable.
VACUUM CHECK VALVE
DESCRIPTION
On models with a gasoline engine, a vacuum check
valve is installed in the accessory vacuum supply line
near the vacuum tap on the right side of the engine
intake manifold. On models with a diesel engine, a
vacuum check valve is installed on the engine vac-
uum pump. The vacuum check valve is designed to
allow vacuum to flow in only one direction through
the accessory vacuum supply circuits.
OPERATION
The use of a vacuum check valve helps to maintain
the system vacuum needed to retain the selected
HVAC mode and vehicle speed control settings. On
gasoline engine models, it prevents the engine from
bleeding down system vacuum through the intake
manifold during extended heavy engine load (low
engine vacuum) operation. On diesel engine models,
it prevents oil from contaminating the vacuum sup-
ply system by maintaining vacuum in the pump after
the engine is shut-off.
On gasoline engine models, a second vacuum check
valve is installed in the accessory vacuum supply line
at the tee fitting near the dash panel in the engine
Fig. 27 RECIRCULATION DOOR ACTUATOR
1 - DOOR SHAFT RETAINER
2 - RECIRCULATION DOOR
3 - ROD CLIP
4 - BLOWER MOTOR ELECTRICAL CONNECTOR
5 - RECIRCULATION DOOR ACTUATOR
6 - BLOWER MOTOR
7 - VACUUM LINE
24 - 28 CONTROLSBR/BE
RECIRCULATION DOOR ACTUATOR (Continued)

REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the wiper arms from the wiper pivots.
Refer to Wipers/Washers for the procedures.
(3) Remove the weatherstrip along the front edge
of the cowl plenum cover/grille panel and the cowl
plenum panel (Fig. 30).
(4) Remove the plastic screws that secure the cowl
plenum cover/grille panel to the studs on the cowl top
panel near the base of the windshield (Fig. 31).(5) Lift the cowl plenum cover/grille panel from the
cowl top far enough to access the vacuum reservoir
near the right end of the cowl plenum.
(6) Disconnect the vacuum supply hose from the
vacuum reservoir, which is secured to the dash panel
near the right end of the cowl plenum (Fig. 32).
(7) Remove the two nuts that secure the reservoir
to the studs on the dash panel near the right end of
the cowl plenum.
(8) Remove the vacuum reservoir from the dash
panel studs.
INSTALLATION
(1) Install the vacuum reservoir on the dash panel
studs. Tighten the mounting nuts to 2.8 N´m (25 in.
lbs.).
(2) Connect the vacuum supply hose to the vac-
uum reservoir.
(3) Install the plastic screws that secure the cowl
plenum cover/grille panel to the studs on the cowl top
panel.
(4) Install the weatherstrip along the front edge of
the cowl plenum cover/grille panel and the cowl ple-
num panel.
(5) Install the wiper arms on the wiper pivots.
Refer to Wipers/Washers for the procedures.
(6) Connect the battery negative cable.
Fig. 30 COWL PLENUM COVER/GRILLE PANEL
WEATHERSTRIP
1 - COWL GRILLE
2 - WEATHERSTRIP
Fig. 31 COWL PLENUM PLASTIC SCREWS
REMOVAL
1 - PLASTIC SCREW ANCHOR
2 - COWL GRILLE
Fig. 32 VACUUM RESERVOIR REMOVE/INSTALL
1 - COWL PLENUM
2 - VACUUM RESERVOIR
24 - 30 CONTROLSBR/BE
VACUUM RESERVOIR (Continued)

DIAGNOSIS AND TESTING - BLOWER MOTOR
WARNING: ON VEHICLES EQUIPPED WITH AIRBAGS,
DISABLE THE AIRBAG SYSTEM BEFORE ATTEMPT-
ING ANY STEERING WHEEL, STEERING COLUMN, OR
INSTRUMENT PANEL COMPONENT DIAGNOSIS OR
SERVICE. DISCONNECT AND ISOLATE THE BATTERY
NEGATIVE (GROUND) CABLE, THEN WAIT TWO MIN-
UTES FOR THE AIRBAG SYSTEM CAPACITOR TO DIS-
CHARGE BEFORE PERFORMING FURTHER
DIAGNOSIS OR SERVICE. THIS IS THE ONLY SURE
WAY TO DISABLE THE AIRBAG SYSTEM. FAILURE TO
TAKE THE PROPER PRECAUTIONS COULD RESULT
IN AN ACCIDENTAL AIRBAG DEPLOYMENT AND POS-
SIBLE PERSONAL INJURY.
