affecting comfort levels, such as solar heat gain or
evaporative heat loss. The ATC system logic responds
to the infrared sensor inputs by calculating and
adjusting the air flow temperature and air flow rate
needed to properly obtain and maintain the individ-
ually selected comfort level temperatures of both the
driver and passenger seat occupants. The ATC heat-
er-A/C control module continually monitors the infra-
red sensor circuits, and will store a Diagnostic
Trouble Code (DTC) for any problem it detects. This
DTC information can be retrieved and the infrared
temperature sensor diagnosed using a DRBIIItscan
tool. Refer to Body Diagnostic Procedures.
MODE DOOR ACTUATOR
DESCRIPTION
The mode door actuator is a reversible, 12-volt
Direct Current (DC), servo motor. The single mode
door actuator is located on the driver's side end of
the HVAC housing, close to the top of the distribution
housing. The mode door actuator is mechanically con-
nected to the mode door.
The mode door actuator is interchangeable with
the actuators for the blend air door(s) and the recir-
culation air door. Each actuator is contained within
an identical black molded plastic housing with an
integral wire connector receptacle. Two integral
mounting tabs allow the actuator to be secured with
two screws to the distribution housing. Each actuator
also has an identical output shaft with splines that
connects it to the linkage that drives the mode door.
The mode door actuator does not require mechanical
indexing to the mode door linkage, as it is electroni-
cally calibrated by the heater-A/C control module.
OPERATION
The mode door actuator is connected to the A/C-
heater control through the vehicle electrical system
by a dedicated two-wire lead and connector from the
HVAC wire harness. The mode door actuator can
move the mode door in two directions. When the A/C-
heater control pulls the voltage on one side of the
motor connection high and the other connection low,
the mode door will move in one direction. When the
A/C-heater control reverses the polarity of the volt-
age to the motor, the mode door moves in the oppo-
site direction. When the A/C-heater control makes
the voltage to both connections high or both connec-
tions low, the mode door stops and will not move.
These same motor connections also provide a feed-
back signal to the A/C-heater control. This feedback
signal allows the A/C-heater control to monitor the
operation and relative position of the mode door
actuator and the mode door. The A/C-heater control
learns the mode door stop positions during the cali-
bration procedure and will store a diagnostic trouble
code (DTC) for any problems it detects in the mode
door actuator circuits.
The mode door actuator can be diagnosed using a
DRBIIItscan tool. Refer to Body Diagnostic Proce-
dures for more information. The mode door actuator
cannot be adjusted or repaired and, if damaged or
faulty, it must be replaced.
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 ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the silencer from beneath the driver
side end of the instrument panel (Refer to 23 -
BODY/INSTRUMENT PANEL/INSTRUMENT
PANEL SILENCER - REMOVAL).
(3) Disconnect the wire harness connector from the
mode door actuator (Fig. 20).
(4) Remove the two screws that secure the mode
door actuator to the HVAC distribution housing.
Fig. 19 Infrared Temperature Sensor
1 - INSTRUMENT PANEL CENTER BEZEL
2 - CENTER BEZEL OUTLETS
3 - INFRARED TEMPERATURE SENSOR
24 - 30 CONTROLS - FRONTRS
INFRARED TEMPERATURE SENSOR (Continued)
(5) Remove the mode door actuator from the distri-
bution housing.
INSTALLATION
(1) Position the mode door actuator onto the HVAC
distribution housing. If necessary, rotate the actuator
slightly to align the splines on the actuator output
shaft with those in the mode door linkage.
(2) Install the two screws that secure the mode
door actuator to the distribution housing. Tighten the
screws to 2 N´m (17 in. lbs.).
(3) Connect the wire harness connector to the
mode door actuator.
(4) Install the silencer under the driver side end of
the instrument panel (Refer to 23 - BODY/INSTRU-
MENT PANEL/INSTRUMENT PANEL SILENCER -
INSTALLATION).
