2002 JEEP LIBERTY actuator

DIAGNOSIS AND TESTING - HEATER
PERFORMANCE
Before performing the following tests, refer to Cool-
ing for the procedures to check the radiator coolant
level, serpentine drive belt tension, radiator air flow
and the radiator fan operation. Also be certain that
the accessory vacuum supply line is connected at the
engine intake manifold.
MAXIMUM HEATER OUTPUT
Engine coolant is delivered to the heater core
through two heater hoses. With the engine idling atnormal operating temperature, set the temperature
control knob in the full hot position, the mode control
switch knob in the floor heat position, and the blower
motor switch knob in the highest speed position.
Using a test thermometer, check the temperature of
the air being discharged at the HVAC housing floor
outlets. Compare the test thermometer reading to the
Temperature Reference chart.
Temperature Reference
Ambient Air Temperature15.5É C
(60É F)21.1É C
(70É F)26.6É C
(80É F)32.2É C
(90É F)
Minimum Air Temperature at
Floor Outlet52.2É C
(126É F)56.1É C
(133É F)59.4É C
(139É F)62.2É C
(144É F)
If the floor outlet air temperature is too low, refer
to Cooling to check the engine coolant temperature
specifications. Both of the heater hoses should be hot
to the touch. The coolant return heater hose should
be slightly cooler than the coolant supply heater
hose. If the return hose is much cooler than the sup-
ply hose, locate and repair the engine coolant flow
obstruction in the cooling system. Refer to Cooling
for the procedures.
OBSTRUCTED COOLANT FLOW Possible loca-
tions or causes of obstructed coolant flow:
²Pinched or kinked heater hoses.
²Improper heater hose routing.
²Plugged heater hoses or supply and return ports
at the cooling system connections.
²A plugged heater core.
If proper coolant flow through the cooling system is
verified, and heater outlet air temperature is still
low, a mechanical problem may exist.
MECHANICAL PROBLEMS Possible locations or
causes of insufficient heat:
²An obstructed cowl air intake.
²Obstructed heater system outlets.
²A blend door not functioning properly.
TEMPERATURE CONTROL
If the heater outlet air temperature cannot be
adjusted with the temperature control knob on theA/C Heater control panel, the following could require
service:
²The A/C Heater control.
²The blend door actuator.
²The blend door.
²Improper engine coolant temperature.
DIAGNOSIS AND TESTING - VACUUM SYSTEM
Vacuum control is used to operate the mode doors
in the heater-only and a/c heater housings. Testing of
the heater-only and A/C Heater mode control switch
operation will determine if the vacuum, electrical,
and mechanical controls are functioning. However, it
is possible that a vacuum control system that oper-
ates perfectly at engine idle (high engine vacuum)
may not function properly at high engine speeds or
loads (low engine vacuum). This can be caused by
leaks in the vacuum system, or a faulty vacuum
check valve.
A vacuum system test will help to identify the
source of poor vacuum system performance or vac-
uum system leaks. Before starting this test, stop the
engine and make certain that the problem is not a
disconnected vacuum supply tube at the engine
intake manifold vacuum tap or at the vacuum reser-
voir.
24 - 6 HEATING & AIR CONDITIONINGKJ
HEATING & AIR CONDITIONING (Continued)

