2005 CHRYSLER CARAVAN ECU

(15) If the vehicle is equipped with the optional
rear heating-A/C system, go to Step 16. If the vehicle
is not equipped with the optional rear heating-A/C
system, go to Step 22.
(16) Raise and support the vehicle.
(17) Cut the tie strap located just forward of the
connections between the underbody plumbing and
the engine compartment plumbing for the rear heat-
ing-A/C system (Fig. 29).
(18) Disconnect the A/C liquid line extension fit-
ting from the underbody liquid line fitting for the
rear A/C system.
(19) Remove the O-ring seal from the underbody
liquid line fitting and discard.
(20) Install plugs in, or tape over the opened liquid
line fittings.
(21) Lower the vehicle.
(22) Remove the rear section of the A/C liquid line
from the engine compartment.
INSTALLATION
FRONT SECTION
(1) Position the front section of the A/C liquid line
into the engine compartment.
(2) Remove the tape or plugs from the liquid line
fitting and the receiver/drier inlet port.
(3) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it onto the liquid line fit-
ting.
(4) Connect the A/C liquid line to the receiver/
drier.(5) Install the bolt that secures the A/C liquid line
to the receiver/drier. Tighten the bolt to 11 N´m (97
in. lbs.).
(6) Engage the retainer that secures the liquid line
routing clip to the top of the right frame rail ahead of
the front strut tower in the engine compartment.
(7) Remove the tape or plugs from the condenser
outlet port and the liquid line fitting.
(8) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it and a new gasket onto
the liquid line fitting.
(9) Connect the A/C liquid line to the A/C con-
denser.
(10) Install the nut that secures the A/C liquid line
to the A/C condenser. Tighten the nut to 23 N´m (17
ft. lbs.).
(11) Position the radiator sight shield onto the
radiator closure panel crossmember.
(12) Install the five small screws that secure the
front fascia grille inserts to the radiator sight shield.
Tighten the screws to 2 N´m (17 in. lbs.).
(13) Install the two large screws that secure the
front fascia and the outboard ends of the radiator
sight shield to the radiator closure panel crossmem-
ber. Tighten the screws to 6 N´m (53 in. lbs.).
(14) Reinstall the air cleaner housing into the
right side of the engine compartment.
(15) Reconnect the negative battery cable.
(16) Evacuate the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM EVACUATE).
(17) Charge the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM CHARGE).
REAR SECTION
(1) Position the rear section of the A/C liquid line
into the engine compartment.
(2) Remove the tape or plugs from the suction line
and liquid line fittings and both expansion valve
ports.
(3) Lubricate new rubber O-ring seals with clean
refrigerant oil and install them onto the suction line
and liquid line fittings.
(4) Reconnect the A/C liquid line and the A/C suc-
tion line to the A/C expansion valve.
(5) Install the nut that secures the rear section of
the A/C liquid line and the A/C suction line to the
A/C expansion valve. Tighten the nut to 23 N´m (17
ft. lbs.).
(6) Remove the tape or plugs from the liquid line
fitting and the receiver/drier outlet port.
Fig. 29 Underbody A/C Line Connections
1 - SUCTION LINE EXTENSION TUBE
2 - LIQUID LINE EXTENSION TUBE
3 - RETAINING STRAP
4 - REAR HEATER EXTENSION TUBES
5 - UNDERBODY REFRIGERANT LINES
RSPLUMBING - FRONT24-91
LIQUID LINE (Continued)

(7) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the liquid line fitting.
(8) Reconnect the A/C liquid line to the receiver/
drier.
(9) Install the bolt that secures the A/C liquid line
to the receiver/drier. Tighten the bolt to 11 N´m (97
in. lbs.).
(10) If equipped, reinstall the A/C ground strap
eyelet terminal connector onto the weld stud on the
top of the right front strut tower (if equipped).
(11) If equipped, install the nut that secures the
A/C ground strap to the weld stud. Tighten the nut
to 12 N´m (106 in. lbs.)
(12) Install the A/C pressure transducer (Refer to
24 - HEATING & AIR CONDITIONING/CONTROLS
- FRONT/A/C PRESSURE TRANSDUCER - INSTAL-
LATION).
(13) Connect the drain tube to the wiper module
drain on the right side of the engine compartment.
(14) Install the air cleaner housing into the right
side of the engine compartment.
(15) On RHD models, install the liquid line into
the retaining bracket located at the top of the dash
panel.
(16) If the vehicle is equipped with the optional
rear heating-A/C system, go to Step 17. If the vehicle
does not have the optional rear heating-A/C system,
go to Step 23.
