fuse CHRYSLER CARAVAN 2005 Service Manual

(5) Rotate injector and pull injector out of fuel rail.
The clip will stay on the injector.
(6) Check injector O-ring for damage. If O-ring is
damaged, it must be replaced. If injector is reused, a
protective cap must be installed on the injector tip to
prevent damage. Replace the injector clip if it is dam-
aged.
(7) Repeat for remaining injectors.
INSTALLATION
INSTALLATION - 2.4L
The fuel rail must be removed first. Refer to Fuel
Injector Rail Removal in this section.
(1) Before installing an injector the rubber O-ring
must be lubricated with a drop of clean engine oil to
aid in installation.
(2) Install injector clip by sliding open end into the
top slot of the injector. The edge of the receiver cup
will slide into the side slots of clip.
(3) Install injector top end into fuel rail receiver
cap. Be careful not to damage O-ring during installa-
tion (Fig. 14).
(4) Repeat steps for remaining injectors.
(5) Connect fuel injector wiring.
INSTALLATION - 3.3/3.8L
(1) Before installing an injector the rubber O-ring
must be lubricated with a drop of clean engine oil to
aid in installation.
(2) Install injector clip by sliding open end into the
top slot of the injector. The edge of the receiver cup
will slide into the side slots of clip (Fig. 13).
(3) Install injector top end into fuel rail receiver
cap. Be careful not to damage O-ring during installa-
tion (Fig. 13).
(4) Repeat steps for remaining injectors.
(5) Install fuel rail, refer to Fuel Rail in the Fuel
Delivery section.
(6) Connect fuel injector wiring.
(7) Install the Intake Manifold, (Refer to 9 -
ENGINE/MANIFOLDS/INTAKE MANIFOLD -
INSTALLATION)
(8) Connect the negative battery cable.
FUEL PUMP RELAY
DESCRIPTION
The fuel pump relay is located in the PDC. The
inside top of the PDC cover has a label showing relay
and fuse location.
OPERATION
The fuel pump relay supplies battery voltage to the
fuel pump. A buss bar in the Power Distribution Cen-
ter (PDC) supplies voltage to the solenoid side and
contact side of the relay. The fuel pump relay power
circuit contains a fuse between the buss bar in the
PDC and the relay. The fuse is located in the PDC.
Refer to the Wiring Diagrams for circuit information.
The PCM controls the fuel pump relay by switch-
ing the ground path for the solenoid side of the relay
on and off. The PCM turns the ground path off when
the ignition switch is in the Off position. When the
ignition switch is in the On position, the PCM ener-
gizes the fuel pump. If the crankshaft position sensor
does not detect engine rotation, the PCM de-ener-
gizes the relay after approximately one second.
Fig. 14 SERVICING FUEL INJECTOR TYPICAL
1 - FUEL INJECTOR
2 - LOCKING SLOT
3 - FUEL RAIL RECEIVER CUP
14 - 32 FUEL INJECTIONRS
FUEL INJECTOR (Continued)

TRANSMISSION CONTROL
RELAY
DESCRIPTION
The transmission control relay (Fig. 306) is located
in the Intelligent Power Module (IPM), which is
located on the left side of the engine compartment
between the battery and left fender.
OPERATION
The relay is supplied fused B+ voltage, energized by
the PCM/TCM, and is used to supply power to the sole-
noid pack when the transmission is in normal operating
mode. When the relay is ªoffº, no power is supplied to
the solenoid pack and the transmission is in ªlimp-inº
mode. After a controller reset (ignition key turned to the
ªrunº position or after cranking engine), the PCM/TCM
energizes the relay. Prior to this, the PCM/TCM verifies
that the contacts are open by checking for no voltage at
the switched battery terminals. After this is verified,
the voltage at the solenoid pack pressure switches is
checked. After the relay is energized, the PCM/TCM
monitors the terminals to verify that the voltage is
greater than 3 volts.
TRANSMISSION RANGE
SENSOR
DESCRIPTION
The Transmission Range Sensor (TRS) is mounted
to the top of the valve body inside the transaxle andcan only be serviced by removing the valve body. The
electrical connector extends through the transaxle
case (Fig. 307).
The Transmission Range Sensor (TRS) has four
switch contacts that monitor shift lever position and
send the information to the PCM/TCM.
The TRS also has an integrated temperature sen-
sor (thermistor) that communicates transaxle tem-
perature to the TCM and PCM (Fig. 308).
Fig. 306 Transmission Control Relay Location
1 - TRANSMISSION CONTROL RELAY
2 - LEFT FENDER
3 - INTELLIGENT POWER MODULE (IPM)
4 - BATTERY
Fig. 307 Transmission Range Sensor (TRS)
Location
1 - TRANSMISSION RANGE SENSOR
Fig. 308 Transmission Temperature Sensor
1 - TRANSMISSION RANGE SENSOR
2 - TEMPERATURE SENSOR
21 - 130 40TE AUTOMATIC TRANSAXLERS

