2001 DODGE TOWN AND COUNTRY ECO mode

it is engaged on the nipple and peel the hose off of
the nipple. This method of removal will require
heater hose replacement.
INSTALLATION
There are several heater core plumbing configura-
tions used on this model, depending upon the engine
size and other optional equipment. One plumbing
configuration is used for all 2.4L engines (Fig. 21),
while the 3.3L and 3.8L engines have unique heater
return plumbing on the engine for models with or
without an optional engine oil cooler (Fig. 24) or (Fig.
25). There are also unique plumbing configurations
at the heater core for models with or without the
optional rear heater and air conditioner (Fig. 22) or
(Fig. 23). All models use a combination of formed
steel tubing and rubber hoses. In most cases, the
rubber hose is secured to the steel tubing with a
spring tension clamp.
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 - HEATER PLUMB-
ING).
(1) Using spring tension clamp pliers, compress
and slide the clamps that secure each end of the
heater hose toward the center of the hose being
installed. Release the clamp when it is near the cen-
ter of the hose.(2) Grasp one end of the heater hose being
installed firmly and carefully twist the hose back and
forth while pushing it over from the barbed end of
the nipple. Repeat this procedure at the opposite end
of the hose being installed.
(3) Using spring tension clamp pliers, compress
and slide the clamps that secure each end of the
heater hose over the tube or nipple. Release the
clamp when it is over the tube or nipple.
(4) Refill the engine cooling system. (Refer to 7 -
COOLING - STANDARD PROCEDURE - COOLING
SYSTEM REFILL).
LIQUID LINE
REMOVAL
The front air conditioner liquid line is serviced in
two sections. The front section connects between the
condenser and the filter/drier and includes the high
side service port on the fitting for the filter/drier. The
rear section connects between the filter/drier and the
expansion valve and includes the fitting for the A/C
pressure transducer. On models equipped with the
optional rear air conditioner, the rear section of the
front air conditioner liquid line also includes a liquid
line hose and tube extension that connects the front
liquid line to the liquid line for the rear air condi-
tioner.
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).
FRONT SECTION
(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) Remove 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 (Fig. 26).
(5) Remove the five small screws that secure the
front fascia grille inserts to the radiator sight shield.
(6) Remove the radiator sight shield from the radi-
ator closure panel crossmember.
Fig. 25 Heater Return - 3.3/3.8L Engine w/Oil Cooler
1 - ENGINE INLET NIPPLE
2 - HEATER RETURN TUBE & HOSE
3 - SCREW
4 - SCREW
5 - OIL COOLER
7 - HEATER RETURN HOSE
24 - 82 PLUMBING - FRONTRS
HEATER HOSE (Continued)
ProCarManuals.com

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) Remove the A/C pressure transducer from the
fitting on the front liquid line rear section. (Refer to
24 - HEATING & AIR CONDITIONING/CONTROLS
- FRONT/A/C PRESSURE TRANSDUCER - REMOV-
AL).
(6) Remove the nut that secures the A/C ground
strap to the weld stud on the top of the right front
strut tower (Fig. 28).
(7) Remove the A/C ground strap eyelet terminal
connector from the weld stud.
(8) Remove the screw that secures the liquid line
rear section fitting to the top of the filter-drier.
(9) Disconnect the liquid line fitting from the fil-
ter-drier outlet port.
(10) Remove the seal from the liquid line fitting
and discard.
(11) Install plugs in, or tape over the opened liquid
line fitting and the filter-drier outlet port.
(12) Remove the nut that secures the suction line
and liquid line fittings to the expansion valve.
(13) Disconnect the suction line and liquid line fit-
tings from the expansion valve.
(14) Remove the seals from the suction line and
liquid line fittings and discard.
(15) Install plugs in, or tape over the opened suc-
tion line and liquid line fittings and both expansion
valve ports.
(16) If the vehicle is equipped with the optional
rear air conditioner, go to Step 17. If the vehicle does
not have the optional rear air conditioner, go to Step
23.
(17) Raise and support the vehicle.
(18) 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. 29).
(19) Disconnect the front liquid line extension fit-
ting from the underbody liquid line fitting for the
rear air conditioner.
(20) Remove the seal from the underbody liquid
line fitting and discard.
