2002 JEEP LIBERTY Oil diagram

INSTALLATION
(1) Position the horn relay in the proper receptacle
in the Junction Block (JB).
(2) Push down firmly on the relay until the termi-
nals are fully seated.
(3) Connect the battery negative cable.
REMOTE KEYLESS ENTRY
MODULE
DESCRIPTION
When an RKE lock message is sent to the Body
Control Module (BCM), the BCM actuates the doors
and the tailgate lock, the interior lighting is turned
off, the horn chirps (if this feature is enabled), the
exterior lamps flash (if this feature is enabled) and, if
the vehicle is so equipped, the Vehicle Theft Security
System (VTSS) is armed. When an RKE unlock mes-
sage is sent to the BCM, the BCM actuates the
driver side front door (or all doors and the tailgate if
this feature is enabled) unlock, the interior lighting
is turned on and, if the vehicle is so equipped, the
VTSS is disarmed.When an RKE panic message is sent to the BCM,
the BCM actuates the driver side front door (or all
doors and the tailgate if this feature is enabled)
unlock, the interior lighting is turned on and, if the
vehicle is so equipped, the VTSS is disarmed. The
panic message will also cause the exterior lamps
(including the headlights) to flash, and the horn to
pulse for about three minutes, or until a second panic
message is sent to the BCM. A vehicle speed of about
25.7 kilometers-per-hour (15 miles-per-hour) will also
cancel the panic event.
Refer to the owner's manual for more information
on the features, use and operation of the RKE sys-
tem.
OPERATION
Whenever the vehicle battery power is interrupted,
the Remote Keyless Module (RKE) Module will retain
all vehicle access codes in its memory. When replac-
ing or adding a key fob transmitter (maximum of 4) a
DRB IIItscan tool is required to program the RKE
Module to accept the new Vehicle Access Code if a
customer owned transmitter is not available.
If a functioning transmitter is available, (Refer to 8
- ELECTRICAL/POWER LOCKS/KEYLESS ENTRY
TRANSMITTER - STANDARD PROCEDURE)
DIAGNOSIS AND TESTING - REMOTE KEYLESS
ENTRY MODULE
Refer to the appropriate wiring information. The
wiring information includes wiring diagrams, proper
wire and connector repair procedures, further details
on wire harness routing and retention, as well as
pin-out and location views for the various wire har-
ness connectors, splices and grounds. Refer to the
proper Body Diagnostic Procedures Manual for test-
ing the Remote Keyless Entry system using a DRB
IIItscan tool.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the Junction Block (JB) (Refer to 8 -
ELECTRICAL/POWER DISTRIBUTION/JUNCTION
BLOCK - REMOVAL).
(3) Remove Remote Keyless Entry module from
Body Control Module (Fig. 5).
INSTALLATION
(1) Install Remote Keyless Entry module to Body
Control Module.
(2) Install Junction Block (JB) (Refer to 8 - ELEC-
TRICAL/POWER DISTRIBUTION/JUNCTION
BLOCK - INSTALLATION).
(3) Connect the battery negative cable.
Fig. 4 Power Lock Relay
30 - COMMON FEED
85 - COIL GROUND
86 - COIL BATTERY
87 - NORMALLY OPEN
87A - NORMALLY CLOSED
KJPOWER LOCKS 8N - 7
DOOR LOCK RELAY (Continued)

²Normally Closed Terminal- The normally
closed terminal (87A) is connected to the low speed
brush of the front wiper motor through a front wiper
high/low relay low speed output circuit, and is con-
nected to the low speed brush whenever the relay is
de-energized.
The wiper high/low relay can be diagnosed using
conventional diagnostic tools and methods.
DIAGNOSIS AND TESTING - WIPER HIGH/LOW
RELAY
The wiper high/low relay (Fig. 26) is located in the
Power Distribution Center (PDC) in the engine com-
partment near the battery. Refer to the appropriate
wiring information. The wiring information includes
wiring diagrams, proper wire and connector repair
procedures, details of wire harness routing and
retention, connector pin-out information and location
views for the various wire harness connectors, splices
and grounds.
(1) Remove the wiper high/low relay from the
PDC. (Refer to 8 - ELECTRICAL/WIPERS/WASH-
ERS/WIPER HIGH/LOW RELAY - REMOVAL).
