Fuse for ac compressor CHRYSLER TOWN AND COUNTRY 2002 Service Manual

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.
IDLE AIR CONTROL MOTOR
DESCRIPTION
The idle air control motor is mounted on the throt-
tle body. The PCM operates the idle air control motor
(Fig. 14) or (Fig. 15).
OPERATION
The PCM adjusts engine idle speed through the
idle air control motor to compensate for engine load,
coolant temperature or barometric pressure changes.
The throttle body has an air bypass passage that
provides air for the engine during closed throttle idle.
The idle air control motor pintle protrudes into the
air bypass passage and regulates air flow through it.
The PCM adjusts engine idle speed by moving the
IAC motor pintle in and out of the bypass passage. The
adjustments are based on inputs the PCM receives.
The inputs are from the throttle position sensor, crank-
shaft position sensor, coolant temperature sensor, MAP
sensor, vehicle speed sensor and various switch opera-
tions (brake, park/neutral, air conditioning).
When engine rpm is above idle speed, the IAC is
used for the following functions:
²Off-idle dashpot
²Deceleration air flow control
²A/C compressor load control (also opens the pas-
sage slightly before the compressor is engaged so
that the engine rpm does not dip down when the
compressor engages)
Target Idle
Target idle is determined by the following inputs:
²Gear position
²ECT Sensor
²Battery voltage
²Ambient/Battery Temperature Sensor
²VSS
²TPS
²MAP Sensor
Fig. 14 TPS/IAC 2.4L
1 - Idle Air Control Motor
2 - Throttle Position Sensor
Fig. 15 TPS/IAC 3.3/3.8L
1 - Idle Air Control Motor
2 - Throttle Position Sensor
RSFUEL INJECTION14-27
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(2) If the a/c compressor clutch still will not
engage, disconnect the headlamp and dash wire har-
ness connector for the A/C pressure transducer and
check for battery current at the connector with the
engine running and the heater-A/C control set to the
A/C mode. If OK, go to TESTS . If not OK, use a
DRBIIItscan tool to perform further diagnosis. Refer
to the appropriate diagnostic information.
TESTS
(1) Verify the battery state of charge. (Refer to 8 -
ELECTRICAL/BATTERY SYSTEM/BATTERY -
DIAGNOSIS AND TESTING).
(2) Connect an ammeter (0 to 10 ampere scale
selected) in series with the clutch coil feed terminal.
Connect a voltmeter (0 to 20 volt scale selected) to
measure voltage across the battery and the clutch
coil.
(3) With the heater-A/C control in the A/C mode
and the blower at low speed, start the engine and
allow it to run at a normal idle speed.
(4) The compressor clutch should engage immedi-
ately, and the clutch coil voltage should be within
two volts of the battery voltage. If the coil voltage is
not within two volts of battery voltage, test the
clutch coil feed circuit for excessive voltage drop. If
the compressor clutch does not engage, use a
DRBIIItscan tool to perform further diagnosis. Refer
to the appropriate diagnostic information.
(5) With the ambient temperature at 21É C (70É F),
the compressor clutch coil is acceptable if the current
draw is 2.0 to 3.7 amperes at 11.5 to 12.5 volts at the
clutch coil. If the voltage is more than 12.5 volts, add
electrical loads by turning on electrical accessories
until the voltage reads below 12.5 volts.
(a) If the compressor clutch coil current reading
is zero, the coil is open and must be replaced.
(b) If the compressor clutch coil current reading
is four amperes or more, the coil is shorted and
must be replaced.
COMPRESSOR CLUTCH RELAY
DESCRIPTION
The compressor clutch relay (Fig. 17) is a Interna-
tional Standards Organization (ISO) micro-relay.
Relays conforming to the ISO specifications have
common physical dimensions, current capacities, ter-
minal patterns, and terminal functions. The ISO
micro-relay terminal functions are the same as a con-
ventional ISO relay. However, the ISO micro-relay
terminal pattern (or footprint) is different, the cur-
rent capacity is lower, and the physical dimensions
are smaller than those of the conventional ISO relay.
The compressor clutch relay is located in the Intelli-gent Power Module (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 compressor clutch relay identification and
location.
The black, molded plastic case is the most visible
component of the compressor clutch 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.
OPERATION
The compressor clutch relay is an electromechani-
cal switch that uses a low current input from the
Powertrain Control Module (PCM) to control the high
current output to the compressor clutch electromag-
netic coil. 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.
The compressor clutch relay terminals are con-
nected to the vehicle electrical system through a
receptacle in the Intelligent Power Module (IPM).
The inputs and outputs of the 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
RSCONTROLS - FRONT24-21
COMPRESSOR CLUTCH COIL (Continued)
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a battery current output only when the compressor
clutch relay coil is de-energized.
Refer to the appropriate wiring information. The
wiring information includes wiring diagrams, proper
wire and connector repair procedures, further details
on wire harness routing and retention, as well as
pin-out and location views for the various wire har-
ness connectors, splices, and grounds.
DIAGNOSIS AND TESTING - COMPRESSOR
CLUTCH RELAY
The compressor clutch relay (Fig. 17) is located in
the Intelligent Power Module (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 compressor clutch relay identifi-
cation and location. Remove the relay from the IPM
to perform the following tests:
(1) A relay in the de-energized position should
have continuity between terminals 87A and 30, and
no continuity between terminals 87 and 30. If OK, go
to Step 2. If not OK, replace the faulty relay.