(21) Install plugs in, or tape over the opened liquid
line fittings.
(22) Lower the vehicle.
(23) Remove the front liquid line rear section from
the engine compartment.
INSTALLATION
The front air conditioner liquid line is serviced in
two sections. The front section connects between the
condenser and the filter/drier and includes the high
side service port on the fitting for the filter/drier. The
rear section connects between the filter/drier and the
expansion valve and includes the fitting for the A/C
pressure transducer. On models equipped with the
optional rear air conditioner, the rear section of the
front air conditioner liquid line also includes a liquid
line hose and tube extension that connects the front
liquid line to the liquid line for the rear air condi-
tioner.
FRONT SECTION
(1) Position the front section of the front liquid
line into the engine compartment.
(2) Remove the tape or plugs from the liquid line
front section fitting for the filter-drier and the filter-
drier inlet port (Fig. 28).
(3) Lubricate a new rubber O-ring seal with clean
refrigerant oil and install it on the liquid line fitting.
(4) Reconnect the liquid line fitting to the filter-
drier inlet port on the top of the filter-drier.
(5) Install and tighten the screw that secures the
liquid line fitting to the filter-drier. Tighten the screw
to 2 N´m (16 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 (Fig. 27).
Fig. 29 Underbody Connections
1 - SUCTION LINE EXTENSION
2 - LIQUID LINE EXTENSION
3 - TIE STRAP
4- HEATER LINE EXTENSIONS
5 - UNDERBODY LINES
24 - 84 PLUMBING - FRONTRS
LIQUID LINE (Continued)
ProCarManuals.com

(6) 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.).
(7) Remove the tape or plugs from the liquid line
front section fitting for the filter-drier and the filter-
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 filter-
drier inlet port on the top of the filter-drier.
(10) 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.).
(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.
OPERATION
R-134a refrigerant is not compatible with R-12
refrigerant in an air conditioning system. Even a
small amount of R-12 added to an R-134a refrigerant
system will cause compressor failure, refrigerant oil
sludge or poor air conditioning system performance.
In addition, the PolyAlkylene Glycol (PAG) synthetic
refrigerant oils used in an R-134a refrigerant system
are not compatible with the mineral-based refriger-
ant oils used in an R-12 refrigerant system. R-134a
refrigerant system service ports, service tool couplers
and refrigerant dispensing bottles have all been
designed with unique fittings to ensure that an
R-134a system is not accidentally contaminated with
the wrong refrigerant (R-12). There are also labels
posted in the engine compartment of the vehicle and
on the compressor identifying to service techniciansthat the air conditioning system is equipped with
R-134a.
DIAGNOSIS AND TESTING - REFRIGERANT
SYSTEM CHARGE LEVEL
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 proper amount of R-134a refrigerant for
the refrigerant system in this model is:
²Single or Dual Zone (Front Unit Only)- 0.96
kilograms (2.13 pounds or 34 ounces)
²Three Zone (Front and Rear Units)- 1.31
kilograms (2.88 pounds or 46 ounces)
The procedure that follows should be used to deter-
mine whether the refrigerant system contains the
proper refrigerant charge. Symptoms of an improper
refrigerant charge (low) include: poor air conditioner
performance, fog emitted from the air conditioner
outlets, a hissing sound from the expansion valve/
evaporator area. There are two different methods
with which the refrigerant charge level may be
tested:
²Using a DRBIIItscan tool, a thermocouple and
the Charge Determination Chart (Fig. 31). Refer to
the appropriate diagnostic information.
²Using a manifold gauge set, a thermocouple and
the Charge Determination Chart (Fig. 31).
A temperature probe is required to measure liquid
line temperature. The clamp-on, Type K thermocou-
ple temperature probe used in this procedure is
available through the DaimlerChrysler Professional
Service Equipment (PSE) program. This probe (PSE
#66-324-0014 or #80PK-1A) is compatible with tem-
perature-measuring instruments that accept Type K
thermocouples, and have a miniature connector
input. Other temperature probes are available
through aftermarket sources; however, all references
in this procedure will reflect the use of the probe
made available through the PSE program.
