sensor CHRYSLER VOYAGER 2002 Service Manual

INFRARED TEMPERATURE
SENSOR
DESCRIPTION
The rear infrared temperature sensor consists of
an infrared transducer that is concealed behind the
lens of the rear heater-A/C control in the headliner.
This sensor is used only on models equipped with the
optional Automatic Temperature Control (ATC) heat-
ing and air conditioning system. The rear infrared
temperature sensor is integral to the rear heater-A/C
control. The infrared sensor cannot be adjusted or
repaired and, if faulty or damaged, the rear heater-
A/C control unit must be replaced.
OPERATION
The rear infrared temperature sensor provides an
independent measurement input to the Automatic
Temperature Control (ATC) heater-A/C control mod-
ule that indicates the surface temperature of the rear
seat occupants. By using a surface temperature mea-
surement, rather than an air temperature measure-
ment, the ATC system is able to adjust itself to the
comfort level as perceived by the occupant. This
allows the system to detect and compensate for other
ambient conditions affecting comfort levels, such as
solar heat gain or evaporative heat loss. The ATC
system logic responds to the infrared sensor input by
calculating and adjusting the air flow temperature
and air flow rate needed to properly obtain and
maintain the selected comfort level temperatures for
the rear seat occupants. The ATC heater-A/C control
module continually monitors the infrared sensor cir-
cuit, 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 the
appropriate diagnostic information.
MODE DOOR ACTUATOR
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 heater-A/C unit housing to the right D-pillar.(5) Remove the screw that secures the front of the
rear heater-A/C unit housing to the right quarter
inner panel.
(6) Carefully pull the top of the rear heater-A/C
unit housing away from the right quarter inner panel
far enough to reach between the rear heater-A/C unit
housing and the quarter inner panel to access the
mode door actuator (Fig. 10).
(7) Remove the two screws that secure the mode
door actuator to the rear heater-A/C unit housing.
(8) Pull the mode door actuator away from the
rear heater-A/C unit housing far enough to disengage
the actuator output shaft from the mode door link-
age.
(9) Raise the mode door actuator far enough to
access and disconnect the rear HVAC wire harness
connector for the actuator from the actuator connec-
tor receptacle.
Fig. 10 Blend Door Actuator
1 - SCREW (2)
2 - MODE DOOR ACTUATOR
3 - SCREW (2)
4 - CONNECTOR
5 - BLEND DOOR ACTUATOR
6 - CONNECTOR
24 - 36 CONTROLS - REARRS
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or damaged, the instrument panel top cover must be
replaced.
²Demister Outlets- There are two side window
demisters that aid in defogging and defrosting the
front door windows. One demister outlet is located at
each outboard end of the instrument panel top pad,
near the belt line at the A-pillars. The demister out-
lets can be removed from the top pad individually for
service replacement.
²Instrument Panel Outlets- There are five
panel outlets in the instrument panel, one located
near each outboard end of the instrument panel fac-
ing the rear of the vehicle, and three located near the
top of the instrument panel center bezel. On models
with manual temperature control, all five of these
outlets are fully adjustable. On models with Auto-
matic Temperature Control (ATC), the center outlet
in the center bezel has fixed vanes because it also
houses the remote infrared temperature sensors for
the front seat positions. The outboard outlets can be
removed individually for service replacement. The
center bezel outlets are serviced as a gang of three
outlets and, on models with ATC, also includes the
infrared sensors.
²Front Door Rear Outlets- A fully adjustable
outlet located at the rear of each front door trim
panel supplies only cooled air to the intermediate
seat passengers. Air is supplied to these outlets from
the instrument panel through ducts in the doors that
use molded seals at the instrument panel to prevent
air leakage. The door ducts are integral to the front
door trim panels. These outlets also incorporate a red
reflector to improve the safety and visibility of an
opened front door to traffic approaching the vehicle
from the rear at night. These outlets can be removed
from the door trim panels for service replacement.
²Front Floor Outlets- There are two front floor
outlets, one located above each side of the floor panel
center tunnel below the instrument panel. These out-
lets are integral to the front heater-A/C unit distri-
bution housing.
²Rear Floor Outlets- Wide rear floor outlets
located under each front seat have integral, fixed
directional dividers to distribute heated air across
the floor for intermediate seat passengers. These out-
lets are integral to the floor distribution ducts routed
under the front floor carpet from an outlet nozzle on
the bottom of the front heater-A/C unit distribution
housing.
REMOVAL
REMOVAL - CENTER BEZEL OUTLETS
The three outlets located near the top of the
instrument panel center bezel are serviced only as a
set of all three outlets. If the vehicle is equipped withthe optional Automatic Temperature Control (ATC)
system, the center outlet of the three has fixed vanes
and also houses the remote front infrared tempera-
ture sensors.
