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.
(5) Remove the mode door actuator from the distri-
bution housing.
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 - FRONT24-29
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. 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 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.
WARNING: THE HEAT SINK FOR THE BLOWER
MOTOR POWER MODULE MAY GET VERY HOT
DURING NORMAL OPERATION. IF THE BLOWER
MOTOR WAS TURNED ON PRIOR TO SERVICING
THE BLOWER MOTOR POWER MODULE, WAIT
FIVE MINUTES TO ALLOW THE HEAT SINK TO
COOL BEFORE PERFORMING DIAGNOSIS OR SER-
VICE. FAILURE TO TAKE THIS PRECAUTION CAN
RESULT IN PERSONAL INJURY.
24 - 30 CONTROLS - FRONTRS
MODE DOOR ACTUATOR (Continued)
(1) Disconnect and isolate the negative battery
cable.
(2) Remove the glove box from the instrument
panel (Refer to 23 - BODY/INSTRUMENT PANEL/
GLOVE BOX - REMOVAL).
(3) Disconnect the two wire harness connectors
from the blower motor power module (Fig. 21).
(4) Remove the two screws that secure the blower
motor power module to the HVAC housing.
(5) Remove the blower motor power module from
the HVAC housing.
INSTALLATION
(1) Position the blower motor power module into
the HVAC housing.
(2) Install the two screws that secure the blower
motor power module to the HVAC housing. Tighten
the screws to 2 N´m (17 in. lbs.).
(3) Connect the two wire connectors to the blower
motor power module.
(4) Install the glove box (Refer to 23 - BODY/IN-
STRUMENT PANEL/GLOVE BOX - INSTALLA-
TION).
(5) Reconnect the negative battery cable.
RECIRCULATION DOOR
ACTUATOR
DESCRIPTION
The recirculation door actuator is a reversible,
12-volt direct current (DC), servo motor. The single
recirculation door actuator is located on the passen-
ger side end of the HVAC housing, on the air inlet
housing. The recirculation door actuator is mechani-
cally connected to the recirculation-air door. The
recirculation door actuator is interchangeable with
the actuators for the blend-air door(s) and 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 air inlet housing. Each actuator also has an iden-
tical output shaft with splines that connects it to the
linkage that drives the recirculation-air door. The
recirculation door actuator does not require mechan-
ical indexing to the recirculation-air door, as it is
electronically calibrated by the A/C-heater control.
OPERATION
The recirculation door actuator is connected to the
heater-A/C control module through the vehicle elec-
trical system by a dedicated two-wire lead and con-
nector of the HVAC wire harness. The recirculation
door actuator can move the recirculation-air 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 recirculation-air door
will move in one direction.
When the A/C-heater control makes the voltage to
both connections high or both connections low, the
recirculation-air door stops and will not move. The
A/C-heater control uses a feedback signal positioning
system to monitor the operation and relative position
of the recirculation door actuator and the recircula-
tion-air door. The A/C-heater control learns the recir-
culation-air door stop positions during the calibration
procedure and will store a diagnostic trouble code
(DTC) for any problems it detects in the recirculation
door actuator circuits.
The recirculation door actuator is diagnosed using
a scan tool (Refer to 24 - HEATING & AIR CONDI-
TIONING - DIAGNOSIS AND TESTING and to 24 -
HVAC Electrical Diagnostics for more information).
The recirculation door actuator cannot be adjusted
or repaired and, if faulty or damaged, it must be
replaced.
Fig. 21 Blower Motor Power Module - Typical
1 - POWER MODULE
2 - LOWER GLOVE BOX OPENING REINFORCEMENT
3 - HVAC HOUSING
RSCONTROLS - FRONT24-31
POWER MODULE - BLOWER MOTOR (Continued)
CONTROLS - REAR
TABLE OF CONTENTS
page page
A/C-HEATER CONTROL
DESCRIPTION.........................33
OPERATION...........................33
REMOVAL.............................33
INSTALLATION.........................34
BLEND DOOR ACTUATOR
DESCRIPTION.........................34
OPERATION...........................35
REMOVAL.............................35
INSTALLATION.........................35
BLOWER MOTOR RELAY
DESCRIPTION.........................36
OPERATION...........................36
REMOVAL.............................37
INSTALLATION.........................37
BLOWER MOTOR RESISTOR BLOCK
DESCRIPTION.........................37OPERATION...........................37
DIAGNOSIS AND TESTING
REAR BLOWER MOTOR RESISTOR
BLOCK.............................38
REMOVAL.............................38
INSTALLATION.........................39
MODE DOOR ACTUATOR - REAR
DESCRIPTION.........................39
OPERATION...........................39
REMOVAL.............................39
INSTALLATION.........................40
POWER MODULE - REAR BLOWER MOTOR
DESCRIPTION.........................40
OPERATION...........................40
REMOVAL.............................41
INSTALLATION.........................41
A/C-HEATER CONTROL
DESCRIPTION
The rear heating-A/C system is controlled by rota-
ry-type blower motor and temperature controls, cen-
trally mounted directly into the headliner, or if
equipped with the available DVD player, located in
the player housing. 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 negative battery
cable.
(2) If the rear A/C-heater control is mounted in the
headliner, use a trim stick or another suitable wide
flat bladed tool and gently pry the top edge of the
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 and bezel
assembly rearward far enough to access the wire har-
ness connector 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 and bezel
assembly from the headliner.