In order to use the temperature probe, a digital
thermometer will also be required. If a digital ther-
mometer is not available, an adapter is available
through the PSE program that will convert any stan-
dard digital multimeter into a digital thermometer.
This adapter is designed to accept any standard Type
K thermocouple. If a digital multimeter is not avail-
able, this tool is also available through the PSE pro-
gram.
RSPLUMBING - FRONT24-87
RECEIVER/DRIER (Continued)
ProCarManuals.com

NOTE: When connecting the service equipment
couplings to the refrigerant system service ports,
be certain that the valve of each coupling is fully
closed. This will reduce the amount of effort
required to make the connection.
(1) Remove the caps from the refrigerant system
service ports and attach a manifold gauge set or a
R-134a refrigerant recovery/recycling/charging sta-
tion that meets SAE Standard J2210 to the refriger-
ant system.
(2) Attach a clamp-on thermocouple to the liquid
line. The thermocouple must be placed as close to the
A/C pressure transducer as possible to accurately
observe liquid line temperature.
(3) Bring the refrigerant system up to operating
temperature and pressure. This is done by allowing
the engine to run at idle under the following condi-
tions for five minutes.
(a) Front windows are open.
(b) Transaxle in Park.
(c) Front heater-A/C controls set to outside air,
full cool, panel mode, blower high, and compressor
engaged.
(d) If the vehicle is so equipped, the rear heater-
A/C controls must be set to full cool and blower
high.(4) Raise the liquid line (discharge) pressure to
about 1793 kPa (260 psi) by placing a piece of card-
board over part of the front side of the condenser. To
place the cardboard properly, remove the upper radi-
ator sight shield from the front fascia. Cover only
enough of the condenser to raise and maintain the
liquid line pressure at the specified level.
(5) Observe the liquid line (discharge) pressure
and liquid line temperature. Using the Charge Deter-
mination Chart (Fig. 31), determine whether the
refrigerant system is operating within the Proper
Charge Range.
(a) If the refrigerant system is operating in the
Undercharged area of the chart, add 0.057 kilo-
gram (0.125 pound or 2 ounces) of refrigerant to
the system.
(b) If the refrigerant system is operating in the
Overcharged area of the chart, reclaim 0.057 kilo-
gram (0.125 pound or 2 ounces) of refrigerant from
the system.
(6) Recheck the system charge level following each
refrigerant adjustment. Continue this process until
the system readings are in the Proper Charge Range
area on the Charge Determination Chart.
Fig. 31 Charge Determination Chart, Ambient Test Condition 85ÉF
24 - 88 PLUMBING - FRONTRS
REFRIGERANT (Continued)
ProCarManuals.com

DIAGNOSIS AND TESTING - REFRIGERANT
SYSTEM LEAKS
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).
If the air conditioning system is not cooling prop-
erly, determine if the refrigerant system is fully-
charged. (Refer to 24 - HEATING & AIR
CONDITIONING/PLUMBING - FRONT/REFRIGER-
ANT - DIAGNOSIS AND TESTING - REFRIGER-
ANT SYSTEM CHARGE LEVEL).
If the refrigerant system is low or empty; a leak at
a refrigerant line, connector fitting, component, or
component seal is likely. While an oily residue on or
near refrigerant system lines, connector fittings, com-
ponents, or component seals can indicate the general
location of a possible refrigerant leak, the exact leak
location should be confirmed with an electronic leak
detector prior to component repair or replacement.
An electronic leak detector designed for R-134a
refrigerant is recommended for locating and confirm-
ing refrigerant system leaks. See the operating
instructions supplied by the equipment manufacturer
for proper care and use of this equipment.
To detect a leak in the refrigerant system, perform
one of the following procedures as indicated by the
results of the refrigerant system charge level test.
SYSTEM EMPTY
(1) Evacuate the refrigerant system. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
FRONT/REFRIGERANT - STANDARD PROCE-
DURE - REFRIGERANT SYSTEM EVACUATE).
(2) Connect and dispense 0.283 kilograms (0.625
pounds or 10 ounces) of R-134a refrigerant into the
evacuated refrigerant system. (Refer to 24 - HEAT-
ING & AIR CONDITIONING/PLUMBING - FRONT/
REFRIGERANT - STANDARD PROCEDURE -
REFRIGERANT SYSTEM CHARGE).