(2) Resistance between terminals 85 and 86 (elec-
tromagnet) should be 75   5 ohms. If OK, go to Step
3. If not OK, replace the faulty relay.
(3) Connect a battery to terminals 85 and 86.
There should now be continuity between terminals
30 and 87, and no continuity between terminals 87A
and 30. If OK, use a DRBIIItscan tool to perform
further diagnosis of the relay circuits. Refer to the
appropriate diagnostic information. If not OK,
replace the faulty relay.
TERMINAL LEGEND
NUMBER IDENTIFICATION
30 COMMON FEED
85 COIL GROUND
86 COIL BATTERY
87 NORMALLY OPEN
87A NORMALLY CLOSED
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Unlatch and remove the cover from the Intelli-
gent Power Module (IPM).
(3) See the fuse and relay layout map molded into
the inner surface of the IPM cover for compressor
clutch relay identification and location.
(4) Remove the compressor clutch relay from the
IPM by pulling it straight up.
INSTALLATION
(1) See the fuse and relay layout map molded into
the inner surface of the Intelligent Power Module
(IPM) cover for compressor clutch relay identification
and location.
(2) Position the compressor clutch relay to the
proper receptacle in the IPM.
(3) Align the compressor clutch relay terminals
with the terminal cavities in the IPM relay recepta-
cle.
(4) Push down firmly on the compressor clutch
relay until the terminals are fully seated in the ter-
minal cavities in the IPM receptacle.
(5) Install and latch the cover onto the IPM.
(6) Reconnect the battery negative cable.
EVAPORATOR TEMPERATURE
SENSOR
DESCRIPTION
The evaporator temperature sensor is a switch that
is installed on the top of the expansion valve in the
right rear corner of the engine compartment (Fig.
18). The sensor has a small probe that is inserted in
a small well in the body of the expansion valve that
is filled with a special silicone-based thermal grease.
A small molded plastic push-in retainer secures the
sensor to a threaded hole in the top surface of the
expansion valve. Two terminals within a molded
plastic connector receptacle on the sensor connect it
to the vehicle electrical system through a take out
and connector of the HVAC wire harness.
Fig. 17 Compressor Clutch Relay
24 - 22 CONTROLS - FRONTRS
COMPRESSOR CLUTCH RELAY (Continued)
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quarter inner panel. Tighten the screw to 11 N´m (97
in. lbs.).
(7) Install and tighten the screw that secures the
back of the rear heater-A/C unit housing to the right
D-pillar. Tighten the screw to 11 N´m (97 in. lbs.).
(8) Install and tighten the two screws that secure
the top of the quarter trim panel attaching bracket to
the quarter inner panel. Tighten the screws to 1.7
N´m (15 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
TERMINAL LEGEND
NUMBER IDENTIFICATION
30 COMMON FEED
85 COIL GROUND
86 COIL BATTERY
87 NORMALLY OPEN
87A NORMALLY CLOSED
The blower motor relay (Fig. 5) is a International
Standards Organization (ISO) mini-relay. Relays con-
forming to the ISO specifications have common phys-
ical dimensions, current capacities, terminalpatterns, 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 blower
motor relay is located in the Intelligent 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
compressor clutch 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 factory-installed 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 (automatic heat-
er-A/C control). 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.
Fig. 5 Blower Motor Relay
24 - 32 CONTROLS - REARRS
BLEND DOOR ACTUATOR (Continued)
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The blower motor relay terminals are connected to
the vehicle electrical system through a receptacle in
the Intelligent Power Module (IPM). The inputs and
outputs of the compressor clutch 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 rear 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. The
wiring information includes wiring diagrams, proper
wire and connector repair procedures, further details
on wire harness routing and retention, as well as
pin-out and location views for the various wire har-
ness connectors, splices, and grounds.
DIAGNOSIS AND TESTING - BLOWER MOTOR
RELAY
The rear blower motor relay (Fig. 6) is located in
the Intelligent Power Module (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 identi-
fication and location. Remove the relay from the IPM
to perform the following tests:
(1) A relay in the de-energized position should
have continuity between terminals 87A and 30, and
no continuity between terminals 87 and 30. If OK, go
to Step 2. If not OK, replace the faulty relay.
(2) Resistance between terminals 85 and 86 (elec-
tromagnet) should be 75   5 ohms. If OK, go to Step
3. If not OK, replace the faulty relay.
(3) Connect a battery to terminals 85 and 86.
There should now be continuity between terminals
30 and 87, and no continuity between terminals 87A
and 30. If OK, use a DRBIIItscan tool to perform
further diagnosis of the relay circuits. Refer to the
appropriate diagnostic information. If not OK,
replace the faulty relay.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Unlatch and remove the cover from the Intelli-
gent Power Module (IPM) (Fig. 7).
Fig. 6 Blower Motor Relay
NUMBER IDENTIFICATION
30 COMMON FEED
85 COIL GROUND
86 COIL GROUND
87 NORMALLY OPEN
87A NORMALLY CLOSED
Fig. 7 Intelligent Power Module
1 - BATTERY THERMAL GUARD
2 - INTELLIGENT POWER MODULE
3 - FRONT CONTROL MODULE
RSCONTROLS - REAR24-33
BLOWER MOTOR RELAY (Continued)
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