TRANSMISSION CONTROL
RELAY
DESCRIPTION
The transmission control relay (Fig. 330) is located
in the Intelligent Power Module (IPM), which is
located on the left side of the engine compartment
between the battery and left fender.
OPERATION
The relay is supplied fused B+ voltage, energized by
the PCM/TCM, and is used to supply power to the sole-
noid pack when the transmission is in normal operating
mode. When the relay is ªoffº, no power is supplied to
the solenoid pack and the transmission is in ªlimp-inº
mode. After a controller reset (ignition key turned to the
ªrunº position or after cranking engine), the PCM/TCM
energizes the relay. Prior to this, the PCM/TCM verifies
that the contacts are open by checking for no voltage at
the switched battery terminals. After this is verified,
the voltage at the solenoid pack pressure switches is
checked. After the relay is energized, the PCM/TCM
monitors the terminals to verify that the voltage is
greater than 3 volts.
TRANSMISSION RANGE
SENSOR
DESCRIPTION
The Transmission Range Sensor (TRS) is mounted
to the top of the valve body inside the transaxle andcan only be serviced by removing the valve body. The
electrical connector extends through the transaxle
case (Fig. 331).
The Transmission Range Sensor (TRS) has four
switch contacts that monitor shift lever position and
send the information to the PCM/TCM.
The TRS also has an integrated temperature sen-
sor (thermistor) that communicates transaxle tem-
perature to the TCM and PCM (Fig. 332).
Fig. 330 Transmission Control Relay Location
1 - TRANSMISSION CONTROL RELAY
2 - LEFT FENDER
3 - INTELLIGENT POWER MODULE (IPM)
4 - BATTERY
Fig. 331 Transmission Range Sensor (TRS)
Location
1 - TRANSMISSION RANGE SENSOR
Fig. 332 Transmission Temperature Sensor
1 - TRANSMISSION RANGE SENSOR
2 - TEMPERATURE SENSOR
RS41TE AUTOMATIC TRANSAXLE21 - 281

A/C PERFORMANCE TEMPERATURE AND PRESSURE
Ambient
Temperature21É C
(70É F)27É C
(80É F)32É C
(90É F)38É C
(100É F)43É C
(110É F)
Left Center Panel
Outlet Discharge
Air Temperature1to8ÉC
(34 to 46É F)3to9ÉC
(37 to 49É F)4 to 10ÉC
(39 to 50É F)6to11ÉC
(43 to 52É F)7 to 18É C
(45 to 65É F)
Discharge
Pressure (High
Side Service Port)1034 to 1724
kPa
(150 to 250 psi)1517 to 2275
kPa
(220 to 330 psi)1999 to 2620
kPa
(290 to 380 psi)2068 to 2965
kPa
(300 to 430 psi)2275 to 3421
kPa
(330 to 450 psi)
Suction Pressure
(Low Side Service
Port)103 to 207 kPa
(15 to 30 psi)117 to 221 kPa
(17 to 32 psi)138 to 241 kPa
(20 to 35 psi)172 to 269 kPa
(25 to 39 psi)207 to 345 kPa
(30 to 50 psi)
(8) If the air outlet temperature fails to meet the
specifications in the A/C Performance Temperature
and Pressure chart, or if the compressor discharge
pressure is high, refer to the A/C Pressure Diagnosis
Chart.
A/C PRESSURE DIAGNOSIS
Condition Possible Causes Correction
Rapid A/C compressor clutch
cycling (ten or more cycles
per minute).1. Low refrigerant system
charge.1. See Refrigerant System Leaks in this group.
Test the refrigerant system for leaks. Repair,
evacuate and charge the refrigerant system, if
required.
Equal pressures, but the
compressor clutch does not
engage.1. No refrigerant in the
refrigerant system.1. See Refrigerant System Leaks in this group.
Test the refrigerant system for leaks. Repair,
evacuate and charge the refrigerant system, if
required.
2. Faulty fuse. 2. Check the fuses in the Integrated Power
Module. Repair the shorted circuit or component
and replace the fuses, if required. Refer to Group
8.
3. Faulty A/C compressor
clutch coil.3. See A/C Compressor Clutch Coil in this group.
Test the compressor clutch coil and replace, if
required.
4. Faulty A/C compressor
clutch relay.4. See A/C Compressor Clutch Relay in this
group. Test the compressor clutch relay and relay
circuits. Repair the circuits or replace the relay, if
required.
5. Improperly installed or
faulty evaporator temperature
sensor.5. See Evaporator Temperature Sensor in this
group. Test the sensor and replace, if required.
6. Faulty A/C pressure
transducer.6. See A/C Pressure Transducer in this group.
Test the sensor and replace, if required.
7. Faulty Powertrain Control
Module (PCM).7. Refer to the proper Diagnostic Procedures
manual for testing of the PCM. Test the PCM and
replace, if required.
24 - 8 HEATING & AIR CONDITIONINGRS
HEATING & AIR CONDITIONING (Continued)