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 center bezel from the instrument
panel. (Refer to 23 - BODY/INSTRUMENT PANEL/
INSTRUMENT PANEL CENTER BEZEL - REMOV-
AL).
(3) Place the center bezel face down on a suitable
work surface. Be certain to take the proper precau-
tions to protect the face of the center bezel from cos-
metic damage.
(4) If the vehicle is equipped with the optional
ATC system, disconnect the ATC remote infrared
temperature sensor jumper harness from the sensor
connector receptacle located on the bottom of the cen-
ter outlet housing (Fig. 3).
(5) Remove the three screws that secure the bot-
tom of the outlet housing to the center bezel.
(6) Roll the bottom of the outlet housing upwards
towards the top of the center bezel far enough to dis-
engage the retainer features on the top of the outlet
housing from their receptacles at the top of the cen-
ter bezel.
(7) Remove the center bezel outlets and housing
from the center bezel as a unit.
REMOVAL - DEMISTER OUTLET
(1) Using a trim stick or another suitable wide
flat-bladed tool, gently pry the outer perimeter of the
demister outlet away from the instrument panel top
pad until the snap features on the outlet are released
(Fig. 4).
(2) Remove the demister outlet from the demister
duct opening in the instrument panel top pad.
REMOVAL - FRONT DOOR REAR OUTLET
(1) Disconnect and isolate the battery negative
cable.
RSDISTRIBUTION - FRONT24-41
AIR OUTLETS (Continued)
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INSTALLATION
INSTALLATION - CENTER BEZEL OUTLETS
(1) Position the center bezel outlets and housing
onto the center bezel as a unit.
(2) Engage the retainer features on the top of the
outlet housing with their receptacles at the top of the
center bezel, then roll the bottom of the outlet hous-
ing downwards towards the center bezel.
(3) Install and tighten the three screws that secure
the bottom of the outlet housing to the center bezel.
Tighten the screws to 2 N´m (17 in. lbs.).
(4) If the vehicle is equipped with the optional
ATC system, reconnect the ATC remote infrared tem-
perature sensor jumper harness to the sensor connec-
tor receptacle located on the bottom of the center
outlet housing.
(5) Reinstall the center bezel onto the instrument
panel. (Refer to 23 - BODY/INSTRUMENT PANEL/
INSTRUMENT PANEL CENTER BEZEL - INSTAL-
LATION).
(6) Reconnect the battery negative cable.
INSTALLATION - DEMISTER OUTLET
(1) Position the demister outlet over the demister
duct opening in the instrument panel top pad.
(2) Using hand pressure, press the demister outlet
firmly and evenly into the instrument panel top pad
opening until the snap features on the outlet are
fully engaged.
INSTALLATION - FRONT DOOR REAR OUTLET
(1) Position the front door rear outlet through the
outside of the front door trim panel outlet opening.
(2) While keeping the outlet aligned with the door
duct opening behind the trim panel, use hand pres-
sure to press the outlet firmly and evenly through
the outside of the front door trim panel outlet open-
ing until the four latch features (two top and two bot-
tom) that secure the outlet to the inside of the
opening are fully engaged.
(3) Reinstall the trim panel onto the front door
inner panel. (Refer to 23 - BODY/DOOR - FRONT/
TRIM PANEL - INSTALLATION).
(4) Reconnect the battery negative cable.
INSTALLATION - INSTRUMENT PANEL OUTLET
(1) Position the instrument panel outlet into the
panel duct opening in the instrument panel top pad.
(2) Using hand pressure, press the instrument
panel outlet firmly and evenly into the instrument
panel top pad opening until the snap features on the
outlet are fully engaged.
BLOWER MOTOR
DESCRIPTION
The blower motor is a 12-volt, Direct Current (DC)
motor with a squirrel cage-type blower wheel that is
secured to the blower motor shaft (Fig. 7). The
blower motor and wheel are located near the passen-
ger side end of the heater-A/C unit within the two
halves of the intake air housing in the passenger
compartment below the instrument panel. The
blower motor and blower motor wheel are a factory
balanced unit and cannot be adjusted or repaired. If
faulty or damaged, the blower motor and blower
wheel must be replaced as a unit.
