2002 JEEP GRAND CHEROKEE pressure testing

However, evaporator capacity used to reduce the
amount of moisture in the air is not wasted. Wring-
ing some of the moisture out of the air entering the
vehicle adds to the comfort of the passengers.
Although, an owner may expect too much from their
air conditioning system on humid days. A perfor-
mance test is the best way to determine whether the
system is performing up to standard. This test also
provides valuable clues as to the possible cause of
trouble with the air conditioning system.
If the vehicle has the optional Automatic Zone Control
(AZC) system, and has intermittent operational prob-
lems or fault codes, be certain that the wire harness
connectors on the HVAC housing are properly seated
(Fig. 2). To check this condition, unplug the two wire
harness connector halves, then plug them in again.
Before performing the following procedure, (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMB-
ING - CAUTION) (Refer to 24 - HEATING & AIR
CONDITIONING/PLUMBING - WARNING). The air
temperature in the test room and in the vehicle must
be a minimum of 21É C (70É F) for this test.
(1)
Connect a tachometer and a manifold gauge set.
(2) If the vehicle has the standard manual temper-
ature control, set the A/C Heater mode control switch
knob in the Panel position, the temperature control
knob in the full cool (Fresh Air Mode) position, the
A/C button in the On position, and the blower motor
switch knob in the highest speed position. If the vehi-
cle has the optional AZC, set the A/C Heater mode
control switch knob in the Panel position, the tem-
perature control knob in the full cool position, the
A/C button in the On position, and the blower motor
switch knob in the highest (manual) speed position.
(3) Start the engine and hold the idle at 1,300 rpm
with the compressor clutch engaged.
(4) The engine should be at operating temperature.
The doors and windows must be open.
(5)
Insert a thermometer in the driver side center
A/C (panel) outlet. Operate the engine for five minutes.
(6) The compressor clutch may cycle, depending
upon the ambient temperature and humidity.(7) With the compressor clutch engaged, record the
discharge air temperature and the compressor dis-
charge pressure.
(8) Compare the discharge air temperature to the
Performance Temperature and Pressure chart. If the
discharge air temperature is high, (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
DIAGNOSIS AND TESTING - REFRIGERANT SYS-
TEM LEAKS) and (Refer to 24 - HEATING & AIR
CONDITIONING/PLUMBING - STANDARD PRO-
CEDURE - REFRIGERANT SYSTEM CHARGE).
Performance Temperature and Pressure
Ambient Air Temperature
and Humidity21É C
(70É F @ 80%
humidity)27É C
(80É F @ 80%
humidity)32É C
(90É F @ 80%
humidity)38É C
(100ÉF@50%
humidity)43É C
110É F @ 20%
humidity)
Air Temperature at Center
Panel Outlet10 to 13É C
(50 to 55É F)14 to 17É C
(58 to 63É F)15 to 18É C
(60 to 65É F)17 to 20É C
(63 to 68É F)14 to 17É C
(58 to 63É F)
Evaporator Inlet Pressure
at Charge Port241 to 276 kPa
(35 to 40 psi)262 to 290 kPa
(38 to 42 psi)269 to 296 kPa
(39 to 43 psi)275 to 303 kPa
(40 to 44 psi)262 to 290 kPa
(38 to 42 psi)
Compressor Discharge
Pressure1241 to 1792
kPa
(180 to 260 psi)1380 to 1930
kPa
(200 to 280 psi)1380 to 1930
kPa
(200 to 280 psi)1655 to 2206
kPa
(240 to 320 psi)1567 to 2068
kPa
(220 to 300 psi)
Note: The discharge air temperatures will be lower if the humidity is less than the percentages shown.
Fig. 2 HVAC Housing - (rear view)
1 - Instrument Panel
2 - Air Intake
3 - Expansion Valve
4 - HVAC Housing
5 - Heater Core Input/Output Ports
6 - Instrument Panel Wiring Harness
7 - Blower Motor
WJHEATING & AIR CONDITIONING 24 - 3
HEATING & AIR CONDITIONING (Continued)

(9) Compare the compressor discharge pressure to
the Performance Temperature and Pressure chart. If
the compressor discharge pressure is high, see the
Pressure Diagnosis chart.