(17) Raise and support the vehicle.
(18) Remove the tape or plugs from the A/C liquid
line extension fitting and the underbody liquid line
fitting.
(19) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the underbody liquid
line fitting.
(20) Connect the A/C liquid line extension fitting
to the underbody liquid line fitting. Tighten the fit-
tings to 23 N´m (17 ft. lbs.).
(21) Install a new tie strap just forward of the con-
nections between the underbody plumbing and the
engine compartment plumbing for the rear heating-
A/C system.
(22) Lower the vehicle.
(23) Reconnect the negative battery cable.
(24) Evacuate the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM EVACUATE).
(25) Charge the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM CHARGE).RECEIVER / DRIER
DESCRIPTION
The receiver/drier is mounted in a bracket secured
to the right front strut tower in the engine compart-
ment. The receiver/drier is connected between the
front and rear sections of the liquid line between the
condenser outlet and the evaporator inlet. The receiv-
er/drier cannot be repaired. If the receiver/drier is
faulty or damaged, or if the refrigerant system has
been contaminated or left open to the atmosphere for
an indeterminable period or if the A/C compressor
has failed, it must be replaced.
OPERATION
The receiver/drier performs a filtering action to
prevent foreign material in the refrigerant from con-
taminating the expansion valve. Desiccant inside the
receiver/drier canister absorbs any moisture which
may have entered and become trapped within the
refrigerant system. In addition, during periods of
high demand air conditioner operation, the receiver/
drier acts as a reservoir to store surplus refrigerant.
Refrigerant enters the receiver/drier as a high-pres-
sure, low temperature liquid.
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 CONDITION-
ING/PLUMBING - FRONT/REFRIGERANT - STAN-
DARD PROCEDURE - REFRIGERANT
RECOVERY).
(2) Remove the air cleaner housing from the right
side of the engine compartment.
(3) Remove the bolt that secures the liquid line
front section fitting to the top of the receiver/drier
(Fig. 30).
(4) Disconnect the liquid line fitting from the
receiver/drier inlet port.
(5) Remove the O-ring seal from the liquid line fit-
ting and discard.
(6) Install plugs in, or tape over the opened liquid
line fitting and the receiver/drier inlet port.
24 - 92 PLUMBING - FRONTRS
LIQUID LINE (Continued)

(7) Remove the bolt that secures the liquid line
rear section fitting to the top of the receiver/drier.
(8) Disconnect the liquid line fitting from the
receiver/drier outlet port.
(9) Remove the seal from the liquid line fitting and
discard.
(10) Install plugs in, or tape over the opened liquid
line fitting and the receiver/drier outlet port.
(11) Remove the two nuts that secure the receiver/
drier mounting bracket to the weld studs on the side
of the right front strut tower.
(12) Remove the receiver/drier and mounting
bracket unit from the studs.
INSTALLATION
NOTE: If the receiver/drier is being replaced, add 25
milliliters (0.8 fluid ounce) of refrigerant oil to the
refrigerant system. Use only refrigerant oil of the
type recommended for the A/C compressor in the
vehicle.(1) Position the receiver/drier and mounting
bracket unit onto the weld studs on the side of the
right front strut tower.
(2) Install the two nuts that secure the receiver/
drier mounting bracket to the studs. Tighten the
nuts to 10 N´m (89 in. lbs.).
(3) Remove the tape or plugs from the liquid line
rear section fitting for the receiver/drier and the
receiver/drier outlet port.
(4) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the liquid line fitting.
(5) Reconnect the liquid line fitting to the receiver/
drier outlet port on the top of the receiver/drier.
(6) Install the bolt that secures the liquid line fit-
ting to the receiver/drier. Tighten the bolt to 11 N´m
(97 in. lbs.).
(7) Remove the tape or plugs from the liquid line
front section fitting for the receiver/drier and the
receiver/drier inlet port.
(8) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the liquid line fitting.
(9) Reconnect the liquid line fitting to the receiver/
drier inlet port on the top of the receiver/drier.
(10) Install the bolt that secures the liquid line fit-
ting to the receiver/drier. Tighten the bolt to 11 N´m
(97 in. lbs.).
(11) Reinstall the air cleaner housing into the
right side of the engine compartment.
(12) Evacuate the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM EVACUATE).
(13) Charge the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM CHARGE).
REFRIGERANT
DESCRIPTION
The refrigerant used in this air conditioning sys-
tem is a HydroFluoroCarbon (HFC), type R-134a.