(5) Reconnect the negative battery cable.
(6) Perform the A/C-heater control calibration pro-
cedure (Refer to 24 - HEATING & AIR CONDITION-
ING/CONTROLS - FRONT/A/C-HEATER CONTROL
- STANDARD PROCEDURE - HEATER-A/C CON-
TROL CALIBRATION).
POWER MODULE - BLOWER
MOTOR
DESCRIPTION
A blower motor power module is used on this
model when it is equipped with the optional Auto-
matic Temperature Control (ATC) system. Modelsequipped with the standard manual heater-A/C sys-
tem use a blower motor resistor block, instead of the
blower motor power module (Refer to 24 - HEATING
& AIR CONDITIONING/CONTROLS/BLOWER
MOTOR RESISTOR BLOCK - DESCRIPTION).
The blower motor power module is mounted to the
rear of the HVAC housing, directly behind the glove
box opening in the instrument panel. The module
consists of a molded plastic mounting plate with two
integral connector receptacles. Concealed behind the
mounting plate is the power module electronic cir-
cuitry and a large finned, heat sink. The blower
motor power module is accessed for service by remov-
ing the glove box from the instrument panel.
OPERATION
The blower motor power module is connected to the
vehicle electrical system through a dedicated lead
and connector from the instrument panel wire har-
ness. A second connector receptacle receives a wire
lead connector from the blower motor. The blower
motor power module allows the microprocessor-based
Automatic Temperature Control (ATC) heater-A/C
control module to calculate and provide infinitely
variable blower motor speeds based upon either man-
ual blower switch input or the ATC programming
using a Pulse Width Modulated (PWM) circuit strat-
egy. The PWM voltage is applied to a comparator cir-
cuit which compares the PWM signal voltage to the
blower motor feedback voltage. The resulting output
drives the power module circuitry, which adjusts the
voltage output received from the blower motor relay
to change or maintain the desired blower speed. The
blower motor power module is diagnosed using a
DRBIIItscan tool. Refer to Body Diagnostic Proce-
dures.
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 ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
Fig. 20 Mode Door Actuator - LHD Shown, RHD
Typical
1 - WIRE HARNESS CONNECTOR
2 - MODE DOOR ACTUATOR
3 - SCREW (2)
4 - DRIVER BLEND DOOR ACTUATOR (DUAL-ZONE)
5 - HEATER CORE
6 - BLEND DOOR ACTUATOR (SINGLE ZONE) OR PASSENGER
BLEND DOOR ACTUATOR (DUAL-ZONE)
RSCONTROLS - FRONT24-31
MODE DOOR ACTUATOR (Continued)
(6) If required, remove the three screws that
secure the rear A/C-heater control to the bezel and
remove the control from the bezel (Fig. 2).
INSTALLATION
(1) If removed, position the rear A/C-heater control
onto the bezel.
(2) If removed, install the three screws that secure
the rear A/C-heater control to the bezel. Tighten the
screws to 2 N´m (17 in. lbs.).
(3) Position the rear A/C-heater control near the
headliner.
(4) Connect the wire harness connector to the rear
A/C-heater control.
(5) Insert the locator tabs on the back of the rear
A/C-heater control bezel over the forward edge of the
headliner opening.
(6) Slide the rear A/C-heater control bezel forward
far enough to align the snap clips on the bezel with
the receptacles on the headliner.
(7) Using hand pressure, press the top edge of the
rear A/C-heater control bezel upward until the two
snap clips are fully seated in their receptacles.
(8) Reconnect the battery negative cable.
(9) Using the DRB-IIItreset the Rear Tempera-
ture Selector calibration values.
(10) Verify that the Actuator Calibration of the
Front Control has passed. If an Actuator Calibration
has not passed correct any errors before proceeding
further.