Pressure Diagnosis
Condition Possible Causes Correction
Rapid compressor clutch
cycling (ten or more cycles
per minute).1. Low refrigerant system
charge.1. See Plumbing/Diagnosis and Testing -
Refrigerant System Leaks in this group. Test the
refrigerant system for leaks. Repair, evacuate and
charge the refrigerant system, if required.
Equal pressures, but the
compressor clutch does not
engage.1. No refrigerant in the
refrigerant system.1. See Plumbing/Diagnosis and Testing -
Refrigerant System Leaks in this group. Test the
refrigerant system for leaks. Repair, evacuate and
charge the refrigerant system, if required.
2. Faulty fuse. 2. Check the fuses in the Power Distribution
Center and the junction block. Repair the shorted
circuit or component and replace the fuses, if
required.
3. Faulty a/c compressor
clutch coil.3. See A/C Compressor/Diagnosis and Testing -
Compressor Clutch Coil in this group. Test the
compressor clutch coil and replace, if required.
4. Faulty compressor clutch
relay.4. See A/C Compressor Clutch Relay/Diagnosis
and Testing - Compressor Clutch Relay in this
group. Test the compressor clutch relay and relay
circuits. Repair the circuits or replace the relay, if
required.
6. Faulty a/c high pressure
transducer.6. See A/C High Pressure Transducer/Diagnosis
and Testing in this group. Test the a/c high
pressure transducer and replace, if required.
7. Faulty Fin Probe. 7. Check for open circuit.
8. Faulty Powertrain Control
Module (PCM).8. Refer to the proper Diagnostic Procedures
manual for testing of the PCM. Test the PCM and
replace, if required.
Normal pressures, but A/C
Performance Test air
temperatures at center panel
outlet are too high.1. Excessive refrigerant oil in
system.1. See Refrigerant Oil/Standard Procedure -
Refrigerant Oil Level in this group. Recover the
refrigerant from the refrigerant system and
inspect the refrigerant oil content. Restore the
refrigerant oil to the proper level, if required.
2. Blend door inoperative or
sealing improperly.2. See Blend Door in this group. Inspect the
blend door for proper operation and sealing and
correct, if required.
3. Blend door actuator faulty
or inoperative.3. Perform blend door actuator diagnosis, replace
if faulty.
24 - 4 HEATING & AIR CONDITIONINGWJ
HEATING & AIR CONDITIONING (Continued)

Pressure Diagnosis
Condition Possible Causes Correction
The low side pressure is
normal or slightly low, and
the high side pressure is too
low.1. Low refrigerant system
charge.1. See Plumbing/Diagnosis and Testing -
Refrigerant System Leaks in this group. Test the
refrigerant system for leaks. Repair, evacuate and
charge the refrigerant system, if required.
2. Refrigerant flow through
the accumulator is restricted.2. See Accumulator in this group. Replace the
restricted accumulator, if required.
3. Refrigerant flow through
the evaporator coil is
restricted.3. See A/C Evaporator in this group. Replace the
restricted evaporator coil, if required.
4. Faulty compressor. 4. See A/C Compressor in this group. Replace
the compressor, if required.
The low side pressure is
normal or slightly high, and
the high side pressure is too
high.1. Condenser air flow
restricted.1. Check the condenser for damaged fins, foreign
objects obstructing air flow through the condenser
fins, and missing or improperly installed air seals.
Refer to Cooling for more information on air
seals. Clean, repair, or replace components as
required.
2. Inoperative cooling fan. 2. Refer to Cooling for more information. Test the
cooling fan and replace, if required.
3. Refrigerant system
overcharged.3. See Plumbing/Standard Procedure -
Refrigerant System Charge in this group. Recover
the refrigerant from the refrigerant system.
Charge the refrigerant system to the proper level,
if required.