Use an adjustable vacuum test set (Special Tool
C-3707-B) and a suitable vacuum pump to test the
HVAC vacuum control system. With a finger placed
over the end of the vacuum test hose probe (Fig. 3),
adjust the bleed valve on the test set gauge to obtain
a vacuum of exactly 27 kPa (8 in. Hg.). Release and
block the end of the probe several times to verify that
the vacuum reading returns to the exact 27 kPa (8
in. Hg.) setting. Otherwise, a false reading will be
obtained during testing.
VACUUM CHECK VALVE
(1) Remove the vacuum check valve. The valve is
located in the vacuum supply tube (black) at the
HVAC system vacuum tee.
(2) Connect the test set vacuum supply hose to the
A/C Heater Control side of the valve. When con-
nected to this side of the check valve, no vacuum
should pass and the test set gauge should return to
the 27 kPa (8 in. Hg.) setting. If OK, go to Step 3. If
not OK, replace the faulty valve.
(3) Connect the test set vacuum supply hose to the
engine vacuum side of the valve. When connected to
this side of the check valve, vacuum should flow
through the valve without restriction. If not OK,
replace the faulty valve.
A/C HEATER CONTROLS
(1) Connect the test set vacuum probe to the
HVAC vacuum supply (black) tube at the tee in the
engine compartment. Position the test set gauge so
that it can be viewed from the passenger compart-
ment.(2) Place the A/C Heater Mode Control switch
knob in each mode position, one position at a time,
and pause after each selection. The test set gauge
should return to the 27 kPa (8 in. Hg.) setting
shortly after each selection is made. If not OK, a
component or vacuum line in the vacuum circuit of
the selected mode has a leak. See the procedure in
Locating Vacuum Leaks.
CAUTION: Do not use lubricant on the switch ports
or in the holes in the plug, as lubricant will ruin the
vacuum valve in the switch. A drop of clean water
in the connector plug holes will help the connector
slide onto the switch ports.
LOCATING VACUUM LEAKS
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Disconnect the vacuum harness connector from
the back of the HVAC control head(Refer to 24 -
HEATING & AIR CONDITIONING/CONTROLS/A/C
HEATER CONTROL - REMOVAL).
(2) Connect the test set vacuum hose probe to each
port in the HVAC housing half of the vacuum har-
ness connector, one port at a time, and pause after
each connection. The test set gauge should return to
the 27 kPa (8 in. Hg.) setting shortly after each con-
nection is made. If OK, replace the faulty A/C Heater
Control. If not OK, go to Step 3.
(3) Determine the vacuum line color of the vacuum
circuit that is leaking. To determine the vacuum line
colors, refer to the Vacuum Circuits chart (Fig. 4).
(4) Disconnect and plug the vacuum line from the
component (fitting, actuator, valve, switch, or reser-
voir) on the other end of the leaking circuit. Instru-
ment panel disassembly or removal may be necessary
to gain access to some components. See the appropri-
ate service procedures.
Fig. 3 ADJUST VACUUM TEST BLEED VALVE
1 - VACUUM PUMP TOOL C-4289
2 - VACUUM TEST SET C-3707
3 - BLEED VALVE
4 - PROBE
KJHEATING & AIR CONDITIONING 24 - 7
HEATING & AIR CONDITIONING (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)

SPECIFICATIONS
TORQUE SPECIFICATIONS
DESCRIPTION N´m Ft. Lbs. In. Lbs.
A/C COMPRESSOR CLUTCH PLATE NUT 14.4 10.5 127.4
A/C COMPRESOR LINE MANIFOLD FASTENER 28 ( 6) 21 ( 4) 250 ( 50)
A/C COMPRESSOR TO MOUNTING BRACKET
BOLTS - 3.7L and 2.4L27 20 239
A/C COMPRESSOR TO MOUNTING BRACKET
BOLTS - 2.5L DIESEL33 25 292
ACCUMULATOR RETAINING BAND 5 3.7 44
BLEND DOOR ACTUATOR SCREWS 2.4 ( .34) 1.8 ( .25) 21 ( 3)
HVAC HOUSING SCREWS 2.4 ( .34) 1.8 ( .25) 21 ( 3)
HVAC HOUSING TO DASH PANEL NUTS 6.2 4.6 55
SUCTION LINE TO ACCUMULATOR FITTING 9 6.6 80
24 - 10 HEATING & AIR CONDITIONINGKJ
HEATING & AIR CONDITIONING (Continued)