(11) Rotate the Rear Temperature Selector counter
clockwise to the Cold Position, allow the Selector to
remain in the Cold Position for 5 seconds.(12) Rotate the Rear Temperature Selector Clock-
wise to the Hot Position, allow the Selector to remain
in the Cold Position for 5 seconds.
(13) Calibration is now complete.
BLEND DOOR ACTUATOR
DESCRIPTION
The rear blend door actuator is a reversible,
12-volt Direct Current (DC), servo motor. The single
blend door actuator is located on the outboard side of
the rear HVAC housing, below the mode door actua-
tor. The blend door actuator is mechanically con-
nected to the blend air door.
The rear blend door actuator is interchangeable
with the actuator for the mode door. Each actuator is
contained within an identical black molded plastic
housing with an integral wire connector receptacle.
Two integral mounting tabs allow the actuator to be
secured with two screws to the rear HVAC housing.
Each actuator also has an identical output shaft with
splines that connects it to the pivot or linkage of the
proper door. The rear blend door actuator does not
require mechanical indexing to the blend air door
pivot, as it is electronically calibrated by the front
heater-A/C control module.
OPERATION
The rear blend door actuator is connected to the
front heater-A/C control module through the vehicle
electrical system by a dedicated two-wire take out
and connector of the rear HVAC wire harness. The
blend door actuator can move the blend air door in
two directions. When the front heater-A/C control
module pulls the voltage on one side of the motor
connection high and the other connection low, the
blend air door will move in one direction. When the
module reverses the polarity of the voltage to the
motor, the blend air door moves in the opposite direc-
tion. When the module makes the voltage to both
connections high or both connections low, the blend
air door stops and will not move. These same motor
connections also provide a feedback signal to the
front heater-A/C control module. This feedback signal
allows the module to monitor the operation and rela-
tive positions of the blend door actuator and the
blend air door. The front heater-A/C control module
learns the blend air door stop positions during the
calibration procedure and will store a Diagnostic
Trouble Code (DTC) for any problems it detects in
the blend door actuator circuits.
The rear blend door actuator can be diagnosed
using a DRBIIItscan tool. Refer to Body Diagnostic
Procedures for more information. The rear blend door
Fig. 2 Heater-A/C Control Bezel
1 - BEZEL
2 - SNAP CLIP (2)
3 - HEATER-A/C CONTROL
4 - SCREW (3)
5 - LOCATOR TAB (2)
RSCONTROLS - REAR24-35
A/C-HEATER CONTROL (Continued)
BLOWER MOTOR RELAY
DESCRIPTION
The blower motor relay is a International Stan-
dards Organization (ISO) mini-relay (Fig. 4). Relays
conforming to the ISO specifications have common
physical dimensions, current capacities, terminal pat-
terns, and terminal functions. The ISO mini-relay
terminal functions are the same as a conventional
ISO relay. However, the ISO mini-relay terminal pat-
tern (or footprint) is different, the current capacity is
lower, and the physical dimensions are smaller than
those of the conventional ISO relay. The rear blower
motor relay is located in the Integrated Power Mod-
ule (IPM), which is in the engine compartment near
the battery. See the fuse and relay layout map
molded into the inner surface of the IPM cover for
rear blower motor relay identification and location.
The black, molded plastic case is the most visible
component of the blower motor relay. Five male
spade-type terminals extend from the bottom of the
base to connect the relay to the vehicle electrical sys-
tem, and the ISO designation for each terminal is
molded into the base adjacent to each terminal. The
ISO terminal designations are as follows:
²30 (Common Feed)- This terminal is con-
nected to the movable contact point of the relay.
²85 (Coil Ground)- This terminal is connected
to the ground feed side of the relay control coil.
²86 (Coil Battery)- This terminal is connected
to the battery feed side of the relay control coil.
²87 (Normally Open)- This terminal is con-
nected to the normally open fixed contact point of the
relay.²87A (Normally Closed)- This terminal is con-
nected to the normally closed fixed contact point of
the relay.