4. Air in the refrigerant
system.4. See Plumbing/Diagnosis and Testing -
Refrigerant System Leaks in this group. Test the
refrigerant system for leaks. Repair, evacuate and
charge the refrigerant system, if required.
5. Engine overheating. 5. Refer to Cooling for more information. Test the
cooling system and repair, if required.
The low side pressure is too
high, and the high side
pressure is too low.1. Accessory drive belt
slipping.1. Refer to Cooling for more information. Inspect
the accessory drive belt condition and tension.
Tighten or replace the accessory drive belt, if
required.
2. Faulty compressor. 2. See A/C Compressor in this group. Replace
the compressor, if required.
The low side pressure is too
low, and the high side
pressure is too high.1. Restricted refrigerant flow
through the refrigerant lines.1. See Liquid, Suction, and Discharge Line in this
group. Inspect the refrigerant lines for kinks, tight
bends or improper routing. Correct the routing or
replace the refrigerant line, if required.
2. Restricted refrigerant flow
through the a/c expansion
valve.2. See A/C Expansion Valve in this group.
Replace the Expansion Valve if restricted.
3. Restricted refrigerant flow
through the condenser.3. See A/C Condenser in this group. Replace the
restricted condenser, if required.
WJHEATING & AIR CONDITIONING 24 - 5
HEATING & AIR CONDITIONING (Continued)

CONTROLS
TABLE OF CONTENTS
page page
CONTROLS
DIAGNOSIS AND TESTING - VACUUM
SYSTEM............................10
A/C COMPRESSOR CLUTCH
DESCRIPTION.........................13
OPERATION...........................13
DIAGNOSIS AND TESTING - COMPRESSOR
CLUTCH COIL........................13
STANDARD PROCEDURE - COMPRESSOR
CLUTCH BREAK-IN....................14
REMOVAL.............................14
INSPECTION..........................15
INSTALLATION.........................15
A/C COMPRESSOR CLUTCH RELAY
DESCRIPTION.........................16
OPERATION...........................16
DIAGNOSIS AND TESTING - A/C
COMPRESSOR CLUTCH RELAY..........16
REMOVAL.............................17
INSTALLATION.........................17
A/C HEATER CONTROL
DESCRIPTION.........................17
OPERATION...........................17
DIAGNOSIS AND TESTING - AUTOMATIC
ZONE CONTROL SYSTEM..............18
REMOVAL.............................24
INSTALLATION.........................25
A/C PRESSURE TRANSDUCER
DESCRIPTION.........................25
OPERATION...........................25
DIAGNOSIS AND TESTING - A/C PRESSURE
TRANSDUCER.......................26
REMOVAL.............................26
INSTALLATION.........................26
BLOWER MOTOR CONTROLLER
DESCRIPTION.........................26
OPERATION...........................26
REMOVAL.............................27
INSTALLATION.........................27
BLOWER MOTOR RESISTOR BLOCK
DESCRIPTION.........................27
OPERATION...........................27
DIAGNOSIS AND TESTING - BLOWER
MOTOR RESISTOR BLOCK..............27
REMOVAL.............................28
INSTALLATION.........................28BLOWER MOTOR SWITCH
DESCRIPTION.........................28
OPERATION...........................28
DIAGNOSIS AND TESTING - BLOWER
MOTOR SWITCH-MANUAL TEMPERATURE
CONTROL SYSTEM....................28
REMOVAL.............................29
IN-CAR TEMPERATURE SENSOR
DESCRIPTION.........................29
OPERATION...........................29
REMOVAL.............................29
BLEND DOOR ACTUATOR
DESCRIPTION.........................30
REMOVAL.............................30
INSTALLATION.........................30
MODE DOOR ACTUATOR
DESCRIPTION.........................30
REMOVAL
REMOVAL - HEAT/DEFROST - PANEL/
DEFROST DOOR ELECTRIC ACTUATOR . . . 31
REMOVAL - HEAT/DEFROST DOOR
VACUUM ACTUATOR..................31
REMOVAL - PANEL/DEFROST DOOR
VACUUM ACTUATOR..................32
INSTALLATION
INSTALLATION - HEAT/DEFROST -
PANEL/DEFROST DOOR ELECTRIC
ACTUATOR..........................32
INSTALLATION - HEAT/DEFROST DOOR