OPERATION
The blower motor will operate whenever the igni-
tion switch is in the On position and the heater-A/C
control power is turned on. The blower motor can
only be turned off by turning off the power at the
heater-A/C control. The blower motor receives battery
current whenever the front blower motor relay is
energized. The front blower motor relay output cir-
cuit is protected by a fuse in the Intelligent Power
Module (IPM) located in the engine compartment
near the battery. In the Manual system, the blower
motor speed is controlled by regulating the path to
ground through the blower control switch and the
blower motor resistor. In the ATC system, the blower
motor speed is controlled by an electronic blower
power module, which uses a pulse width modulated
input from the ATC module and feedback from the
blower motor to regulate the blower motor ground
Fig. 7 Blower Motor
1 - BLOWER MOTOR
2 - RUBBER GROMMET
3 - BLOWER MOTOR CONNECTOR
4 - MOUNTING TABS
RSDISTRIBUTION - FRONT24-43
AIR OUTLETS (Continued)
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(15) Carefully separate and remove the upper half
of the evaporator housing from the lower half. Be cer-
tain not to lose the rubber grommet for the HVAC
wire harness evaporator temperature sensor take
out. This grommet is located on the inboard side of
the flange around the expansion valve/evaporator
tube opening on the dash panel side of the unit,
where it is captured in a notched area between the
upper and lower housing halves (Fig. 13).(16) Carefully lift the evaporator and its foam
wrap out of the lower half of the evaporator housing
as a unit. Be certain not to lose the clam shell type
rubber seal that is fitted to the evaporator inlet and
outlet tubes where they exit the evaporator housing.
INSTALLATION
NOTE: If the evaporator is being replaced, add 60
milliliters (2 fluid ounces) of refrigerant oil to the
refrigerant system. Use only refrigerant oil of the
type recommended for the compressor in the vehi-
cle.
(1) Carefully lower the evaporator and its foam
wrap into the lower half of the evaporator housing as
a unit. Be certain that the clam shell type rubber
seal is fitted to the evaporator inlet and outlet tubes
where they exit the evaporator housing.
(2) Position the upper half of the evaporator hous-
ing onto the lower half. Be certain that the rubber
grommet and the HVAC wire harness take out for
the evaporator temperature sensor are captured in
the notched area between the upper and lower hous-
ing halves.
(3) Install and tighten the twelve screws around
the perimeter of the evaporator housing that secure
the upper housing half to the lower half. Tighten the
screws to 2 N´m (18 in. lbs.).
(4) Position the upper half of the recirculation air
door onto the lower half of the door.
(5) Install and tighten the two screws that secure
the upper half of the recirculation air door to the
Fig. 11 Upper Intake Air Housing
1 - EVAPORATOR HOUSING
2- UPPER INTAKE AIR HOUSING
3 - RECIRCULATION AIR DOOR
4 - BLOWER WHEEL
Fig. 12 Recirculation Air Door
1 - EVAPORATOR HOUSING
2 - UPPER RECIRCULATION AIR DOOR
3 - LOWER INTAKE AIR HOUSING
Fig. 13 Evaporator Housing
1 - LOWER EVAPORATOR HOUSING
2 - UPPER EVAPORATOR HOUSING
3 - BLOWER WHEEL
4 - EVAPORATOR
24 - 70 PLUMBING - FRONTRS
EVAPORATOR (Continued)
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lower half of the door. Tighten the screws to 2 N´m
(18 in. lbs.).
(6) Position the upper intake air housing onto the
top of the evaporator housing over the recirculation
air door and the blower wheel housing. Be certain
that the upper pivot of the recirculation air door is
captured in the pivot receptacle of the upper intake
air housing.
(7) Install and tighten the three screws that secure
the upper intake air housing to the top of the out-
board end of the evaporator housing. Be certain not
to miss the screw located just inside the inboard side
of the fresh air intake opening. Tighten the screws to
2 N´m (18 in. lbs.).
(8) Install and tighten the two screws that secure
the upper intake air housing to the lower intake air
housing. Tighten the screws to 2 N´m (18 in. lbs.).
(9) Engage the two hook formations on the bottom
of the distribution housing in the two receptacles on
the evaporator housing.
(10) Roll the top of the distribution housing up
into position against the evaporator housing.
(11) Install and tighten the three screws from the
dash panel side of the unit that secure the top of the
distribution housing to the inboard end of the evapo-
rator housing. Tighten the screws to 2 N´m (18 in.
lbs.).
(12) Engage the HVAC wire harness in the routing
clips molded into the outside of the HVAC housing
components.
(13) Reconnect the HVAC wire harness connector
for the blower motor with the motor connector recep-
tacle on the bottom of the outboard end of the evap-
orator housing.
(14) Reinstall the expansion valve onto the evapo-
rator inlet and outlet tube fittings. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/EXPANSION VALVE - INSTALLATION).
(15) Install a new foam seal onto the HVAC hous-
ing seal flange around the fresh air inlet opening and
the expansion valve/evaporator tube opening on the
dash panel side of the unit.