A/C COMPRESSOR CLUTCH
RELAY
DESCRIPTION
The compressor clutch relay (Fig. 7) is a Interna-
tional Standards Organization (ISO) mini-relay.
Relays conforming to the ISO specifications have
common physical dimensions, current capacities, ter-
minal patterns, and terminal functions. The ISO
mini-relay terminal functions are the same as a con-
ventional ISO relay. However, the ISO mini-relay ter-
minal pattern (or footprint) is different, the current
capacity is lower, and the physical dimensions are
smaller than those of the conventional ISO relay. The
A/C compressor clutch relay is located in the inte-
grated power module (IPM) in the engine compart-
ment. See the fuse and relay map molded into the
inner surface of the cover of the IPM for A/C com-
pressor clutch relay identification and location.
The black, molded plastic case is the most visible
component of the A/C compressor clutch relay. Five
male spade-type terminals extend from the bottom of
the base to connect the relay to the vehicle electrical
system, 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.
OPERATION
The A/C compressor clutch relay is an electrome-
chanical switch that uses a low current input from
the powertrain control module (PCM) to control the
high current output to the compressor clutch electro-
magnetic coil. The movable common feed contact
point is held against the fixed normally closed con-
tact 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 nor-
mally closed contact point, and holds it against the
fixed normally open contact point. When the relay
coil is de-energized, spring pressure returns the mov-
able contact point back against the fixed normally
closed contact point. The resistor or diode is con-
nected in parallel with the relay coil in the relay, and
helps to dissipate voltage spikes and electromagnetic
interference that can be generated as the electromag-
netic field of the relay coil collapses.
The compressor clutch 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 A/C compressor clutch
relay include:
²The common feed terminal (30) receives a bat-
tery current input from a fuse in the IPM through a
fused B(+) circuit at all times.
²The coil ground terminal (85) receives a ground
input from the PCM through the compressor clutch
relay control circuit only when the PCM electroni-
cally pulls the control circuit to ground.
²The coil battery terminal (86) receives a battery
current input from the PCM through a fused ignition
switch output (run-start) circuit only when the igni-
tion switch is in the On or Start positions.
²The normally open terminal (87) provides a bat-
tery current output to the compressor clutch coil
through the compressor clutch relay output circuit
only when the compressor clutch relay coil is ener-
gized.
²The normally closed terminal (87A) is not con-
nected to any circuit in this application, but provides
a battery current output only when the compressor
clutch relay coil is de-energized.
The A/C compressor clutch relay cannot be
repaired and, if faulty or damaged, it must be
replaced. Refer to the appropriate wiring information
for diagnosis and testing of the micro-relay and for
complete HVAC wiring diagrams.
Fig. 7 A/C Compressor Clutch Relay
24 - 18 CONTROLS - FRONTRS

REMOVAL
(1) Disconnect and isolate the negative battery
cable.
(2) Remove the cover from the integrated power
module (IPM) (Fig. 8).
NOTE: Refer to the fuse and relay map on the inner
surface of the cover of the IPM for A/C compressor
clutch relay identification and location.
(3) Remove the A/C compressor clutch 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 A/C compressor clutch relay identification
and location.
(1) Position the A/C compressor clutch relay into
the proper receptacle in the IPM.
(2) Align the A/C compressor clutch relay termi-
nals with the terminal cavities in the IPM receptacle.
(3) Push down firmly on the A/C compressor clutch
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.
A/C HEATER CONTROL
DESCRIPTION
The A/C-heater control is located at the center of
the instrument panel and uses electrical controls.
These controls provide the vehicle operator with a
number of setting options to help control the climate
and comfort within the vehicle. Refer to the owner's
manual in the vehicle glove box for more information
on the suggested operation and use of these controls.
The A/C-heater control cannot be repaired. If faulty
or damaged, the entire unit must be replaced. The
control knobs are available for service replacement.
STANDARD PROCEDURE
A/C-HEATER CONTROL CALIBRATION
The A/C-heater control module must be recali-
brated each time an actuator motor or the control
module is replaced. If the vehicle is so equipped, the
calibration procedure also includes rear HVAC posi-
tions for each actuator motor.
(1) Turn the ignition switch to the On position.
(2) If equipped with the manual temperature con-
trol (MTC) system, press and hold the Rear Wipe/
Wash and Recirculation buttoms for at least five
seconds. If equipped with the automatic temperature
control (ATC) systen, simultaneously press and hold
the Power and Recirculation buttons on the A/C-
heater control for at least five seconds. The MTC
A/C-heater control Rear Wipe/Wash Light Emitting
Diode (LED) and Recirculation LED, or the ATC A/C-
heater control Delay and Recirculation graphics will
begin to flash when the calibration procedure has
begun.
(3) The calibration procedure should take less than
two minutes to complete for the manual A/C-heater
control, and less than twenty seconds for the ATC
A/C-heater control. When the LEDs or graphics stop
flashing, the calibration procedure is complete.
(4) If the LEDs or graphics continue to flash
beyond the two minute (manual) or twenty second
(ATC) calibration time, it indicates that the A/C-
heater control has detected a failure and a Diagnostic
Trouble Code (DTC) has been set. Refer to Body
Diagnostic Procedures to perform further diagnosis.
The LEDs or graphics will continue to flash even
after the ignition switch is cycled Off and On, until a
successful calibration is completed or until the vehi-
cle has been driven about 13 kilometers (8 miles).
Fig. 8 A/C Compressor Clutch Relay
1 - INTEGRATED POWER MODULE (IPM)
2 - A/C COMPRESSOR CLUTCH RELAY
3 - FRONT CONTROL MODULE
RSCONTROLS - FRONT24-19
A/C COMPRESSOR CLUTCH RELAY (Continued)