VACUUM ACTUATOR..................33
INSTALLATION - PANEL/DEFROST DOOR
VACUUM ACTUATOR..................33
RECIRCULATION DOOR ACTUATOR
DESCRIPTION.........................33
REMOVAL
REMOVAL - RECIRCULATION DOOR
VACUUM ACTUATOR..................33
REMOVAL - RECIRCULATION DOOR
ELECTRIC ACTUATOR.................33
INSTALLATION
INSTALLATION - RECIRCULATION DOOR
VACUUM ACTUATOR..................34
INSTALLATION - RECIRCULATION DOOR
ELECTRIC ACTUATOR.................34
VACUUM CHECK VALVE
DESCRIPTION.........................34
OPERATION...........................34
REMOVAL.............................34
INSTALLATION.........................34
WJCONTROLS 24 - 9

A/C COMPRESSOR CLUTCH
DESCRIPTION
The compressor clutch assembly consists of a sta-
tionary electromagnetic coil, a hub bearing and pul-
ley assembly, and a clutch plate (Fig. 4). The
electromagnetic coil unit and the hub bearing and
pulley assembly are each retained on the nose of the
compressor front housing with snap rings. The clutch
plate is keyed to the compressor shaft and secured
with a bolt.
OPERATION
The compressor clutch components provide the
means to engage and disengage the compressor from
the engine serpentine accessory drive belt. When the
clutch coil is energized, it magnetically draws the
clutch into contact with the pulley and drives the
compressor shaft. When the coil is not energized, the
pulley freewheels on the clutch hub bearing, which is
part of the pulley. The compressor clutch and coil are
the only serviced parts on the compressor.
The compressor clutch engagement is controlled by
several components: the a/c switch on the a/c heater
control panel, the Automatic Zone Control (AZC) con-
trol module (if the vehicle is so equipped), the evap-
orator probe, the a/c high pressure transducer, the
a/c compressor clutch relay, the body control module
(BCM) and the Powertrain Control Module (PCM).
The PCM may delay compressor clutch engagement
for up to thirty seconds. Refer to Electronic Control
Modules for more information on the PCM controls.
DIAGNOSIS AND TESTING - COMPRESSOR
CLUTCH COIL
For circuit descriptions and diagrams, refer to the
appropriate wiring diagrams. The battery must be
fully-charged before performing the following tests.
Refer to Battery for more information.
(1) Connect an ammeter (0 to 10 ampere scale) in
series with the clutch coil terminal. Use a voltmeter
(0 to 20 volt scale) with clip-type leads for measuring
the voltage across the battery and the compressor
clutch coil.
(2) With the a/c heater mode control switch in any
a/c mode, the a/c heater control a/c switch in the ON
position, and the blower motor switch in the lowest
speed position, start the engine and run it at normal
idle.
(3) The compressor clutch coil voltage should read
within 0.2 volts of the battery voltage. If there is
voltage at the clutch coil, but the reading is not
within 0.2 volts of the battery voltage, test the clutch
coil feed circuit for excessive voltage drop and repair
as required. If there is no voltage reading at the
clutch coil, use a DRBIIItscan tool and the appro-
priate diagnostic information for testing of the com-
pressor clutch circuit. The following components
must be checked and repaired as required before you
can complete testing of the clutch coil:
²Fuses in the junction block and the Power Dis-
tribution Center (PDC)
²A/C heater mode control switch
²A/C compressor clutch relay
²A/C high pressure transducer
²A/C evaporator probe
²Powertrain Control Module (PCM)
²Body Control Module (BCM)
(4) The compressor clutch coil is acceptable if the
current draw measured at the clutch coil is 2.0 to 3.9
amperes with the electrical system voltage at 11.5 to
12.5 volts. This should only be checked with the work
area temperature at 21É C (70É F). If system voltage
is more than 12.5 volts, add electrical loads by turn-
ing on electrical accessories until the system voltage
drops below 12.5 volts.