For circuit descriptions and diagrams, (Refer to
Appropriate Wiring Information). Possible causes of
an inoperative blower motor include:
²Faulty fuse
²Faulty blower motor circuit wiring or wire har-
ness connectors
²Faulty blower motor resistor
²Faulty blower motor relay
²Faulty blower motor switch
²Faulty a/c heater mode control switch
²Faulty blower motor.
Possible causes of the blower motor not operating
in all speeds include:
²Faulty fuse
²Faulty blower motor switch
²Faulty blower motor resistor
²Faulty blower motor relay
²Faulty blower motor circuit wiring or wire har-
ness connectors.
VIBRATION
Possible causes of blower motor vibration include:
²Improper blower motor mounting
²Improper blower wheel mounting
²Blower wheel out of balance or deformed
²Blower motor faulty.
NOISE
To verify that the blower is the source of the noise,
unplug the blower motor wire harness connector and
operate the HVAC system. If the noise goes away,
possible causes include:
²Foreign material in the HVAC housing
²Improper blower motor mounting
²Improper blower wheel mounting
²Blower motor faulty.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.(2) Disconnect the blower motor cooling tube from
the nipple on the blower motor housing (Fig. 3).
(3) Disengage the blower motor wire harness from
the wire harness retainer.
(4) Unplug the blower motor wire harness connec-
tor from the HVAC housing wire harness.
(5) Remove the three screws that secure the
blower motor and blower wheel assembly to the
HVAC housing.
(6) Lower the blower motor and wheel assembly,
and cover, from the HVAC housing.
(7)
Remove the blower wheel retainer clip and
remove the wheel from the blower motor shaft (Fig. 4).
INSTALLATION
(1) If installing the blower motor wheel only, press
the blower wheel hub onto the blower motor shaft.
Be sure the flat on the blower motor shaft is indexed
to the flat on the inside of the blower wheel hub.
(2) Install the retainer clip over the blower wheel
hub. The ears of the retainer clip must be indexed
over the flats on the blower motor shaft and blower
wheel hub.
(3) Be certain that the blower motor seal is
installed on the blower motor housing (Fig. 5).
(4) Install the blower motor and wheel assembly,
and cover in the HVAC housing with three mounting
screws. Tighten the mounting screws to 2.2 N´m (20
in. lbs.).
Fig. 3 BLOWER MOTOR REMOVE/INSTALL
1 - BLOWER MOTOR HOUSING
2 - COOLING TUBE
3 - ELECTRICAL CONNECTOR
BR/BEDISTRIBUTION 24 - 33
BLOWER MOTOR (Continued)

(5) Plug the blower motor wire harness connector
into the HVAC housing wire harness.
(6) Install the blower motor wire harness into the
wire harness retainer.
(7) Connect the blower motor cooling tube to the
nipple on the blower motor housing.
(8) Connect the battery negative cable.
DEFROSTER DUCTS
REMOVAL - DEFROSTER AND DEMISTER
DUCTS
The defroster duct and the main demister duct are
a single molded plastic unit. The defroster outletgrilles are heat-staked to the defroster outlets and
cannot be serviced separately. The demister tubes on
each end of the main demister duct are only serviced
in the instrument panel assembly.
(1) Remove the instrument panel top cover from
the instrument panel. Refer to Instrument System
for the procedures.