Unlike R-12, which is a ChloroFluoroCarbon (CFC),
R-134a refrigerant does not contain ozone-depleting
chlorine. R-134a refrigerant is a non-toxic, non-flam-
mable, clear, and colorless liquefied gas. Even though
R-134a does not contain chlorine, it must be
reclaimed and recycled just like CFC-type refriger-
ants. This is because R-134a is a greenhouse gas and
can contribute to global warming.
Fig. 30 Reciever/Drier - LHD Shown, RHD Typical
1 - A/C GROUND STRAP (IF EQUIPPED)
2 - NUT (IF EQUIPPED)
3 - WELD STUD (IF EQUIPPED)
4 - A/C PRESSURE TRANSDUCER
5 - WELD STUD (2)
6 - A/C EXPANSION VALVE
7 - A/C LIQUID LINE (REAR SECTION)
8 - LIQUID LINE EXTENSION (REAR A/C ONLY)
9 - NUT (2)
10 - RECEIVER/DRIER
11 - ROUTING CLIP
12 - A/C LIQUID LINE (FRONT SECTION)
RSPLUMBING - FRONT24-93
RECEIVER / DRIER (Continued)

CAUTION: A valve core that is not fully seated in
the A/C service port can result in damage to the
valve during refrigerant system evacuation and
charge. Such damage may result in a loss of sys-
tem refrigerant while uncoupling the charge adapt-
ers.
(4) Evacuate the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM EVACUATE).
(5) Charge the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM CHARGE).
(6) Reinstall the protective cap onto the A/C ser-
vice port.
SUCTION LINE
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).
NOTE: The front suction line includes the low side
service port on a section of tubing located near the
A/C compressor. On models equipped with the
optional rear A/C system, the front suction line also
includes a suction line hose and tube extension
that connects the front suction line to the suction
line for the rear A/C system.
(1) Recover the refrigerant from the refrigerant
system (Refer to 24 - HEATING & AIR CONDITION-
ING/PLUMBING - FRONT/REFRIGERANT - STAN-
DARD PROCEDURE - REFRIGERANT
RECOVERY).
(2) Disconnect and isolate the battery negative
cable.
(3) Remove the air cleaner top cover and snorkel
from the air cleaner housing located on 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) Remove the nut that secures the suction line
fitting to the top of the A/C compressor.
(6) Disconnect the suction line fitting from the
compressor suction port.(7) Remove the O-ring seal from the suction line
fitting and discard.
(8) Install plugs in, or tape over the opened suc-
tion line fitting and the compressor suction port.
(9) Remove the retainer that secures the suction
line routing clip to the receiver/drier mounting
bracket on the side of the right front strut tower in
the engine compartment (Fig. 31).
(10) Remove the nut that secures the suction line
and liquid line fittings to the expansion valve.
(11) Disconnect the suction line and liquid line fit-
tings from the expansion valve.
(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.
(14) Remove the suction line from the retaining
bracket located at the top of the dash panel.
(15) If the vehicle is equipped with the optional
rear air conditioner, go to Step 16. If the vehicle does
not have the optional rear air conditioner, go to Step
22.
(16) Raise and support the vehicle.
(17) Cut the tie strap located just forward of the
connections between the underbody plumbing and
the engine compartment plumbing for the rear
heater and air conditioner (Fig. 32).
Fig. 31 Suction Line - LHD Shown, RHD Typical
1 - A/C EXPANSION VALVE
2 - SUCTION LINE EXTENSION (REAR A/C ONLY)
3 - NUT
4 - RETAINING CLIP
5 - SUCTION LINE
24 - 96 PLUMBING - FRONTRS
SERVICE PORT VALVE CORE (Continued)

(18) Disconnect the suction line extension fitting
from the underbody suction line fitting for the rear
air conditioner.
(19) Remove the O-ring seal from the underbody
suction line fitting and discard.
(20) Install plugs in, or tape over the opened suc-
tion line fittings.
(21) Lower the vehicle.
(22) Remove the suction line from the engine com-
partment.
INSTALLATION
(1) Position the suction line into the engine com-
partment.
(2) Remove the tape or plugs from the suction line
and liquid line fittings and both expansion valve
ports.
(3) Lubricate new rubber O-ring seals with clean
refrigerant oil and install them on the suction line
and liquid line fittings.
(4) Reconnect the liquid line and suction line fit-
tings to the expansion valve.
(5) Install the nut that secures the suction line
and liquid line fittings to the expansion valve.
Tighten the nut to 23 N´m (17 ft. lbs.).