(a) If the clutch coil current reading is four
amperes or more, the coil is shorted and should be
replaced.
(b) If the clutch coil current reading is zero, the
coil is open and should be replaced.
Fig. 4 COMPRESSOR CLUTCH - TYPICAL
1 - CLUTCH PLATE
2 - SHAFT KEY
3 - PULLEY
4 - COIL
5 - CLUTCH SHIMS
6 - SNAP RING
7 - SNAP RING
WJCONTROLS 24 - 13

DIAGNOSIS AND TESTING - A/C PRESSURE
TRANSDUCER
The A/C pressure transducer is tested using a
DRBIIItscan tool. Refer to the appropriate diagnos-
tic information. Before testing the A/C pressure
transducer, be certain that the transducer wire har-
ness connection is clean of corrosion and properly
connected. For the air conditioning system to operate,
an A/C pressure transducer voltage reading between0.7 and 4.56 volts is required. Voltage outside this
range indicate a low or high refrigerant system pres-
sure condition to the Powertrain Control Module
(PCM). The PCM is programmed to respond to a low
or high refrigerant system pressure by suppressing
operation of the compressor. Refer to the A/C Pres-
sure Transducer Voltage table for the possible condi-
tion indicated by the transducer voltage readings.
A/C PRESSURE TRANSDUCER VOLTAGE
VOLTAGE POSSIBLE INDICATION
0.0 1. NO SENSOR SUPPLY VOLTAGE FROM PCM.
2. SHORTED SENSOR CIRCUIT.
3. FAULTY TRANSDUCER
0.150 TO 0.450 1. AMBIENT TEMPERATURE BELOW 10É c (50É F).
2. LOW REFRIGERANT SYSTEM PRESSURE.
0.451 TO 4.519 1. NORMAL REFRIGERANT SYSTEM PRESSURE.
4.520 TO 4.850 1. HIGH REFRIGERANT SYSTEM PRESSURE.
5.0 1. OPEN SENSOR CIRCUIT.
2. FAULTY TRANSDUCER.
REMOVAL
WARNING: Transducer can be removed without
recoverying the system, but some loss of refriger-
ant can be expected(Refer to 24 - HEATING & AIR
CONDITIONING/PLUMBING - WARNING) and (Refer
to 24 - HEATING & AIR CONDITIONING/PLUMBING -
CAUTION).
(1) Disconnect and isolate the battery negative
cable.
(2) Disconnect the headlamp and dash wire har-
ness connector for the A/C pressure transducer from
the transducer connector receptacle.
(3) Using an open end wrench, unscrew the A/C
pressure transducer from the fitting on the discharge
line.
(4) Remove the seal from the A/C pressure trans-
ducer fitting and discard.
INSTALLATION
(1) Lubricate a new O-ring seal with clean refrig-
erant oil and install it on the A/C pressure trans-
ducer fitting.
(2) Using an open end wrench, install and tighten
the A/C pressure transducer onto the fitting on the
discharge line.
(3) Reconnect the headlamp and dash wire harness
connector for the A/C pressure transducer to the
transducer connector receptacle.(4) Reconnect the battery negative cable.
BLOWER MOTOR
CONTROLLER
DESCRIPTION
Models equipped with the optional Automatic Zone
Control (AZC) system have a blower motor controller.
The controller allows the selection of almost infi-
nitely variable blower motor speeds. The controller is
mounted to the HVAC housing, under the instrument
panel and just inboard of the blower motor, in the
same location used for the blower motor resistor on
manual temperature control systems. It can be
accessed without removing any other components.