(2) A relay in the de-energized position should
have continuity between terminals 87A and 30, and
no continuity between terminals 87 and 30. If OK, go
to Step 3. If not OK, replace the faulty relay.
(3) Resistance between terminals 85 and 86 (elec-
tromagnet) should be 75   8 ohms. If OK, go to Step
4. If not OK, replace the faulty relay.
(4) Connect a battery to terminals 85 and 86.
There should now be continuity between terminals30 and 87, and no continuity between terminals 87A
and 30. If OK, reinstall the relay and use a DRBIIIt
scan tool to perform further testing. Refer to the
appropriate diagnostic information.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the cover from the Power Distribution
Center (PDC) (Fig. 27).
(3) Remove the wiper high/low relay by grasping it
firmly and pulling it straight out from the receptacle
in the PDC.
INSTALLATION
(1) Position the wiper high/low relay to the proper
receptacle in the Power Distribution Center (PDC)
(Fig. 27).
(2) Align the wiper high/low relay terminals with
the terminal cavities in the PDC receptacle.
(3) Push firmly and evenly on the top of the wiper
high/low relay until the terminals are fully seated in
the terminal cavities in the PDC receptacle.
(4) Reinstall the cover onto the PDC.
(5) Reconnect the battery negative cable.
Fig. 26 ISO Micro Relay
30 - COMMON FEED
85 - COIL GROUND
86 - COIL BATTERY
87 - NORMALLY OPEN
87A - NORMALLY CLOSED
Fig. 27 Power Distribution Center
1 - FUEL PUMP RELAY
2 - STARTER MOTOR RELAY
3 - BLOWER MOTOR RELAY
4 - A/C COMPRESSOR CLUTCH RELAY
5 - OXYGEN SENSOR DOWNSTREAM RELAY
6 - AUTO SHUT DOWN RELAY
7-SPARE
8-SPARE
9a - (M/T) CLUTCH INTERLOCK RELAY
9b - (A/T) TRANSMISSION CONTROL RELAY
10 - SPARE
11 - WIPER HIGH/LOW RELAY
12 - WIPER ON/OFF RELAY
8R - 24 FRONT WIPERS/WASHERSKJ
WIPER HIGH/LOW RELAY (Continued)

DIAGNOSIS AND TESTING - WIPER ON/OFF
RELAY
The wiper on/off relay (Fig. 29) is located in the
Power Distribution Center (PDC) in the engine com-
partment near the battery. Refer to the appropriate
wiring information. The wiring information includes
wiring diagrams, proper wire and connector repair
procedures, details of wire harness routing and
retention, connector pin-out information and location
views for the various wire harness connectors, splices
and grounds.
(1) Remove the wiper on/off relay from the PDC.
(Refer to 8 - ELECTRICAL/WIPERS/WASHERS/
WIPER ON/OFF RELAY - REMOVAL).
(2) A relay in the de-energized position should
have continuity between terminals 87A and 30, and
no continuity between terminals 87 and 30. If OK, go
to Step 3. If not OK, replace the faulty relay.
(3) Resistance between terminals 85 and 86 (elec-
tromagnet) should be 75   8 ohms. If OK, go to Step
4. If not OK, replace the faulty relay.
(4) Connect a battery to terminals 85 and 86.
There should now be continuity between terminals
30 and 87, and no continuity between terminals 87A
and 30. If OK, reinstall the relay and use a DRBIIIt
scan tool to perform further testing. Refer to the
appropriate diagnostic information.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the cover from the Power Distribution
Center (PDC) (Fig. 30).
(3) Remove the wiper on/off relay by grasping it
firmly and pulling it straight out from the receptacle
in the PDC.
INSTALLATION
(1) Position the wiper on/off relay to the proper
receptacle in the Power Distribution Center (PDC)
(Fig. 30).
(2) Align the wiper on/off relay terminals with the
terminal cavities in the PDC receptacle.
(3) Push firmly and evenly on the top of the wiper
on/off relay until the terminals are fully seated in the
terminal cavities in the PDC receptacle.
(4) Reinstall the cover onto the PDC.
(5) Reconnect the battery negative cable.