(2) Remove the screws that secure the defroster
and demister ducts to the instrument panel brackets
(Fig. 6).
Fig. 5 BLOWER MOTOR SEAL
1 - BLOWER MOTOR SEAL
Fig. 6 DEFROSTER AND DEMISTER DUCT
1 - DEMISTER TUBE
2 - INSTRUMENT PANEL TOP COVER3 - BRACKETS
4 - DEFROSTER AND DEMISTER DUCT
Fig. 4 BLOWER MOTOR WHEEL REMOVE/INSTALL
1 - BLOWER MOTOR WHEEL
2 - RETAINER CLIP
24 - 34 DISTRIBUTIONBR/BE
BLOWER MOTOR (Continued)

(3) Disengage the demister tubes from each end of
the main demister duct.
(4) Remove the defroster and demister duct unit
from the instrument panel.
REMOVAL - DEFROSTER AND DEMISTER
DUCT ADAPTER
(1) Roll the instrument panel assembly down, but
do not remove it from the vehicle. Refer to Instru-
ment Panel System for the procedures.
(2)
Using a trim stick or another suitable wide flat-
bladed tool, gently pry at the perimeter edges of the
defroster and demister duct adapter to release the snap
features from the top of the HVAC housing (Fig. 7).
(3) Remove the defroster and demister duct
adapter from the top of the HVAC housing.
INSTALLATION - DEFROSTER AND DEMISTER
DUCTS
(1) Place the defroster and demister duct unit in
position.
(2) Engage the demister tubes with each end of
the main demister duct.
(3) Install the screws that secure the defroster and
demister ducts to the instrument panel brackets.
Tighten the mounting screws to 2.2 N´m (20 in. lbs.).
(4) Install the instrument panel top cover on the
instrument panel. Refer to Instrument System for
the procedures.
INSTALLATION - DEFROSTER AND DEMISTER
DUCT ADAPTER
(1) Snap the defroster and demister duct adapter
from the top of the HVAC housing.
(2) Roll the instrument panel assembly up, and
fasten it properly to the vehicle. Refer to Instrument
Panel System for the procedures.
HVAC HOUSING
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIRBAGS,
DISABLE THE AIRBAG SYSTEM BEFORE ATTEMPT-
ING ANY STEERING WHEEL, STEERING COLUMN, OR
INSTRUMENT PANEL COMPONENT DIAGNOSIS OR
SERVICE. DISCONNECT AND ISOLATE THE BATTERY
NEGATIVE (GROUND) CABLE, THEN WAIT TWO MIN-
UTES FOR THE AIRBAG SYSTEM CAPACITOR TO DIS-
CHARGE BEFORE PERFORMING FURTHER
DIAGNOSIS OR SERVICE. THIS IS THE ONLY SURE
WAY TO DISABLE THE AIRBAG SYSTEM. FAILURE TO
TAKE THE PROPER PRECAUTIONS COULD RESULT
IN AN ACCIDENTAL AIRBAG DEPLOYMENT AND POS-
SIBLE PERSONAL INJURY.
WARNING: IF THE VEHICLE IS EQUIPPED WITH AIR
CONDITIONING, REVIEW THE WARNINGS AND
CAUTIONS IN PLUMBING BEFORE PERFORMING
THE FOLLOWING OPERATION. (Refer to 24 - HEAT-
ING & AIR CONDITIONING/PLUMBING - WARNING)
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - CAUTION)
The HVAC housing assembly must be removed
from the vehicle and disassembled for service access
of the heater core, a/c evaporator, and each of the
various mode control doors.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the instrument panel from the vehicle.
Refer to Instrument Panel System for the procedures.