(6) Install the retainer that secures the suction
line routing clip to the receiver/drier mounting
bracket on the side of the right front strut tower in
the engine compartment.(7) Remove the tape or plugs from the compressor
suction port and the suction line fitting.
(8) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the suction line fit-
ting.
(9) Install a new dual plan seal and reconnect the
suction line fitting to the compressor suction port.
(10) Install the nut that secures the suction line
fitting to the A/C compressor. Tighten the nut to 23
N´m (17 ft. lbs.).
(11) Reconnect the drain tube to the wiper module
drain on the right side of the engine compartment.
(12) Install the air cleaner top cover and snorkel
onto the air cleaner housing located on the right side
of the engine compartment.
(13) On RHD models, install the suction line into
the retaining bracket located at the top of the dash
panel.
(14) If the vehicle is equipped with the optional
rear air conditioner, go to Step 15. If the vehicle does
not have the optional rear air conditioner, go to Step
21.
(15) Raise and support the vehicle.
(16) Remove the tape or plugs from the suction
line extension fitting and the underbody suction line
fitting.
(17) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the underbody suction
line fitting.
(18) Reconnect the suction line extension fitting to
the underbody suction line fitting. Tighten the fit-
tings to 23 N´m (17 ft. lbs.).
(19) Install a new tie strap just forward of the con-
nections between the underbody plumbing and the
engine compartment plumbing for the rear heater
and air conditioner.
(20) Lower the vehicle.
(21) Reconnect the battery negative cable.
(22) Evacuate the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM EVACUATE).
(23) Charge the refrigerant system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM CHARGE).
Fig. 32 Underbody A/C Line Connections
1 - SUCTION LINE EXTENSION TUBE
2 - LIQUID LINE EXTENSION TUBE
3 - RETAINING STRAP
4 - REAR HEATER EXTENSION TUBES
5 - UNDERBODY REFRIGERANT LINES
RSPLUMBING - FRONT24-97
SUCTION LINE (Continued)

TIONING/PLUMBING - REAR/EXPANSION VALVE
- REMOVAL).
(4) Remove the rubber grommet that seals the
evaporator inlet and outlet tubes to the rear HVAC
housing near the expansion valve.
(5) Remove the three screws that secure the upper
half of the rear HVAC housing to the lower half (Fig.
1).
(6) Remove the three metal spring clips that
secure the upper half of the rear HVAC housing to
the lower half.
(7) Carefully separate and remove the upper half
of the rear HVAC housing from the lower half.
(8) Remove the A/C evaporator from the lower half
of the rear HVAC housing.
REAR A/C EVAPORATOR LINE EXTENSION
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 PLUMBING).
(1) Remove the rear HVAC housing from the vehi-
cle (Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION/HVAC HOUSING - REMOVAL).
(2) Remove the screw that secures the plate that
captures and seals the evaporator line extension
within the base of the rear HVAC housing (Fig. 2).
(3) Remove the capture plate from the rear HVAC
housing base.(4) Carefully peel back the expansion valve foam
insulator wrap far enough to access the evaporator
line extension sealing plate on the bottom of the
expansion valve (Fig. 3).
(5) Remove the two screws that secure the expan-
sion valve bracket to the lower rear HVAC housing.
(6) Remove the nut that secures the expansion
valve bracket to the expansion valve stud.
(7) Remove the expansion valve bracket from the
expansion valve stud.
(8) Remove the nut that secures the evaporator
line extension seal plate to the expansion valve stud.
Fig. 1 Rear A/C Evaporator
1 - UPPER REAR HVAC HOUSING
2 - REAR A/C EVAPORATOR
3 - LOWER REAR HVAC HOUSING
Fig. 2 Evaporator Line Extension Plate
1 - REAR HVAC HOUSING BASE
2 - PLATE
3 - EVAPORATOR LINE EXTENSION
Fig. 3 Rear A/C Evaporator Line Extension
1 - UPPER REAR HVAC HOUSING
2 - LOWER REAR HVAC HOUSING
3 - EXPANSION VALVE BRACKET
4 - EVAPORATOR LINE EXTENSION
5 - EXPANSION VALVE STUD
6 - INSULATOR WRAP
RSPLUMBING - REAR24-99
A/C EVAPORATOR (Continued)

(9) Remove the evaporator line extension seal
plate from the expansion valve stud.
(10) Remove the evaporator line extension from
the expansion valve and the rear HVAC housing
base.
(11) Remove the seals from the evaporator line
extension fittings and discard.
(12) Install plugs in, or tape over the opened evap-
orator line extension fittings and both expansion
valve ports.