Fig. 29 ISO Micro Relay
30 - COMMON FEED
85 - COIL GROUND
86 - COIL BATTERY
87 - NORMALLY OPEN
87A - NORMALLY CLOSED
Fig. 30 Power Distribution Center
1 - FUEL PUMP RELAY
2 - STARTER MOTOR RELAY
3 - BLOWER MOTOR RELAY
4 - A/C COMPRESSOR CLUTCH RELAY
5 - OXYGEN SENSOR DOWNSTREAM RELAY
6 - AUTO SHUT DOWN RELAY
7-SPARE
8-SPARE
9a - (M/T) CLUTCH INTERLOCK RELAY
9b - (A/T) TRANSMISSION CONTROL RELAY
10 - SPARE
11 - WIPER HIGH/LOW RELAY
12 - WIPER ON/OFF RELAY
8R - 26 FRONT WIPERS/WASHERSKJ
WIPER ON/OFF RELAY (Continued)

(5) Connect the test set hose or probe to the open
end of the leaking circuit. The test set gauge should
return to the 27 kPa (8 in. Hg.) setting shortly after
each connection is made. If OK, replace the faulty
disconnected component. If not OK, go to Step 6.
(6)
To locate a leak in a vacuum line, leave one end
of the line plugged and connect the test set hose or
probe to the other end of the line. Run your fingers
slowly along the line while watching the test set gauge.
The vacuum reading will fluctuate when your fingers
contact the source of the leak. To repair the vacuum
line, cut out the leaking section of the line. Then, insert
the loose ends of the line into a suitable length of 3 mil-
limeter (0.125 inch) inside diameter rubber hose.
STANDARD PROCEDURE - DIODE
REPLACEMENT
(1) Disconnect the battery negative cable and iso-
late it.
(2) Locate the diode in the harness, and remove
the protective covering.
(3) Remove the diode from the harness, pay atten-
tion to the current flow direction (Fig. 5).
(4) Remove the insulation from the wires in the
harness. Only remove enough insulation to solder in
the new diode.
(5) Install the new diode in the harness, making
sure current flow is correct. If necessary refer to the
appropriate wiring diagram for current flow.
(6) Solder the connection together using rosin core
type solder only.Do not use acid core solder.
(7) Tape the diode to the harness using electrical
tape making, sure the diode is completely sealed
from the elements.
(8) Re-connect the battery negative cable, and test
affected systems.
SPECIFICATIONS
A/C APPLICATION TABLE
Item Description Notes
Vehicle KJ- Liberty
System R134a w/ fixed
orifice tube
Compressor Sanden PXF-18 SP-10 PAG oil
Freeze±up
ControlA/C low
pressure switchaccumulator
mounted
Low psi Control opens < 25 psi
- resets > 43
psi
High psi Control switch - opens
> 450-490 psi -
resets <
270-330 psidischarge line
Control Head manual type
Mode Door vacuum
Blend Door electric
Recirculation
Doorvacuum
Blower Motor hardwired to
control headresistor block
Cooling Fan viscous for
cooling, single
speed electric
for A/C
Clutch Electro-
mechanical
Control relay PCM
Draw 2 - 3.7 amps @
12V  0.5V @ 70É F
Gap 0.0169- 0.0319
DRB IIIT
Reads TPS, RPM, A/C
switch test
Actuators clutch and fan
relay
Fig. 5 DIODE IDENTIFICATION
1 - CURRENT FLOW
2 - BAND AROUND DIODE INDICATES CURRENT FLOW
3 - DIODE AS SHOWN IN THE DIAGRAMS
KJHEATING & AIR CONDITIONING 24 - 9
HEATING & AIR CONDITIONING (Continued)

A/C COMPRESSOR CLUTCH
DESCRIPTION - 3.7L and 2.4L
The compressor clutch assembly consists of a sta-
tionary electromagnetic coil, a rotor bearing and
rotor assembly, and a clutch plate (Fig. 1). The elec-
tromagnetic coil unit and the rotor bearing and rotor
assembly are each retained on the nose of the com-
pressor front housing with snap rings. The clutch
plate is keyed to the compressor shaft and secured
with a nut. These components provide the means to
engage and disengage the compressor from the
engine serpentine accessory drive belt.