(16) Reinstall the heater core tubes into the heater
core. (Refer to 24 - HEATING & AIR CONDITION-
ING/PLUMBING - FRONT/HEATER CORE -
INSTALLATION - HEATER CORE TUBES).
(17) Reinstall the HVAC unit housing into the
vehicle. (Refer to 24 - HEATING & AIR CONDI-
TIONING/DISTRIBUTION - FRONT/HVAC HOUS-
ING - INSTALLATION).
(18) Run the HVAC Control Actuator Calibration
procedure(Refer to 24 - HEATING & AIR CONDI-
TIONING - DIAGNOSIS AND TESTING)(Refer to 24
- HEATING & AIR CONDITIONING - DIAGNOSIS
AND TESTING).EXPANSION VALVE
DESCRIPTION
The front ªHº valve-type thermal expansion valve
(TXV) is located at the dash panel between the liquid
and suction lines, and the evaporator coil. The
assembly consists of an H-valve body and a thermal
sensor. High-pressure, low temperature liquid refrig-
erant from the liquid line passes through the expan-
sion valve orifice, converting it into a low-pressure,
low-temperature mixture of liquid and gas before it
enters the evaporator coil. The expansion valve is a
factory calibrated unit and cannot be adjusted or
repaired. If faulty or damaged, the expansion valve
must be replaced.
OPERATION
A mechanical sensor in the expansion valve control
head monitors the temperature and pressure of the
refrigerant leaving the evaporator coil through the
suction line, and adjusts the orifice size at the liquid
line to let the proper amount of refrigerant into the
evaporator coil to meet the vehicle cooling require-
ments. Controlling the refrigerant flow through the
evaporator ensures that none of the refrigerant leav-
ing the evaporator is still in a liquid state, which
could damage the compressor. The thermo sensor
measures refrigerant suction gas temperature which
is monitored by the a/c control assembly.
DIAGNOSIS AND TESTING - EXPANSION VALVE
WARNING: REFER TO THE APPLICABLE WARN-
INGS AND CAUTIONS FOR THIS SYSTEM BEFORE
PERFORMING THE FOLLOWING OPERATION.
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - FRONT - WARNING - A/C PLUMBING)
and (Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - FRONT - CAUTION - A/C PLUMBING).
NOTE: The expansion valve should only be tested
following testing of the compressor.
NOTE: Liquid CO is required to test the expansion
valve. This material is available from most welding
supply facilities. Liquid CO is also available from
companies which service and sell fire extinguish-
ers.
When testing the expansion valve, the work area
and the vehicle temperature must be 21É to 27É C
(70É to 85É F). To test the expansion valve:
(1) Connect a charging station or manifold gauge
set to the refrigerant system service ports. Verify the
refrigerant charge level.
RSPLUMBING - FRONT24-71
EVAPORATOR (Continued)
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(2) Close all doors, windows and vents to the pas-
senger compartment.
(3) Set the heater-air conditioner controls so that
the compressor is operating, the temperature control
is in the highest temperature position, the mode door
is directing the output to the floor outlets, and the
blower is operating at the highest speed setting.
(4) Start the engine and allow it to idle at 1000
rpm. After the engine has reached normal operating
temperature, allow the passenger compartment to
heat up. This will create the need for maximum
refrigerant flow into the evaporator.
(5) If the refrigerant charge is sufficient, the dis-
charge (high pressure) gauge should read 965 to 1655
kPa (140 to 240 psi). The suction (low pressure)
gauge should read 140 kPa to 207 kPa (20 psi to 30
psi). If OK, go to Step 6. If not OK, replace the faulty
expansion valve.
WARNING:
PROTECT THE SKIN AND EYES FROM EXPOSURE
TO LIQUID CO. PERSONAL INJURY CAN RESULT.
(6) If the suction (low pressure) gauge reads
within the specified range, freeze the expansion valve
control head for 30 seconds using liquid CO or
another suitable super-cold material.Do not spray
R-134a or R-12 refrigerant on the expansion
valve control head for this test.The suction (low
pressure) gauge reading should drop by 10 psi. If OK,
go to Step 7 If not OK, replace the faulty expansion
valve.
(7) Allow the expansion valve control head to thaw.
The suction (low pressure) gauge reading should sta-
bilize at 140 kPa to 240 kPa (20 psi to 30 psi). If not
OK, replace the faulty expansion valve.
(8) When expansion valve testing is complete, test
the overall air conditioner performance. (Refer to 24 -
HEATING & AIR CONDITIONING - DIAGNOSIS
AND TESTING - A/C PERFORMANCE TEST).