The rear blower motor relay cannot be adjusted or
repaired. If the relay is damaged or faulty, it must be
replaced.
OPERATION
The rear blower motor relay is an electromechani-
cal switch that uses a low current input from the
Front Control Module (FCM) to control the high cur-
rent output to the rear blower motor resistor (man-
ual heater-A/C control) or rear blower motor power
module (ATC heater-A/C control). The movable com-
mon feed contact point is held against the fixed nor-
mally closed contact point by spring pressure. When
the relay coil is energized, an electromagnetic field is
produced by the coil windings. This electromagnetic
field draws the movable relay contact point away
from the fixed normally closed contact point, and
holds it against the fixed normally open contact
point. When the relay coil is de-energized, spring
pressure returns the movable contact point back
against the fixed normally closed contact point. The
resistor or diode is connected in parallel with the
relay coil in the relay, and helps to dissipate voltage
spikes and electromagnetic interference that can be
generated as the electromagnetic field of the relay
coil collapses.
The rear blower motor relay terminals are con-
nected to the vehicle electrical system through a
receptacle in the Integrated Power Module (IPM).
The inputs and outputs of the rear blower motor
relay include:
²The common feed terminal (30) receives a bat-
tery current input from the battery through a B(+)
circuit at all times.
²The coil ground terminal (85) receives a ground
input through the front/rear blower motor relay con-
trol circuit only when the FCM electronically pulls
the control circuit to ground.
²The coil battery terminal (86) receives a battery
current input from the battery through a B(+) circuit
at all times.
²The normally open terminal (87) provides a bat-
tery current output to the blower motor resistor
(manual heater-A/C control) or blower power module
(ATC heater-A/C control) through a fuse in the IPM
on the fused rear blower motor relay output circuit
only when the blower motor relay coil is energized.
²The normally closed terminal (87A) is not con-
nected to any circuit in this application, but provides
a battery current output only when the rear blower
motor relay coil is de-energized.
Fig. 4 Rear Blower Motor Relay
RSCONTROLS - REAR24-37
Refer to the appropriate wiring information for
diagnosis and testing of the micro-relay and for com-
plete HVAC wiring diagrams.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Unlatch and remove the cover from the Inte-
grated Power Module (IPM) (Fig. 5).
(3) See the fuse and relay layout map molded into
the inner surface of the IPM cover for rear blower
motor relay identification and location.
(4) Remove the rear blower motor relay from the
IPM.
INSTALLATION
(1) See the fuse and relay layout map molded into
the inner surface of the Integrated Power Module
(IPM) cover for rear blower motor relay identification
and location.
(2) Position the rear blower motor relay to the
proper receptacle in the IPM.
(3) Align the rear blower motor relay terminals
with the terminal cavities in the IPM relay recepta-
cle.
(4) Push down firmly on the rear blower motor
relay until the terminals are fully seated in the ter-
minal cavities in the IPM receptacle.
(5) Install the cover onto the IPM.
(6) Reconnect the battery negative cable.
BLOWER MOTOR RESISTOR
DESCRIPTION
A rear blower motor resistor is used on this model
when it is equipped with the manual heater-A/C sys-
tem. Models equipped with the optional Automatic
Temperature Control (ATC) system use a rear blower
motor power module, instead of the blower motor
resistor block (Refer to 24 - HEATING & AIR CON-
DITIONING/CONTROLS/POWER MODULE -
DESCRIPTION). The rear blower motor resistor
block is mounted to the rear HVAC housing, directly
above the expansion valve. The resistor block con-
sists of a molded plastic mounting plate with an inte-
gral connector receptacle. Concealed behind the
mounting plate is an electrical circuit board with two
resistors and a thermal fuse. The rear blower motor
resistor block is accessed for service by removing the
right quarter and D-pillar trim panels.