OPERATION - 3.7L and 2.4L
When the clutch coil is energized, it magnetically
draws the clutch into contact with the rotor and
drives the compressor shaft. When the coil is not
energized, the rotor freewheels on the clutch rotor
bearing, which is part of the rotor. 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 Heater mode control
switch, the A/C low pressure switch, the A/C high
pressure switch, the compressor clutch relay, 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 - A/C COMPRESSOR
CLUTCH COIL
For circuit descriptions and diagrams, (Refer to
Appropriate Wiring Information). 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, 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 DRB IIItscan tool and (Refer to
Appropriate Diagnostic Information) for testing of the
compressor clutch circuit and PCM control. The fol-
lowing 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
²Compressor clutch relay
²A/C high pressure switch
²A/C low pressure switch
²Powertrain Control Module (PCM).
(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.
STANDARD PROCEDURE - A/C COMPRESSOR
CLUTCH BREAK-IN
After a new compressor clutch has been installed,
cycle the compressor clutch approximately twenty
times (five seconds on, then five seconds off). During
this procedure, set the A/C Heater control to the
Recirculation Mode, the blower motor switch in the
highest speed position, and the engine speed at 1500
Fig. 1 COMPRESSOR CLUTCH - TYPICAL
1 - CLUTCH PLATE
2 - NOT USED ON KJ
3 - ROTOR
4 - COIL
5 - CLUTCH SHIMS
6 - SNAP RING
7 - SNAP RING
24 - 12 CONTROLSKJ

(2) Resistance between terminals 85 and 86 (elec-
tromagnet) should be 67.5 to 82.5 ohms. If OK, go to
Step 3. If not OK, replace the faulty relay.
(3) Connect a battery to terminals 85 and 86.
There should now be continuity between terminals
30 and 87, and no continuity between terminals 87A
and 30. If OK, see Relay Circuit Test. If not OK,
replace the faulty relay.
RELAY CIRCUIT TEST
For circuit descriptions and diagrams, (Refer to
Appropriate Wiring Information).
(1) The relay common feed terminal cavity (30) is
connected to fused battery feed. There should be bat-
tery voltage at the cavity for relay terminal 30 at all
times. If OK, go to Step 2. If not OK, repair the open
circuit to the fuse in the PDC as required.
(2) The relay normally closed terminal (87A) is not
used in this application. Go to Step 3.
(3) The relay normally open terminal cavity (87) is
connected to the compressor clutch coil. There should
be continuity between this cavity and the A/C com-
pressor clutch relay output circuit cavity of the com-
pressor clutch coil wire harness connector. If OK, go
to Step 4. If not OK, repair the open circuit as
required.
(4) The relay coil battery terminal (86) is con-
nected to the fused ignition switch output (run/start)circuit. There should be battery voltage at the cavity
for relay terminal 86 with the ignition switch in the
On position. If OK, go to Step 5. If not OK, repair the
open circuit to the fuse in the junction block as
required.
(5) The coil ground terminal cavity (85) is switched
to ground through the Powertrain Control Module
(PCM). There should be continuity between this cav-
ity and the A/C compressor clutch relay control cir-
cuit cavity of the PCM wire harness connector C
(gray) at all times. If not OK, repair the open circuit
as required.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the cover from the Power Distribution
Center (PDC).
(3) Refer to the label on the PDC for compressor
clutch relay identification and location.
(4) Unplug the compressor clutch relay from the
PDC.
INSTALLATION
(1) Install the compressor clutch relay by aligning
the relay terminals with the cavities in the PDC and
pushing the relay firmly into place.
(2) Install the PDC cover.
(3) Connect the battery negative cable.
(4) Test the relay operation.
A/C HEATER CONTROL
DESCRIPTION
Both the heater-only and A/C heater systems use a
combination of mechanical, electrical, and vacuum
controls. These controls provide the vehicle operator
with a number of setting options to help control the
climate and comfort within the vehicle. Refer to the
owner's manual in the vehicle glove box for more
information on the features, use, and suggested oper-
ation of these controls.
The heater-only or A/C heater control panel is
located to the right of the instrument cluster on the
instrument panel. The control panel contains a rota-
ry-type temperature control knob, a rotary-type mode
control switch knob, and a rotary-type blower motor
speed switch knob. The control also has a push but-
ton to activate the rear window defogger.