INSTALLATION
REAR A/C EVAPORATOR
NOTE: If the rear A/C evaporator is being replaced,
add 50 milliliters (1.7 fluid ounces) of refrigerant oil
to the refrigerant system. Use only refrigerant oil of
the type recommended for the A/C compressor in
the vehicle.
(1) Carefully lower the rear A/C evaporator and its
foam wrap into the lower half of the rear HVAC
housing.
(2) Position the upper half of the rear HVAC hous-
ing onto the lower half.
(3) Install the three metal spring clips that secure
the upper half of the rear HVAC housing to the lower
half.
(4) Install the three screws that secure the upper
half of the rear HVAC housing to the lower half.
Tighten the screws to 2 N´m (17 in. lbs.).
(5) Install the rubber grommet that seals the evap-
orator inlet and outlet tubes to the rear HVAC hous-
ing near the expansion valve.
(6) Reinstall the rear expansion valve onto the
rear A/C evaporator (Refer to 24 - HEATING & AIR
CONDITIONING/PLUMBING - REAR/EXPANSION
VALVE - INSTALLATION).
(7) Reinstall the rear evaporator extension line
onto the expansion valve (Refer to 24 - HEATING &
AIR CONDITIONING/PLUMBING - REAR/EVAPO-
RATOR - INSTALLATION - EVAPORATOR EXTEN-
SION LINE).
(8) Reinstall the rear HVAC housing into the vehi-
cle (Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION - REAR/REAR HEATER-A/C
HOUSING - INSTALLATION).
REAR A/C EVAPORATOR LINE EXTENSION
(1) Remove the tape or plugs from the evaporator
line extension fittings and both expansion valve
ports.
(2) Lubricate new rubber O-ring seals with clean
refrigerant oil and install them on the evaporator
line extension fittings.(3) Position the evaporator line extension to the
expansion valve and the rear HVAC housing base.
(4) Position the evaporator line extension seal
plate over the expansion valve stud.
(5) Install the nut that secures the evaporator line
extension seal plate to the expansion valve stud.
Tighten the nut to 23 N´m (17 ft. lbs.).
(6) Position the expansion valve bracket over the
expansion valve stud.
(7) Install the two screws that secure the expan-
sion valve bracket to the lower rear HVAC housing.
Tighten the screws to 2 N´m (17 in. lbs.).
(8) Install the nut that secures the expansion
valve bracket to the expansion valve stud. Tighten
the nut to 23 N´m (17 ft. lbs.).
(9) Carefully restore the expansion valve foam
insulator wrap back around the expansion valve.
(10) Position the plate that captures and seals the
evaporator line extension onto the rear HVAC hous-
ing base.
(11) Install the screw that secures the capture
plate to the base of the rear HVAC housing. Tighten
the screw to 2 N´m (17 in. lbs.).
(12) Install the rear HVAC housing into the vehi-
cle (Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION/HVAC HOUSING -
INSTALLATION).
A/C EXPANSION VALVE
DESCRIPTION
The rear ªHº valve-type thermal expansion valve
(TXV) is located at the rear of the rear HVAC hous-
ing between the evaporator line extension and the
evaporator coil. High-pressure, low temperature liq-
uid refrigerant from the liquid line passes through
the expansion valve orifice, converting it into a low-
pressure, low-temperature mixture of liquid and gas
before it enters the evaporator coil.
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 rear A/C expansion valve cannot be adjusted
or repaired and, if faulty or damaged, it must be
replaced.
24 - 100 PLUMBING - REARRS
A/C EVAPORATOR (Continued)

DIAGNOSIS AND TESTING
REAR A/C 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
2is required to test the expansion
valve. This material is available from most welding
supply facilities. Liquid CO
2is 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
2. 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
2or another suit-
able super-cold material.Do not spray R-134a or
R-12 refrigerant on the expansion valve controlhead 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 PLUMBING).
(1) Remove the rear HVAC housing from the vehi-
cle (Refer to 24 - HEATING & AIR CONDITIONING/
DISTRIBUTION/HVAC 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.
INSTALLATION
(1) Remove the tape or plugs from the rear A/C
evaporator tube fittings and both expansion valve
ports.
(2) Lubricate new rubber O-ring seals with clean
refrigerant oil and install them on the rear evapora-
tor tube fittings.
(3) Position the expansion valve onto the evapora-
tor tubes.
(4) Install the two screws that secure the rear A/C
expansion valve to the evaporator tube sealing plate.
Tighten the screws to 11 N´m (97 in. lbs.).
RSPLUMBING - REAR24 - 101
A/C EXPANSION VALVE (Continued)