Remove all test equipment before returning the vehi-
cle to service.
REMOVAL
WARNING: REFER TO THE APPLICABLE WARN-
INGS AND CAUTIONS FOR THIS SYSTEM BEFORE
PERFORMING THE FOLLOWING OPERATION.
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - FRONT - WARNING - A/C PLUMBING)
and (Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - FRONT - CAUTION - A/C PLUMBING).
(1) Recover the refrigerant from the refrigerant
system. (Refer to 24 - HEATING & AIR CONDI-
TIONING/PLUMBING - FRONT/REFRIGERANT -STANDARD PROCEDURE - REFRIGERANT
RECOVERY).
(2) Disconnect and isolate the battery negative
cable.
(3) Remove the air cleaner housing from the right
side of the engine compartment.
(4) Disconnect the drain tube from the wiper mod-
ule drain on the right side of the engine compart-
ment.
(5) Disconnect the headlamp and dash wire har-
ness connector for the A/C pressure transducer from
the transducer on the front liquid line rear section
(Fig. 14).
(6) Remove the screw that secures the front liquid
line rear section fitting to the top of the filter-drier.
(7) Disconnect the liquid line fitting from the fil-
ter-drier outlet port.
(8) Remove the seal from the liquid line fitting and
discard.
(9) Install plugs in, or tape over the opened liquid
line fitting and the filter-drier outlet port.
(10) Remove the nut that secures the suction line
and liquid line fittings to the stud on the expansion
valve.
(11) Disconnect the suction line and liquid line fit-
tings from the expansion valve and move the lines
out of the way.
(12) Remove the seals from the suction line and
liquid line fittings and discard.
(13) Install plugs in, or tape over the opened suc-
tion line and liquid line fittings and both expansion
valve ports.
Fig. 14 Expansion Valve
1 - A/C PRESSURE TRANSDUCER
2 - EVAPORATOR TEMPERATURE SENSOR
3 - EXPANSION VALVE
4 - SUCTION LINE
5 - HIGH SIDE SERVICE PORT
6 - FRONT LIQUID LINE REAR SECTION
24 - 72 PLUMBING - FRONTRS
EXPANSION VALVE (Continued)
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(14) Remove the two screws that secure the expan-
sion valve to the evaporator tube tapping plate.
(15) Disconnect the HVAC wire harness connector
for the evaporator temperature sensor from the sen-
sor on the top of the expansion valve.
(16) Remove the expansion valve from the evapo-
rator inlet and outlet tube fittings.
(17) Remove the seals from the evaporator inlet
and outlet tube fittings and discard.
(18) Install plugs in, or tape over the opened evap-
orator inlet and outlet tube fittings and both expan-
sion valve ports.
INSTALLATION
(1) Remove the tape or plugs from the evaporator
inlet and outlet tube fittings and both ports on the
back of the expansion valve.
(2) Lubricate new rubber O-ring seals with clean
refrigerant oil and install them on the evaporator
inlet and outlet tube fittings.
(3) Position the expansion valve onto the evapora-
tor inlet and outlet tube fittings.
(4) Install and tighten the two screws that secure
the expansion valve to the evaporator tube tapping
plate plate. Tighten the screws to 11 N´m (97 in.
lbs.).
(5) Reconnect the HVAC wire harness connector
for the evaporator temperature sensor to the sensor
connector receptacle on the top of the expansion
valve.
(6) Remove the tape or plugs from the front liquid
line rear section and suction line fittings for the
expansion valve and both ports on the front of the
expansion valve.
(7) Lubricate new rubber O-ring seals with clean
refrigerant oil and install them on the front liquid
line rear section and suction line fittings for the
expansion valve.
(8) Reconnect the liquid line and suction line fit-
tings to the expansion valve.
(9) Install and tighten the nut that secures the
suction line and liquid line fittings to the stud on the
expansion valve. Tighten the nut to 23 N´m (17 ft.
lbs.).
(10) Remove the tape or plugs from the liquid line
rear section fitting for the filter-drier and the filter-
drier outlet port.
(11) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the liquid line fitting.
(12) Reconnect the liquid line fitting to the filter-
drier outlet port on the top of the filter-drier.
(13) Install and tighten the screw that secures the
liquid line fitting to the filter-drier. Tighten the screw
to 2 N´m (18 in. lbs.).(14) Reconnect the headlamp and dash wire har-
ness connector for the A/C pressure transducer to the
transducer on the front liquid line rear section.
(15) Reconnect the drain tube to the wiper module
drain on the right side of the engine compartment.
(16) Reinstall the air cleaner housing into the
right side of the engine compartment.
(17) Reconnect the battery negative cable.