(3) If the vehicle is not equipped with air condi-
tioning, go to Step 6. If the vehicle is equipped with
air conditioning, recover the refrigerant from the sys-
tem. (Refer to 24 - HEATING & AIR CONDITION-
ING/PLUMBING - STANDARD PROCEDURE -
REFRIGERANT RECOVERY)
(4) Disconnect the liquid line refrigerant line fit-
ting from the evaporator inlet tube. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE - A/C LINE COUPLERS)
Install plugs in, or tape over all of the opened refrig-
erant line fittings.
Fig. 7 DEFROSTER AND DEMISTER DUCT
ADAPTER REMOVE/INSTALL
1 - DEFROSTER AND DEMISTER DUCT ADAPTER
2 - HVAC HOUSING
BR/BEDISTRIBUTION 24 - 35
DEFROSTER DUCTS (Continued)

(5) Remove the accumulator. (Refer to 24 - HEAT-
ING & AIR CONDITIONING/PLUMBING/ACCU-
MULATOR - REMOVAL) Install plugs in, or tape
over all of the opened refrigerant line fittings.
(6) Drain the engine cooling system. Refer to Cool-
ing for the procedures.
(7)
Disconnect the heater hoses from the heater core
tubes. Refer to Cooling for the procedures. Install plugs
in, or tape over the opened heater core tubes.
(8) Remove the Powertrain Control Module (PCM)
from the dash panel and set it aside, but do not
unplug the PCM wire harness connectors. Refer to
Electronic Control Modules for the procedures.
(9) Remove the nuts from the HVAC housing
mounting studs on the engine compartment side of
the dash panel.
(10) Remove the nuts that secure the HVAC hous-
ing to the mounting studs on the passenger compart-
ment side of the dash panel (Fig. 8).
(11) Pull the HVAC housing rearward far enough
for the mounting studs and the evaporator conden-
sate drain tube to clear the dash panel holes.
(12) Remove the HVAC housing from the vehicle.
REMOVAL - HVAC HOUSING INLET BAFFLE
(1) Remove the HVAC housing from the vehicle.
(Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION/HVAC HOUSING - REMOVAL)
(2) Slide the HVAC housing inlet baffle (Fig. 9) all
the way to one side of the cowl plenum opening.
(3)
Pull downwards sharply and firmly on the oppo-
site side of the HVAC housing inlet baffle to disengage
the snap features from the cowl plenum opening.
(4) Remove the HVAC housing inlet baffle from the
cowl plenum panel.
DISASSEMBLY
(1) Place the HVAC housing upside down on a
work bench.
(2) Remove the screw that secures the floor duct to
the bottom of the HVAC housing and slide the floor
duct off of the center heat duct adaptor.
(3) Unsnap the center heat duct adaptor from the
bottom of the HVAC housing and remove the screw
that was hidden by the adaptor.
(4) Remove the remaining screws on the bottom of
the HVAC housing that secure the two housing
halves together.
(5) Place the HVAC housing right side up on the
work bench.
(6) Separate the top half of the HVAC housing
from the bottom half and set it aside.
ASSEMBLY
(1) Position the top half of the HVAC housing over
the bottom half. Be certain that the mode door pivot
pins are properly inserted in their pivot holes.
(2) Place the HVAC housing upside down on the
work bench.
(3)
Install and tighten the screws on the bottom of
the HVAC housing that secure the two housing halves
together. Tighten the screws to 2.2 N´m (20 in. lbs.).
(4) Snap the center heat duct adaptor onto the bot-
tom of the HVAC housing.
(5) Slide the floor duct onto the center heat duct
adaptor and secure it with a screw to the bottom of
the HVAC housing. Tighten the mounting screw to
2.2 N´m (20 in. lbs.).
Fig. 8 HVAC HOUSING REMOVE/INSTALL
1 - BODY ASSEMBLY
2 - HVAC HOUSING
Fig. 9 HVAC HOUSING INLET BAFFLE REMOVE/
INSTALL
1 - RIGHT A-PILLAR
2 - INLET BAFFLE
3 - COWL PLENUM OPENING
24 - 36 DISTRIBUTIONBR/BE
HVAC HOUSING (Continued)