(3) Connect the HVAC wire harness connector to
the blend 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 battery negative cable.
(6) Perform the heater-A/C 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).
BLOWER MOTOR RELAY
DESCRIPTION
The front blower motor relay is an International
Standards Organization (ISO)-type relay (Fig. 12).
Relays conforming to the ISO specifications have
common physical dimensions, current capacities, ter-
minal patterns, and terminal functions. The front
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 front blower motor relay identification
and location.
The black, molded plastic case is the most visible
component of the front 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 ismolded 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 front blower motor relay cannot be adjusted or
repaired. If the relay is damaged or faulty, it must be
replaced.
OPERATION
The blower motor relay is an electromechanical
switch that uses a low current input from the Front
Control Module (FCM) to control the high current
output to the blower motor resistor (manual heater-
A/C control) or blower power module (ATC control).
The movable common feed contact point is held
against the fixed normally closed contact point by
spring pressure. When the relay coil is energized, an
electromagnetic field is produced by the coil wind-
ings. 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 interfer-
ence that can be generated as the electromagnetic
field of the relay coil collapses.
Fig. 11 Blend 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)
Fig. 12 Front Blower Motor Relay
RSCONTROLS - FRONT24-23
BLEND DOOR ACTUATOR (Continued)

The blower motor relay terminals are connected to
the vehicle electrical system through a receptacle in
the Integrated Power Module (IPM). The inputs and
outputs of the 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
(automatic heater-A/C control) through a fuse in the
IPM on the fused front blower motor relay output cir-
cuit only when the blower motor relay coil is ener-
gized.
²The normally closed terminal (87A) is not con-
nected to any circuit in this application, but provides
a battery current output only when the 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. 13).
NOTE: Refer to the fuse and relay map on the inner
surface of the cover of the IPM for front blower
motor relay identification and location.
(3) Remove the front 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 front blower motor relay identification and
location.
(1) Position the front blower motor relay to the
proper receptacle in the IPM.
(2) Align the front blower motor relay terminals
with the terminal cavities in the IPM receptacle.
(3) Push down firmly on the front 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 blower motor resistor is used on this model when
it is equipped with the manual heater-A/C system.
Models equipped with the optional Automatic Tem-
perature Control (ATC) system use a blower power
module, instead of the blower motor resistor block
(Refer to 24 - HEATING & AIR CONDITIONING/
CONTROLS/POWER MODULE - DESCRIPTION).
The blower motor resistor block is mounted to the
rear of the HVAC housing, directly behind the glove
box opening in the instrument panel. The resistor
block consists of a molded plastic mounting plate
with two integral connector receptacles. Concealed
behind the mounting plate are four coiled resistor
wires contained within a protective stamped steel
cage. The blower motor resistor block is accessed for
service by removing the glove box from the instru-
ment panel.
OPERATION
The blower motor resistor block is connected to the
vehicle electrical system through a dedicated take
out and connector of the instrument panel wire har-
ness. A second connector receptacle receives the pig-
tail wire connector from the blower motor. The
blower motor resistor has multiple resistor wires,
Fig. 13 Front Blower Motor Relay
1 - INTEGRATED POWER MODULE (IPM)
2 - FRONT BLOWER MOTOR RELAY
2 - FRONT CONTROL MODULE (FCM)
24 - 24 CONTROLS - FRONTRS
BLOWER MOTOR RELAY (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)