(18) Evacuate the refrigerant system. (Refer to 24
- HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM EVACUATE).
(19) Charge the refrigerant system. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM CHARGE).
HEATER CORE
DESCRIPTION
The heater core is located in the distribution hous-
ing of the heater-A/C unit, under the instrument
panel. It is a heat exchanger made of rows of tubes
and fins. One end of the core is fitted with a molded
plastic tank that includes integral heater core inlet
and outlet ports. The removable heater core tubes
are held in place these ports by a sealing plate
secured with a screw to the heater core tank. This
removable heater core tube arrangement allows the
heater core to be serviced without removing the heat-
er-A/C unit housing from the vehicle. The heater core
cannot be repaired and, if faulty or damaged, it must
be replaced.
OPERATION
Engine coolant is circulated through heater hoses
to the heater core at all times. As the coolant flows
through the heater core, heat removed from the
engine is transferred to the heater core fins and
tubes. Air directed through the heater core picks up
the heat from the heater core fins. The blend air door
allows control of the heater output air temperature
by controlling how much of the air flowing through
the heater-A/C unit housing is directed through the
heater core.
RSPLUMBING - FRONT24-73
EXPANSION VALVE (Continued)
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OPERATION
A mechanical sensor in the expansion valve control
head monitors the temperature and pressure of the
refrigerant leaving the evaporator coil through the
suction line, and adjusts the orifice size at the liquid
line to let the proper amount of refrigerant into the
evaporator coil to meet the vehicle cooling require-
ments. Controlling the refrigerant flow through the
evaporator ensures that none of the refrigerant leav-
ing the evaporator is still in a liquid state, which
could damage the compressor.
DIAGNOSIS AND TESTING - EXPANSION VALVE
WARNING: REFER TO THE APPLICABLE WARN-
INGS AND CAUTIONS FOR THIS SYSTEM BEFORE
PERFORMING THE FOLLOWING OPERATION.
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - FRONT - WARNING - A/C PLUMBING)
and (Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - FRONT - CAUTION - A/C PLUMBING).
NOTE: The expansion valve should only be tested
following testing of the compressor.
NOTE: Liquid CO is required to test the expansion
valve. This material is available from most welding
supply facilities. Liquid CO is also available from
companies which service and sell fire extinguish-
ers.
When testing the expansion valve, the work area
and the vehicle temperature must be 21É to 27É C
(70É to 85É F). To test the expansion valve:
(1) Connect a charging station or manifold gauge
set to the refrigerant system service ports. Verify the
refrigerant charge level.
(2) Close all doors, windows and vents to the pas-
senger compartment.
(3) Set the heater-air conditioner controls so that
the compressor is operating, the temperature control
is in the highest temperature position, the mode door
is directing the output to the floor outlets, and the
blower is operating at the highest speed setting.
(4) Start the engine and allow it to idle at 1000
rpm. After the engine has reached normal operating
temperature, allow the passenger compartment to
heat up. This will create the need for maximum
refrigerant flow into the evaporator.
(5) If the refrigerant charge is sufficient, the dis-
charge (high pressure) gauge should read 965 to 1655
kPa (140 to 240 psi). The suction (low pressure)
gauge should read 140 kPa to 207 kPa (20 psi to 30
psi). If OK, go to Step 6. If not OK, replace the faulty
expansion valve.WARNING: PROTECT THE SKIN AND EYES FROM
EXPOSURE TO LIQUID CO. PERSONAL INJURY
CAN RESULT.
(6) If the suction (low pressure) gauge reads
within the specified range, freeze the expansion valve
control head for 30 seconds using liquid CO or
another suitable super-cold material.Do not spray
R-134a or R-12 refrigerant on the expansion
valve control head for this test.The suction (low
pressure) gauge reading should drop by 10 psi. If OK,
go to Step 7 If not OK, replace the faulty expansion
valve.
(7) Allow the expansion valve control head to thaw.
The suction (low pressure) gauge reading should sta-
bilize at 140 kPa to 240 kPa (20 psi to 30 psi). If not
OK, replace the faulty expansion valve.
(8) When expansion valve testing is complete, test
the overall air conditioner performance. (Refer to 24 -
HEATING & AIR CONDITIONING - DIAGNOSIS
AND TESTING - A/C PERFORMANCE TEST).
Remove all test equipment before returning the vehi-
cle to service.
REMOVAL
WARNING: REFER TO THE APPLICABLE WARN-
INGS AND CAUTIONS FOR THIS SYSTEM BEFORE
PERFORMING THE FOLLOWING OPERATION.
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - FRONT - WARNING - A/C PLUMBING),
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - FRONT - CAUTION - A/C PLUMBING),
and (Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - FRONT - WARNING - HEATER PLUMB-
ING).