The heater-only or A/C heater control panel cannot
be repaired. If faulty or damaged, the entire unit
must be replaced. The illumination lamps are avail-
able for service replacement.
Fig. 10 COMPRESSOR CLUTCH RELAY
30 - COMMON FEED
85 - COIL GROUND
86 - COIL BATTERY
87 - NORMALLY OPEN
87A - NORMALLY CLOSED
24 - 16 CONTROLSKJ
A/C COMPRESSOR CLUTCH RELAY (Continued)

electric cooling fan operations. The switch is located
on the discharge line near the compressor. The
switch is screwed onto a fitting that contains a
Schrader-type valve, which allows the switch to be
serviced without discharging the refrigerant system.
The discharge line fitting is equipped with an O-ring
to seal the switch connection.
OPERATION
The A/C high pressure switch is connected in series
electrically with the A/C low pressure switch between
ground and the Powertrain Control Module (PCM).
The switch contacts open and close causing the PCM
to turn the compressor clutch on and off. This pre-
vents compressor operation when the discharge line
pressure approaches high levels, and also reduces
electrical surging from compressor clutch engage-
ment.
The A/C high pressure switch controls the electric
cooling fan operation by monitoring refrigerant line
pressures. When the discharge line pressure rises
above 1900 to 2200 kPa (280 to 320 psi) the fan will
turn on. The cooling fan will turn off when the dis-
charge line pressure drops to 1600 kPa (235 psi).
The A/C high pressure switch controls the A/C
clutch operation by disengaging the clutch when the
discharge line pressure rises above 3100 to 3375 kPa
(450 to 490 psi). The switch contacts will close and
allow A/C clutch engagement when the discharge line
pressure drops to 1860 to 2275 kPa (270 to 330 psi).
The A/C high pressure switch is a factory-cali-
brated unit. The switch cannot be adjusted or
repaired and, if faulty or damaged, it must be
replaced.
DIAGNOSIS AND TESTING - A/C HIGH
PRESSURE SWITCH
Before performing diagnosis of the A/C high pres-
sure switch, verify that the refrigerant system has
the correct refrigerant charge. (Refer to 24 - HEAT-
ING & AIR CONDITIONING/PLUMBING - STAN-
DARD PROCEDURE - REFRIGERANT SYSTEM
CHARGE)
For circuit descriptions and diagrams, (Refer to
Appropriate Wiring Information).
(1) Disconnect and isolate the battery negative
cable.
(2) Unplug the A/C high pressure switch wire har-
ness connector from the switch on the refrigerant
system fitting.
(3) On the four terminal A/C high pressure switch,
check for continuity between terminals C and D. On
the two terminal A/C high pressure switch, check for
continuity between both terminals of the switch.
There should be continuity. If OK, test and repair theA/C switch sense circuit as required. If not OK,
replace the faulty switch.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Unplug the wire harness connector from the
A/C high pressure switch, which is mounted to a fit-
ting on the non-flexible section of the discharge line
nearest the compressor.
(3) Unscrew the A/C high pressure switch from the
discharge line fitting.
(4) Remove the A/C high pressure switch from the
vehicle.
(5) Remove the O-ring seal from the discharge line
fitting and discard.
INSTALLATION
(1) Lubricate a new O-ring seal with clean refrig-
erant oil and install it on the discharge line fitting.
Use only the specified O-rings as they are made of a
special material for the R-134a system. Use only
refrigerant oil of the type recommended for the com-
pressor in the vehicle(Refer to 24 - HEATING & AIR
CONDITIONING - SPECIFICATIONS). (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING/RE-
FRIGERANT OIL - DESCRIPTION)
(2) Install and tighten the a/c high pressure switch
on the discharge line fitting. The switch should be
hand-tightened onto the discharge line fitting.
(3) Plug the wire harness connector into the a/c
high pressure switch.
(4) Connect the battery negative cable.
A/C LOW PRESSURE SWITCH
DESCRIPTION
The a/c low pressure switch is located on the top of
the accumulator. The switch is screwed onto an accu-
mulator fitting that contains a Schrader-type valve,
which allows the switch to be serviced without dis-
charging the refrigerant system. The accumulator fit-
ting is equipped with an O-ring to seal the switch
connection.