(6) If the rear A/C-heater control is mounted in the
video screen housing, remove the housing from the
headliner (Refer to 8 - ELECTRICAL/AUDIO/VIDEO
SCREEN - REMOVAL).
(7) Remove the three screws that secure the rear
A/C-heater control to the bezel or video screen hous-
ing, depending on application and remove the control
(Fig. 2).
RSCONTROLS - REAR24-33
INSTALLATION
(1) Position the rear A/C-heater control onto the
bezel or video screen housing, depending on applica-
tion.
(2) Install the three screws that secure the rear
A/C-heater control to the bezel or video screen hous-
ing. Tighten the screws to 2 N´m (17 in. lbs.).(3) If the rear A/C-heater control is to be mounted
into the headliner, position the rear A/C-heater con-
trol near the headliner and connect the wire harness
connector to the rear of the control.
(4) Insert the locator tabs on the back of the rear
control bezel over the forward edge of the headliner
opening.
(5) 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 and by using hand
pressure, press the top edge of the bezel upward
until the two snap clips fully seat into their recepta-
cles.
(6) If the rear A/C-heater control is mounted to the
video screen housing, install the video screen to the
headliner (Refer to 8 - ELECTRICAL/AUDIO/VIDEO
SCREEN - INSTALLATION).
(7) Reconnect the negative battery cable.
(8) Using the DRB-IIItscan tool, reset the Rear
Temperature Selector calibration values.
(9) Verify that the Actuator Calibration of the
Front Control has passed. If an Actuator Calibration
has not passed correct any errors before proceeding
further.
(10) Rotate the Rear Temperature Selector counter
clockwise to the Cold Position, allow the Selector to
remain in the Cold Position for 5 seconds.
(11) Rotate the Rear Temperature Selector Clock-
wise to the Hot Position, allow the Selector to remain
in the Cold Position for 5 seconds.
(12) 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.
Fig. 1 A/C-Heater Control - Rear
1 - TRIM STICK
2 - BEZEL
3 - REAR A/C-HEATER CONTROL
4 - HEADLINER
Fig. 2 Heater-A/C Control Bezel
1 - BEZEL/VIDEO SCREEN HOUSING (AS EQUIPPED)
2 - SNAP CLIP (2)
3 - REAR A/C-HEATER CONTROL
4 - SCREW (3)
5 - BEZEL LOCATOR TAB (2)
24 - 34 CONTROLS - REARRS
A/C-HEATER CONTROL (Continued)
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
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 blend door
actuator (Fig. 3).
(7) Remove the two screws that secure the blend
door actuator to the rear HVAC housing.
(8) Pull the blend door actuator away from the
rear HVAC housing far enough to disengage the
actuator output shaft from the rear blend door pivot.(9) Raise the blend door actuator far enough to
access and disconnect the rear HVAC wire harness
connector from the actuator.
(10) Remove the rear blend door actuator from
between the rear HVAC housing and the quarter
inner panel.
INSTALLATION
(1) Position the blend door actuator between the
rear HVAC housing and the quarter inner panel.
(2) Connect the rear HVAC wire harness connector
to the rear blend door actuator.
(3) Position the rear blend 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 blend air door pivot.
(4) Install the two screws that secure the rear
blend 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. 3 Rear HVAC Mode Door Actuator
1 - SCREW (2)
2 - MODE DOOR ACTUATOR
3 - SCREW (2)
4 - CONNECTOR
5 - BLEND DOOR ACTUATOR
6 - WIRE HARNESS CONNECTOR
RSCONTROLS - REAR24-35
BLEND DOOR ACTUATOR (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).
BLOWER MOTOR RELAY
DESCRIPTION
The rear blower motor relay is a International
Standards Organization (ISO)-type relay (Fig. 4).
Relays conforming to the ISO specifications have
common physical dimensions, current capacities, ter-
minal patterns, and terminal functions. The rear
blower motor relay is located in the integrated power
module (IPM) in the engine compartment. See the
fuse and relay map on the inner surface of the cover
of the IPM for rear blower motor relay identification
and location.
The black, molded plastic case is the most visible
component of the rear 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.
Fig. 4 Rear Blower Motor Relay
24 - 36 CONTROLS - REARRS
BLEND DOOR ACTUATOR (Continued)
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.
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 negative battery
cable.
(2) Remove the cover from the integrated power
module (IPM) (Fig. 5).
NOTE: Refer to the fuse and relay map on the inner
surface of the cover of the IPM for rear blower
motor relay identification and location.
(3) Remove the rear blower motor relay from the
IPM.
INSTALLATION
NOTE: Refer to the fuse and relay map on the inner
surface of the cover of the integrated power module
(IPM) for rear blower motor relay identification and
location.
(1) Position the rear blower motor relay to the
proper receptacle in the IPM.
(2) Align the rear blower motor relay terminals
with the terminal cavities in the IPM receptacle.
(3) Push down firmly on the rear blower motor
relay until the terminals are fully seated in the ter-
minal cavities.
(4) Install the cover onto the IPM.
(5) Reconnect the negative battery cable.
BLOWER MOTOR RESISTOR
BLOCK
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.
Fig. 5 Rear Blower Motor Relay
1 - INTEGRATED POWER MODULE (IPM)
2 - REAR BLOWER MOTOR RELAY
3 - FRONT CONTROL MODULE (FCM)
RSCONTROLS - REAR24-37
BLOWER MOTOR RELAY (Continued)