OPERATION
The rear blower motor resistor block is connected
to the vehicle electrical system through a dedicated
take out and connector of the rear HVAC wire har-
ness. The blower motor resistor has an electrical cir-
cuit board with two resistors, each of which will
reduce the current flow through the blower motor to
change the blower motor speed. The blower motor
switch in the manual heater-A/C system directs the
ground path for the rear blower motor through the
correct resistor to obtain the selected speed.
With the blower motor switch in the lowest speed
position, the ground path for the motor is applied
through both resistors. Each higher speed selected
with the blower motor switch applies the blower
motor ground path through fewer of the resistors,
increasing the blower motor speed. When the blower
motor switch is in the highest speed position, the
blower motor resistors are bypassed and the blower
motor receives a direct path to ground through the
blower motor switch.
The rear blower motor resistor block cannot be
adjusted or repaired and, if faulty or damaged, it
must be replaced.
DIAGNOSIS AND TESTING - REAR BLOWER
MOTOR RESISTOR BLOCK
For circuit descriptions and diagrams, refer to the
appropriate wiring information. The wiring informa-
tion includes wiring diagrams, proper wire and con-
nector repair procedures, further details on wire
harness routing and retention, as well as pin-out and
location views for the various wire harness connec-
tors, splices and grounds.
Fig. 5 Integrated Power Module - Typical
1 - BATTERY THERMAL GUARD
2 - INTEGRATED POWER MODULE
3 - FRONT CONTROL MODULE
24 - 38 CONTROLS - REARRS
BLOWER MOTOR RELAY (Continued)
OPERATION
The rear mode door actuator is connected to the
front heater-A/C control module through the vehicle
electrical system by a dedicated two-wire take out
and connector of the rear HVAC wire harness. The
rear mode door actuator can move the mode door in
two directions. When the front heater-A/C control
module pulls the voltage on one side of the motor
connection high and the other connection low, the
rear mode door will move in one direction. When the
module reverses the polarity of the voltage to the
motor, the rear mode door moves in the opposite
direction. When the module makes the voltage to
both connections high or both connections low, the
mode door stops and will not move. These same
motor connections also provide a feedback signal to
the front heater-A/C control module. This feedback
signal allows the module to monitor the operation
and relative positions of the rear mode door actuator
and the mode door. The front heater-A/C control mod-
ule learns the rear mode door stop positions during
the calibration procedure and will store a Diagnostic
Trouble Code (DTC) for any problems it detects in
the mode door actuator circuits.
The rear mode door actuator can be diagnosed
using a DRBIIItscan tool. Refer to Body Diagnostic
Procedures for more information. The rear mode door
actuator cannot be adjusted or repaired and, if dam-
aged or faulty, it must be replaced.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the right quarter trim panel and right
D-pillar trim panel from the quarter inner panel
(Refer to 23 - BODY/INTERIOR/QUARTER TRIM
PANEL - REMOVAL).
(3) Remove the two screws that secure the top of
the quarter trim panel attaching bracket to the quar-
ter inner panel.
(4) Remove the screw that secures the back of the
rear HVAC housing to the right D-pillar.
(5) Remove the screw that secures the front of the
rear HVAC housing to the right quarter inner panel.
(6) Carefully pull the top of the rear HVAC hous-
ing away from the right quarter inner panel far
enough to reach between the rear HVAC housing and
the quarter inner panel to access the rear mode door
actuator (Fig. 7).
(7) Remove the two screws that secure the mode
door actuator to the rear HVAC housing.
(8) Pull the mode door actuator away from the
rear HVAC housing far enough to disengage the
actuator output shaft from the mode door linkage.(9) Raise the mode door actuator far enough to
access and disconnect the rear HVAC wire harness
connector from the actuator
(10) Remove the rear mode door actuator from
between the rear HVAC housing and the quarter
inner panel.
INSTALLATION
(1) Position the mode door actuator between the
rear HVAC housing and the quarter inner panel.
(2) Reconnect the rear HVAC wire harness connec-
tor to the rear mode door actuator.