OPERATION
The blower motor controller output to the blower
motor can be adjusted by the blower motor speed
switch knob on the AZC A/C Heater control panel, or
it can be adjusted automatically by the logic circuitry
and programming of the AZC control module. In
either case, the AZC control module sends the correct
pulse width modulated signal to the blower motor
controller to obtain the selected or programmed
blower motor speed.
The blower motor controller cannot be repaired
and, if faulty or damaged, it must be replaced.
24 - 26 CONTROLSWJ
A/C PRESSURE TRANSDUCER (Continued)

PLUMBING
TABLE OF CONTENTS
page page
PLUMBING
DESCRIPTION - REFRIGERANT LINE.......52
OPERATION - REFRIGERANT LINE.........52
WARNING.............................52
CAUTION
CAUTION...........................53
REFRIGERANT HOSES/LINES/TUBES
PRECAUTIONS.......................53
DIAGNOSIS AND TESTING - REFRIGERANT
SYSTEM LEAKS......................54
STANDARD PROCEDURE
STANDARD PROCEDURE - REFRIGERANT
SYSTEM SERVICE EQUIPMENT..........54
STANDARD PROCEDURE - REFRIGERANT
RECOVERY..........................55
STANDARD PROCEDURE - REFRIGERANT
SYSTEM EVACUATE...................55
STANDARD PROCEDURE - REFRIGERANT
SYSTEM CHARGE.....................56
SPECIFICATIONS
CHARGE CAPACITY...................57
A/C COMPRESSOR
DESCRIPTION
DESCRIPTION - A/C COMPRESSOR.......57
DESCRIPTION - HIGH PRESSURE RELIEF
VALVE..............................57
OPERATION
OPERATION - A/C COMPRESSOR........57
OPERATION - HIGH PRESSURE RELIEF
VALVE..............................57
DIAGNOSIS AND TESTING - COMPRESSOR
NOISE..............................58
REMOVAL
REMOVAL...........................58
REMOVAL - 2.7L TURBO DIESEL.........60
INSTALLATION
INSTALLATION.......................61
INSTALLATION - 2.7L TURBO DIESEL......61
A/C CONDENSER
DESCRIPTION.........................62
OPERATION...........................62
REMOVAL.............................62
INSTALLATION.........................63
A/C DISCHARGE LINE
REMOVAL
REMOVAL - 2.7L TURBO DIESEL.........63
REMOVAL...........................64INSTALLATION
INSTALLATION - 2.7L TURBO DIESEL......64
INSTALLATION.......................65
A/C EXPANSION VALVE
DESCRIPTION.........................65
OPERATION...........................65
DIAGNOSIS AND TESTING - A/C EXPANSION
VALVE ..............................65
REMOVAL.............................66
INSTALLATION.........................66
LIQUID LINE
REMOVAL
REMOVAL...........................66
REMOVAL - 2.7L TURBO DIESEL.........66
INSTALLATION
INSTALLATION.......................66
INSTALLATION - 2.7L TURBO DIESEL......67
SUCTION LINE
REMOVAL
REMOVAL...........................67
REMOVAL - 2.7L TURBO DIESEL.........68
INSTALLATION
INSTALLATION.......................68
INSTALLATION - 2.7L TURBO DIESEL......69
A/C EVAPORATOR
DESCRIPTION.........................69
OPERATION...........................69
REMOVAL.............................69
INSTALLATION.........................70
HEATER CORE
DESCRIPTION.........................71
OPERATION...........................71
REMOVAL.............................71
INSTALLATION.........................71
RECEIVER / DRIER
DESCRIPTION.........................72
OPERATION...........................72
REMOVAL.............................73
INSTALLATION.........................73
REFRIGERANT
DESCRIPTION.........................75
OPERATION...........................75
REFRIGERANT OIL
DESCRIPTION.........................75
OPERATION...........................75
STANDARD PROCEDURE - REFRIGERANT
OIL LEVEL...........................75
WJPLUMBING 24 - 51

ready. The refrigerant system should not be left open
to the atmosphere any longer than necessary. Cap or
plug all lines and fittings as soon as they are opened
to prevent the entrance of dirt and moisture. All lines
and components in parts stock should be capped or
sealed until they are to be installed.