(3) Proceed to the SYSTEM LOW procedures.
SYSTEM LOW
(1) Position the vehicle in a wind-free work area.
This will aid in detecting small leaks.
(2) Bring the refrigerant system up to operating
temperature and pressure. This is done by allowing
the engine to run at idle under the following condi-
tions for five minutes, then turning the engine off.
(a) Front windows are open.
(b) Rear air conditioner Off (if equipped).(c) Transaxle in Park.
(d) Front heater-A/C controls set to outside air,
panel mode, blower high, and compressor engaged.
(3) Wait five to seven minutes and, with the
engine not running, use a electronic R-134a leak
detector and search for leaks. Because R-134a refrig-
erant is heavier than air, the leak detector probe
should be moved slowly along the bottom side of all
refrigerant lines, connector fittings and components.
(4) To inspect an evaporator for leaks, insert the
electronic leak detector probe into a floor outlet or
the recirculation air intake.
STANDARD PROCEDURE - REFRIGERANT
SYSTEM SERVICE EQUIPMENT
RECOVERY/RECYCLING STATION
When servicing the air conditioning system, a
R-134a refrigerant recovery/recycling/charging sta-
tion that meets SAE Standard J2210 must be used
(Fig. 32). Contact PSE or an automotive service
equipment supplier for refrigerant recovery/recycling/
charging equipment. See the operating instructions
supplied by the equipment manufacturer for proper
care and use of this equipment.
MANIFOLD GAUGE SET CONNECTIONS
CAUTION: Do not use an R-12 manifold gauge set
on an R-134a system. The refrigerants are not com-
patible and system damage will result.
A manifold gauge set may be needed with some
recovery/recycling/charging equipment (Fig. 33). The
service hoses on the gauge set being used should
have manual (turn wheel), or automatic back-flow
Fig. 32 Refrigerant Recovery/Recycling Station -
Typical
1 - R-134 REFRIGERANT RECOVERY MACHINE
RSPLUMBING - FRONT24-89
REFRIGERANT (Continued)
ProCarManuals.com

ND-8 PAG refrigerant oil. Use only refrigerant oil of
this same type to service the refrigerant system.
OPERATION
After performing any refrigerant recovery or recy-
cling operation, always replenish the refrigerant sys-
tem with the same amount of the recommended
refrigerant oil as was removed. Too little refrigerant
oil can cause compressor damage, and too much can
reduce air conditioning system performance. PAG
refrigerant oil is much more hygroscopic than min-
eral oil, and will absorb any moisture it comes into
contact with, even moisture in the air. The PAG oil
container should always be kept tightly capped until
it is ready to be used. After use, recap the oil con-
tainer immediately to prevent moisture contamina-
tion.
STANDARD PROCEDURE - REFRIGERANT OIL
LEVEL
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).
When an air conditioning system is assembled at
the factory, all components except the compressor are
refrigerant oil free. After the refrigerant system has
been charged and operated, the refrigerant oil in the
compressor is dispersed throughout the refrigerant
system. The receiver/drier, evaporator, condenser, and
compressor will each retain a significant amount of
the needed refrigerant oil.
It is important to have the correct amount of oil in
the refrigerant system. This ensures proper lubrica-
tion of the compressor. Too little oil will result in
damage to the compressor. Too much oil will reduce
the cooling capacity of the air conditioning system.
It will not be necessary to check the oil level in the
compressor or to add oil, unless there has been an oil
loss. An oil loss may occur due to a rupture or leak
from a refrigerant line, a connector fitting, a compo-
nent, or a component seal. If a leak occurs, add 30
milliliters (1 fluid ounce) of refrigerant oil to the
refrigerant system after the repair has been made.
Refrigerant oil loss will be evident at the leak point
by the presence of a wet, shiny surface around the
leak.
Refrigerant oil must be added when an receiver/
drier, evaporator or condenser is replaced. See the
Refrigerant Oil Capacities chart for the proper
amount of refrigerant oil to add. When a compressoris replaced, the refrigerant oil must be drained from
the old compressor and measured. Drain all of the
refrigerant oil from the new compressor, then fill the
new compressor with the same amount of fresh new
refrigerant oil that was drained out of the old com-
pressor.