(3) Position the rear mode door actuator onto the
rear HVAC housing. If necessary, rotate the actuator
slightly to align the splines on the actuator output
shaft with those in the mode door linkage.
(4) Install the two screws that secure the rear
mode door actuator to the rear HVAC housing.
Tighten the screws to 2 N´m (17 in. lbs.).
(5) Push the top of the rear HVAC housing back
into position against the right quarter inner panel.
Fig. 7 Rear HVAC Blend Door Actuator
1 - SCREW (2)
2 - MODE DOOR ACTUATOR
3 - SCREW (2)
4 - CONNECTOR
5 - BLEND DOOR ACTUATOR
6 - WIRE HARNESS CONNECTOR
24 - 40 CONTROLS - REARRS
MODE DOOR ACTUATOR - REAR (Continued)
(6) Install the screw that secures the front of the
rear HVAC housing to the right quarter inner panel.
Tighten the screw to 11 N´m (97 in. lbs.).
(7) Install the screw that secures the back of the
rear HVAC housing to the right D-pillar. Tighten the
screw to 11 N´m (97 in. lbs.).
(8) Install the two screws that secure the top of
the quarter trim panel attaching bracket to the quar-
ter inner panel. Tighten the screws to 2 N´m (17 in.
lbs.).
(9) Reinstall the right quarter trim panel and
right D-pillar trim panel onto the quarter inner
panel (Refer to 23 - BODY/INTERIOR/QUARTER
TRIM PANEL - INSTALLATION).
(10) Reconnect the battery negative cable.
(11) Perform the heater-A/C control calibration
procedure (Refer to 24 - HEATING & AIR CONDI-
TIONING/CONTROLS - FRONT/A/C-HEATER CON-
TROL - STANDARD PROCEDURE - HEATER-A/C
CONTROL CALIBRATION).
POWER MODULE - REAR
BLOWER MOTOR
DESCRIPTION
A rear blower motor power module is used on this
model when it is equipped with the optional Auto-
matic Temperature Control (ATC) system. Models
equipped with the standard manual heater-A/C sys-
tem use a blower motor resistor block , instead of the
blower motor power module (Refer to 24 - HEATING
& AIR CONDITIONING/CONTROLS/BLOWER
MOTOR RESISTOR BLOCK - DESCRIPTION).
The rear blower motor power module is installed in
the back of the rear HVAC housing, directly above
the expansion valve. The module consists of a molded
plastic mounting plate with two integral connector
receptacles. Concealed behind the mounting plate
within the evaporator housing is the power module
electronic circuitry and a large finned, heat sink. The
power module is accessed for service by removing the
right quarter and D-pillar trim panels.
OPERATION
The rear blower motor power module is connected
to the vehicle electrical system through a dedicated
take out and connector of the rear HVAC wire har-
ness. A second connector receptacle receives the pig-
tail wire connector from the rear blower motor. The
rear blower motor power module allows the micropro-
cessor-based Automatic Temperature Control (ATC)
heater-A/C control module to calculate and provide
infinitely variable blower motor speeds based upon
either manual blower switch input or the ATC pro-
gramming using a Pulse Width Modulated (PWM)circuit strategy. The PWM voltage is applied to a
comparator circuit which compares the PWM signal
voltage to the blower motor feedback voltage. The
resulting output drives the power module circuitry,
which adjusts the voltage output received from the
rear blower motor relay to change or maintain the
desired blower speed. The rear blower motor power
module is diagnosed using a DRBIIItscan tool. Refer
to Body Diagnostic Procedures.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the right quarter trim panel and right
D-pillar trim panel from the quarter inner panel
(Refer to 23 - BODY/INTERIOR/QUARTER TRIM
PANEL - REMOVAL).
(3) Disconnect the rear HVAC wire harness con-
nector from the rear blower motor power module
(Fig. 8).