All tools, including the refrigerant recycling equip-
ment, the manifold gauge set, and test hoses should
be kept clean and dry. All tools and equipment must
be designed for R-134a refrigerant.
DIAGNOSIS AND TESTING - REFRIGERANT
SYSTEM LEAKS
WARNING: REVIEW THE WARNINGS AND CAU-
TIONS IN THE FRONT OF THIS SECTION BEFORE
PERFORMING THE FOLLOWING OPERATION.
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - WARNING) (Refer to 24 - HEATING &
AIR CONDITIONING/PLUMBING - CAUTION)
If the air conditioning system is not cooling prop-
erly, determine if the refrigerant system is fully-
charged. (Refer to 24 - HEATING & AIR
CONDITIONING - DIAGNOSIS AND TESTING -
A/C PERFORMANCE)
An electronic leak detector designed for R-134a
refrigerant is recommended for locating and confirm-
ing refrigerant system leaks. Refer to the operating
instructions supplied by the equipment manufacturer
for proper care and use of this equipment.
An oily residue on or near refrigerant system lines,
connector fittings, components, or component seals
can indicate the general location of a possible refrig-
erant leak. However, the exact leak location should
be confirmed with an electronic leak detector prior to
component repair or replacement.
To detect a leak in the refrigerant system, perform
one of the following procedures:
SYSTEM EMPTY
(1) Evacuate the refrigerant system. (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE - REFRIGERANT SYS-
TEM 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 - STAN-
DARD PROCEDURE - REFRIGERANT SYSTEM
CHARGE)
(3) Position the vehicle in a wind-free work area.
This will aid in detecting small leaks.
(4) With the engine not running, use a electronic
R-134a leak detector and search for leaks. Because
R-134a refrigerant is heavier than air, the leak detec-tor probe should be moved slowly along the bottom
side of all refrigerant lines, connector fittings and
components.
(5) To inspect the evaporator coil for leaks, insert
the electronic leak detector probe into the center
instrument panel outlet. Set the blower motor switch
to the lowest speed position, the A/C button in the
On position, and select the Recirculation Mode.
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 with the air conditioning system
turned on for five minutes.
(3) With the engine not running, use a electronic
R-134a leak detector and search for leaks. Because
R-134a refrigerant is heavier than air, the leak detec-
tor probe should be moved slowly along the bottom
side of all refrigerant lines, connector fittings and
components.
(4) To inspect the evaporator coil for leaks, insert
the electronic leak detector probe into the center
instrument panel outlet. Set the blower motor switch
to the lowest speed position, the A/C button in the
On position, and select the Recirculation Mode.
STANDARD PROCEDURE
STANDARD PROCEDURE - REFRIGERANT
SYSTEM SERVICE EQUIPMENT
WARNING: EYE PROTECTION MUST BE WORN
WHEN SERVICING AN AIR CONDITIONING REFRIG-
ERANT SYSTEM. TURN OFF (ROTATE CLOCKWISE)
ALL VALVES ON THE EQUIPMENT BEING USED,
BEFORE CONNECTING TO OR DISCONNECTING
FROM THE REFRIGERANT SYSTEM. FAILURE TO
OBSERVE THESE WARNINGS MAY RESULT IN PER-
SONAL INJURY.
WARNING: REVIEW THE WARNINGS AND CAU-
TIONS IN THE FRONT OF THIS SECTION BEFORE
PERFORMING THE FOLLOWING OPERATION.
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - WARNING) (Refer to 24 - HEATING &
AIR CONDITIONING/PLUMBING - CAUTION)
When servicing the air conditioning system, a
R-134a refrigerant recovery/recycling/charging sta-
tion that meets SAE Standard J2210 must be used.
Contact an automotive service equipment supplier for
refrigerant recovery/recycling/charging equipment.
Refer to the operating instructions supplied by the
24 - 54 PLUMBINGWJ
PLUMBING (Continued)