(1) Remove the rear heater-A/C unit housing from
the vehicle. (Refer to 24 - HEATING & AIR CONDI-
TIONING/DISTRIBUTION - REAR/REAR HEATER-
A/C HOUSING - REMOVAL).
(2) Carefully remove the foam insulator wrap from
the rear expansion valve.
(3) Remove the rear evaporator line extension from
the expansion valve. (Refer to 24 - HEATING & AIR
CONDITIONING/PLUMBING - REAR/EVAPORA-
TOR - REMOVAL - EVAPORATOR LINE EXTEN-
SION).
(4) Remove the two screws that secure the expan-
sion valve to the evaporator tube sealing plate.
(5) Remove the expansion valve from the evapora-
tor tubes.
(6) Remove the seals from the evaporator tube fit-
tings and discard.
(7) Install plugs in, or tape over the opened evap-
orator tube fittings and both expansion valve ports.
24 - 100 PLUMBING - REARRS
EXPANSION VALVE (Continued)
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EMISSIONS CONTROL
TABLE OF CONTENTS
page page
EMISSIONS CONTROL
DESCRIPTION
DESCRIPTION - VEHICLE EMISSION
CONTROL INFORMATION LABEL..........1
DESCRIPTION - TRIP DEFINITION.........1
DESCRIPTION - MONITORED COMPONENT . 1
OPERATION - NON-MONITORED CIRCUITS . . 5
DESCRIPTION - MONITORED SYSTEMS....6DESCRIPTION - HIGH AND LOW LIMITS....9
OPERATION
OPERATION - SYSTEM..................9
DRB IIITSTATE DISPLAY TEST MODE.....10
EVAPORATIVE EMISSIONS................11
EXHAUST GAS RECIRCULATION...........20
ON-BOARD DIAGNOSTICS................24
EMISSIONS CONTROL
DESCRIPTION
DESCRIPTION - VEHICLE EMISSION CONTROL
INFORMATION LABEL
All models have a Vehicle Emission Control Infor-
mation (VECI) Label. Chrysler permanently attaches
the label in the engine compartment. It cannot be
removed without defacing information and destroying
the label.
The label contains the vehicle's emission specifica-
tions and vacuum hose routings. All hoses must be
connected and routed according to the label.
DESCRIPTION - TRIP DEFINITION
A ªTripº means vehicle operation (following an
engine-off period) of duration and driving mode such
that all components and systems are monitored at
least once by the diagnostic system. The monitors
must successfully pass before the PCM can verify
that a previously malfunctioning component is meet-
ing the normal operating conditions of that compo-
nent. For misfire or fuel system malfunction, the
MIL may be extinguished if the fault does not recur
when monitored during three subsequent sequential
driving cycles in which conditions are similar to
those under which the malfunction was first deter-
mined.
Anytime the MIL is illuminated, a DTC is stored.
The DTC can self erase only after the MIL has been
extinguished. Once the MIL is extinguished, the
PCM must pass the diagnostic test for the most
recent DTC for 40 warm-up cycles (80 warm-up
cycles for the Fuel System Monitor and the Misfire
Monitor). A warm-up cycle can best be described by
the following:
²The engine must be running²A rise of 40ÉF in engine temperature must occur
from the time when the engine was started
²
Engine coolant temperature must crossover 160ÉF
²A ªdriving cycleº that consists of engine start up
and engine shut off.
Once the above conditions occur, the PCM is con-
sidered to have passed a warm-up cycle. Due to the
conditions required to extinguish the MIL and erase
the DTC, it is most important that after a repair has
been made, all DTC's be erased and the repair veri-
fied by running 1±good trip.
DESCRIPTION - MONITORED COMPONENT
There are several components that will affect vehi-
cle emissions if they malfunction. If one of these com-
ponents malfunctions the Malfunction Indicator
Lamp (Check Engine) will illuminate.
Some of the component monitors are checking for
proper operation of the part. Electrically operated
components now have input (rationality) and output
(functionality) checks. Previously, a component like
the Throttle Position sensor (TPS) was checked by
the PCM for an open or shorted circuit. If one of
these conditions occurred, a DTC was set. Now there
is a check to ensure that the component is working.
This is done by watching for a TPS indication of a
greater or lesser throttle opening than MAP and
engine rpm indicate. In the case of the TPS, if engine
vacuum is low and engine rpm is 1600 or greater and
the TPS indicates a small throttle opening, a DTC
will be set. The same applies to low vacuum and
1600 rpm.
Any component that has an associated limp in will
set a fault after 1 trip with the malfunction present.