REFRIGERANT OIL CAPACITIES
Front A/C Front & Rear
A/C
COMPONENT ml fl oz ml fl oz
Compressor 150 5.0 220 7.4
Filter-Drier 30 1.0 30 1.0
Condenser 30 1.0 30 1.0
Front Evaporator 60 2.0 60 2.0
Rear Evap. (including
underbody lines)N/A N/A 60 2.0
Compressor Drain and measure the oil
from the old compressor -
See text above.
SUCTION LINE
REMOVAL
The front air conditioner suction line includes the
low side service port on a section of tubing located
near the compressor. On models equipped with the
optional rear air conditioner, the front air conditioner
suction line also includes a suction line hose and
tube extension that connects the front suction line to
the suction line for the rear air conditioner.
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 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.
24 - 92 PLUMBING - FRONTRS
REFRIGERANT OIL (Continued)
ProCarManuals.com

(12) Install plugs in, or tape over the opened evap-
orator line extension fittings and both expansion
valve ports.
INSTALLATION - REAR EVAPORATOR
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 rear heater-A/C hous-
ing.
(2) Position the upper half of the rear heater-A/C
housing onto the lower half (Fig. 1).
(3) Install the three small metal spring clips that
secure the upper half of the rear heater-A/C housing
to the lower half.
(4) Install and tighten the three screws that secure
the upper half of the rear heater-A/C housing to the
lower half. Tighten the screws to 2 N´m (18 in. lbs.).
(5) Install the rubber grommet that seals the evap-
orator inlet and outlet tubes to the rear heater-A/C
housing near the expansion valve.
(6) Reinstall the rear expansion valve onto the
rear 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 heater-A/C unit housing into
the vehicle. (Refer to 24 - HEATING & AIR CONDI-
TIONING/DISTRIBUTION - REAR/REAR HEATER-
A/C HOUSING - INSTALLATION).
INSTALLATION - 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 heater-A/C housing
base (Fig. 3).
(4) Position the evaporator line extension seal
plate over the expansion valve stud.
(5) Install and tighten 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 and tighten the two screws that secure
the expansion valve bracket to the lower rear heater-
A/C unit housing. Tighten the screws to 2 N´m (18 in.
lbs.).
(8) Install and tighten 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 heater-A/C
unit housing base (Fig. 2).
(11) Install and tighten the screw that secures the
capture plate to the base of the rear heater-A/C unit
housing. Tighten the screw to 2 N´m (18 in. lbs.).
(12) Reinstall the rear heater-A/C unit housing
into the vehicle. (Refer to 24 - HEATING & AIR
CONDITIONING/DISTRIBUTION - REAR/REAR
HEATER-A/C HOUSING - INSTALLATION).
EXPANSION VALVE
DESCRIPTION
The rear ªHº valve-type thermal expansion valve
(TXV) is located at the rear of the rear heater-A/C
unit housing between the evaporator line extension
and the evaporator coil. High-pressure, low tempera-
ture liquid 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. Models
equipped with the optional Automatic Temperature
Control (ATC) system also have an electric solenoid
that is located on the inboard side of and integral to
the rear expansion valve. 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 expansion valve
solenoid on models equipped with the optional ATC
system electrically blocks refrigerant from passing
through the expansion valve orifice and circulating
24 - 98 PLUMBING - REARRS
EVAPORATOR (Continued)
ProCarManuals.com

through the rear evaporator when the rear air condi-
tioner is turned Off.
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
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 suitable super-cold material.Do not spray
R-134a or R-12 refrigerant on the expansionvalve 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) If the vehicle is equipped with the optional
Automatic Temperature Control (ATC) system, dis-
connect the expansion valve solenoid pigtail wire con-
nector from the rear HVAC wire harness connector
(Fig. 4).
(5) Remove the two screws that secure the expan-
sion valve to the evaporator tube sealing plate.
(6) Remove the expansion valve from the evapora-
tor tubes.
(7) Remove the seals from the evaporator tube fit-
tings and discard.
(8) 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 evaporator
tube fittings and both expansion valve ports.
RSPLUMBING - REAR24-99
EXPANSION VALVE (Continued)
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