OPERATION
The a/c low pressure switch is connected in series
electrically with the a/c high pressure switch,
between ground and the Powertrain Control Module
(PCM). The switch contacts open and close causing
the PCM to turn the a/c compressor clutch on and
off. This regulates the refrigerant system pressure
and controls evaporator temperature. Controlling the
evaporator temperature prevents condensate water
24 - 18 CONTROLSKJ
A/C HIGH PRESSURE SWITCH (Continued)

on the evaporator fins from freezing and obstructing
air conditioning system air flow.
The a/c low pressure switch contacts are open
when the suction pressure is approximately 141 kPa
(20.5 psi) or lower. The switch contacts will close
when the suction pressure rises to approximately 234
to 262 kPa (34 to 38 psi) or above. Lower ambient
temperatures, below approximately -1É C (30É F), will
also cause the switch contacts to open. This is due to
the pressure/temperature relationship of the refriger-
ant in the system.
The a/c low pressure switch is a factory-calibrated
unit. It cannot be adjusted or repaired and, if faulty
or damaged, it must be replaced.
DIAGNOSIS AND TESTING - A/C LOW
PRESSURE SWITCH
Before performing diagnosis of the a/c low pressure
switch, be certain that the switch is properly
installed on the accumulator fitting. If the switch is
too loose it may not open the Schrader-type valve in
the accumulator fitting, which will prevent the
switch from correctly monitoring the refrigerant sys-
tem pressure. Remember that lower ambient temper-
atures, below about -1É C (30É F), during cold
weather will open the switch contacts and prevent
compressor operation due to the pressure/tempera-
ture relationship of the refrigerant.
Also verify that the refrigerant system has the cor-
rect refrigerant charge. (Refer to 24 - HEATING &
AIR CONDITIONING - DIAGNOSIS AND TESTING
- A/C PERFORMANCE) and (Refer to 24 - HEATING
& AIR CONDITIONING/PLUMBING - SPECIFICA-
TIONS).
For circuit descriptions and diagrams, (Refer to
Appropriate Wiring Information).
(1) Disconnect and isolate the battery negative
cable.
(2) Unplug the a/c low pressure switch wire har-
ness connector from the switch on the accumulator
fitting.
(3) Install a jumper wire between the two cavities
of the a/c low pressure switch wire harness connector.
(4) Connect a manifold gauge set to the refrigerant
system service ports. (Refer to 24 - HEATING & AIR
CONDITIONING/PLUMBING - STANDARD PRO-
CEDURE - REFRIGERANT SYSTEM SERVICE
EQUIPMENT) and (Refer to 24 - HEATING & AIR
CONDITIONING - DESCRIPTION - REFRIGERANT
SYSTEM SERVICE PORT)
(5) Connect the battery negative cable.
(6) Place the A/C Heater mode control switch knob
in any A/C position and start the engine.
(7) Check for continuity between the two terminals
of the a/c low pressure switch. There should be con-
tinuity with a suction pressure reading of 262 kPa(38 psi) or above, and no continuity with a suction
pressure reading of 141 kPa (20.5 psi) or below. If
OK, test and repair the A/C switch sense circuit as
required. If not OK, replace the faulty switch.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Unplug the wire harness connector from the a/c
low pressure switch on the top of the accumulator
(Fig. 13).
(3) Unscrew the a/c low pressure switch from the
fitting on the top of the accumulator.
(4) Remove the O-ring seal from the accumulator
fitting and discard.
INSTALLATION
(1) Lubricate a new O-ring seal with clean refrig-
erant oil and install it on the accumulator fitting.
Use only the specified O-rings as they are made of a
special material for the R-134a system. Use only
refrigerant oil of the type recommended for the com-
pressor in the vehicle. (Refer to 24 - HEATING &
AIR CONDITIONING/PLUMBING/REFRIGERANT
OIL - DESCRIPTION)
Fig. 13 A/C LOW PRESSURE SWITCH
1 - WIRING HARNESS CONNECTOR
2 - A/C LOW PRESSURE SWITCH
3 - A/C LINE TO EVAPORATOR
4 - ACCUMULATOR MOUNTING BRACKET
5 - ACCUMULATOR
6 - A/C LOW PRESSURE LINE
KJCONTROLS 24 - 19
A/C LOW PRESSURE SWITCH (Continued)