Refer to the Diagnostic Trouble Codes Description
Charts (Refer to 8 - ELECTRICAL/ELECTRONIC
CONTROL MODULES/POWERTRAIN CONTROL
MODULE - DESCRIPTION) and the appropriate
Powertrain Diagnostic Procedure Manual for diag-
nostic procedures.
RSEMISSIONS CONTROL25-1
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The following is a list of the monitored compo-
nents:
²Comprehensive Components
²Oxygen Sensor Monitor
²Oxygen Sensor Heater Monitor
²Catalyst Monitor
COMPREHENSIVE COMPONENTS
Along with the major monitors, OBD II requires
that the diagnostic system monitor any component
that could affect emissions levels. In many cases,
these components were being tested under OBD I.
The OBD I requirements focused mainly on testing
emissions-related components for electrical opens and
shorts.
However, OBD II also requires that inputs from
powertrain components to the PCM be tested for
rationality, and that outputs to powertrain compo-
nents from the PCM be tested forfunctionality.
Methods for monitoring the various Comprehensive
Component monitoring include:
(1) Circuit Continuity
²Open
²Shorted high
²Shorted to ground
(2) Rationality or Proper Functioning
²Inputs tested for rationality
²Outputs tested for functionality
NOTE: Comprehensive component monitors are
continuous. Therefore, enabling conditions do not
apply.
Input RationalityÐWhile input signals to the
PCM are constantly being monitored for electrical
opens and shorts, they are also tested for rationality.
This means that the input signal is compared against
other inputs and information to see if it makes sense
under the current conditions.
PCM sensor inputs that are checked for rationality
include:
²Manifold Absolute Pressure (MAP) Sensor
²Oxygen Sensor (O2S)
²Engine Coolant Temperature (ECT) Sensor
²Camshaft Position (CMP) Sensor
²Vehicle Speed Sensor
²Crankshaft Position (CKP) Sensor
²Intake/inlet Air Temperature (IAT) Sensor
²Throttle Position (TPS) Sensor
²Ambient/Battery Temperature Sensors
²Power Steering Switch
²Oxygen Sensor Heater
²Engine Controller
²Brake Switch
²Leak Detection Pump Switch (if equipped)
²P/N Switch
²Trans ControlsOutput FunctionalityÐPCM outputs are tested
for functionality in addition to testing for opens and
shorts. When the PCM provides a voltage to an out-
put component, it can verify that the command was
carried out by monitoring specific input signals for
expected changes. For example, when the PCM com-
mands the Idle Air Control (IAC) Motor to a specific
position under certain operating conditions, it expects
to see a specific (target) idle speed (RPM). If it does
not, it stores a DTC.
PCM outputs monitored for functionality include:
²Fuel Injectors
²Ignition Coils
²Torque Converter Clutch Solenoid
²Idle Air Control
²Purge Solenoid
²EGR Solenoid (if equipped)
²LDP Solenoid (if equipped)
²Radiator Fan Control
²Trans Controls
OXYGEN SENSOR (O2S) MONITOR
DESCRIPTIONÐEffective control of exhaust
emissions is achieved by an oxygen feedback system.
The most important element of the feedback system
is the O2S. The O2S is located in the exhaust path.
Once it reaches operating temperature 300É to 350ÉC
(572É to 662ÉF), the sensor generates a voltage that
is inversely proportional to the amount of oxygen in
the exhaust. When there is a large amount of oxygen
in the exhaust caused by a lean condition, the sensor
produces a low voltage, below 450 mV. When the oxy-
gen content is lower, caused by a rich condition, the
sensor produces a higher voltage, above 450mV.
The information obtained by the sensor is used to
calculate the fuel injector pulse width. The PCM is
programmed to maintain the optimum air/fuel ratio.
At this mixture ratio, the catalyst works best to
remove hydrocarbons (HC), carbon monoxide (CO)
and nitrous oxide (NOx) from the exhaust.
The O2S is also the main sensing element for the
EGR (if equipped), Catalyst and Fuel Monitors.
The O2S may fail in any or all of the following
manners:
²Slow response rate (Big Slope)
²Reduced output voltage (Half Cycle)
²Heater Performance
Slow Response Rate (Big Slope)ÐResponse rate
is the time required for the sensor to switch from
lean to rich signal output once it is exposed to a
richer than optimum A/F mixture or vice versa. As
the PCM adjusts the air/fuel ratio, the sensor must
be able to rapidly detect the change. As the sensor
ages, it could take longer to detect the changes in the
oxygen content of the exhaust gas. The rate of
change that an oxygen sensor experiences is called
25 - 2 EMISSIONS CONTROLRS
EMISSIONS CONTROL (Continued)
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