(4) Disconnect the rear blower motor pigtail wire
connector from the rear blower motor power module.
(5) Remove the two screws that secure the rear
blower motor power module to the rear HVAC hous-
ing.
(6) Remove the rear blower motor power module
from the rear HVAC housing.
Fig. 8 Rear Blower Motor Power Module
1 - REAR HVAC HOUSING
2 - SCREW (2)
3 - D-PILLAR
4 - REAR BLOWER MOTOR PIGTAIL WIRE
5 - REAR HVAC WIRE HARNESS
6 - EXPANSION VALVE
7 - REAR BLOWER MOTOR POWER MODULE
RSCONTROLS - REAR24-41
MODE DOOR ACTUATOR - REAR (Continued)
blower motor to regulate the blower motor ground
path it provides. The blower motor and wheel are
used to control the velocity of air moving through the
HVAC housing by spinning the blower wheel within
the housing at the selected speed or, in the ATC sys-
tem, at the selected or programmed speed.
DIAGNOSIS AND TESTING - BLOWER MOTOR
BLOWER MOTOR INOPERATIVE
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 ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
For circuit descriptions and diagrams, refer to the
appropriate wiring information. The wiring informa-
tion includes wiring, diagrams, proper wire and con-
nector repair procedures, further details on wire
harness routing and retention, as well as pin-out and
location views for the various wire harness connec-
tors, splices and grounds.
BLOWER MOTOR ELECTRICAL DIAGNOSIS
(1) Check the fuse (Fuse 10 - 40 ampere) in the
Integrated Power Module (IPM). 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 On position. Be
certain that the A/C-heater control power is turned
on. Check for battery voltage at the fuse (Fuse 10 -
40 ampere) in the IPM. If OK, go to Step 3. If not
OK, check the front blower motor relay.
(3) Turn the ignition switch to the Off position.
Disconnect and isolate the battery negative cable.
Disconnect the front HVAC wire harness connector
for the front blower motor resistor block (Manual
Temperature Control) or the front blower motor
power module (Automatic Temperature Control) from
the resistor or module connector receptacle. Recon-
nect the battery negative cable. Turn the ignition
switch to the On position. Be certain that the A/C-
heater control power is turned on. Check for battery
voltage at the fused front blower motor relay output
circuit cavity of the front HVAC wire harness connec-
tor for the front blower motor resistor block (MTC) orthe front blower motor power module (ATC). If OK,
go to Step 4. If not OK, repair the open fused front
blower motor relay output circuit to the IPM as
required.
(4) Turn the ignition switch to the Off position.
Disconnect and isolate the battery negative cable.
Disconnect the front blower motor pigtail wire con-
nector from the connector receptacle of the front
blower motor resistor block (MTC) or the front
blower motor power module (ATC). Use jumper wires
to connect a battery and ground feeds to the blower
motor pigtail wire connector. The blower motor
should operate. If OK with MTC, proceed to diagno-
sis of the front blower motor resistor block (Refer to
24 - HEATING & AIR CONDITIONING/CONTROLS
- FRONT/BLOWER MOTOR RESISTOR - DIAGNO-
SIS AND TESTING). If OK with ATC, use a DRBIII
scan tool to diagnose the front blower motor power
module. Refer to Body Diagnostic information. If not
OK with MTC or ATC, replace the faulty front blower
motor.
BLOWER MOTOR NOISE OR VIBRATION
Refer to the Blower Motor Noise/Vibration Diagno-
sis chart for basic checks of the blower motor when a
vibration or noise is present (Fig. 7).
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.
NOTE: The blower motor is located on the passen-
ger side of the vehicle under the instrument panel.
The blower motor can be removed from the vehicle
without having to remove the HVAC housing.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the passenger side door sill plate and
cowl panel.
(3) Pull back the carpet to access the front lower
air intake screw.
RSDISTRIBUTION - FRONT24-47
BLOWER MOTOR (Continued)