CONTROLS
TABLE OF CONTENTS
page page
A/C COMPRESSOR CLUTCH
DESCRIPTION - 3.7L and 2.4L.............12
OPERATION - 3.7L and 2.4L...............12
DIAGNOSIS AND TESTING - A/C
COMPRESSOR CLUTCH COIL...........12
STANDARD PROCEDURE - A/C
COMPRESSOR CLUTCH BREAK-IN.......12
REMOVAL.............................13
INSPECTION..........................14
INSTALLATION.........................14
A/C COMPRESSOR CLUTCH RELAY
DESCRIPTION.........................15
OPERATION...........................15
DIAGNOSIS AND TESTING - COMPRESSOR
CLUTCH RELAY......................15
REMOVAL.............................16
INSTALLATION.........................16
A/C HEATER CONTROL
DESCRIPTION.........................16
REMOVAL.............................17
INSTALLATION.........................17
A/C HIGH PRESSURE SWITCH
DESCRIPTION.........................17
OPERATION...........................18
DIAGNOSIS AND TESTING - A/C HIGH
PRESSURE SWITCH...................18
REMOVAL.............................18
INSTALLATION.........................18
A/C LOW PRESSURE SWITCH
DESCRIPTION.........................18
OPERATION...........................18
DIAGNOSIS AND TESTING - A/C LOW
PRESSURE SWITCH...................19
REMOVAL.............................19
INSTALLATION.........................19
BLEND DOOR ACTUATOR
REMOVAL.............................20
INSTALLATION.........................20BLOWER MOTOR RELAY
DESCRIPTION.........................20
OPERATION...........................20
DIAGNOSIS AND TESTING - BLOWER
MOTOR RELAY.......................21
REMOVAL.............................21
INSTALLATION.........................22
BLOWER MOTOR RESISTOR
DESCRIPTION.........................22
OPERATION...........................22
DIAGNOSIS AND TESTING - BLOWER
MOTOR RESISTOR....................22
REMOVAL.............................22
INSTALLATION.........................22
BLOWER MOTOR SWITCH
DESCRIPTION.........................23
OPERATION...........................23
DIAGNOSIS AND TESTING - BLOWER
MOTOR SWITCH......................23
REMOVAL.............................23
INSTALLATION.........................23
MODE DOOR ACTUATOR
REMOVAL
REMOVAL - PANEL DOOR ACTUATOR.....24
REMOVAL - FLOOR - DEFROST DOOR
ACTUATOR..........................24
INSTALLATION
INSTALLATION - PANEL DOOR ACTUATOR . 25
INSTALLATION - FLOOR - DEFROST DOOR
ACTUATOR..........................25
RECIRCULATION DOOR ACTUATOR
REMOVAL.............................26
INSTALLATION.........................26
VACUUM CHECK VALVE
DESCRIPTION.........................28
OPERATION...........................28
REMOVAL.............................28
INSTALLATION.........................28
KJCONTROLS 24 - 11

(2) Install and tighten the a/c low pressure switch
on the accumulator fitting. The switch should be
hand-tightened onto the accumulator fitting.
(3) Plug the wire harness connector into the a/c
low pressure switch.
(4) Connect the battery negative cable.
BLEND DOOR ACTUATOR
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove A/C housing from vehicle(Refer to 24 -
HEATING & AIR CONDITIONING/DISTRIBUTION/
HVAC HOUSING - REMOVAL).
(3) Remove the screws that secure the blend door
actuator to the top of the HVAC housing. (Fig. 14).
(4) Remove the blend door actuator.
INSTALLATION
(1) Install the blend door actuator in place.
(2) Install and tighten the screws that secure the
blend door actuator to the housing. Tighten the
mounting screws to 2.4 ( .34) N´m (21 ( 3) in. lbs.).
(3) Install the HVAC housing into the vehicle(Re-
fer to 24 - HEATING & AIR CONDITIONING/DIS-
TRIBUTION/HVAC HOUSING - INSTALLATION).
(4) Install the blend door actuator electrical con-
nector from the wiring harness through the glove
box.
(5) Connect the battery negative cable.
BLOWER MOTOR RELAY
DESCRIPTION
The blower motor relay is a International Stan-
dards Organization (ISO)-type relay. The relay is a
electromechanical device that switches battery cur-
rent from a fuse in the Power Distribution Center
(PDC) directly to the blower motor. The relay is ener-
gized when the relay coil is provided a voltage signal
by the ignition switch. (Refer to 24 - HEATING &
AIR CONDITIONING/CONTROLS/BLOWER
MOTOR RELAY - DIAGNOSIS AND TESTING)
OPERATION
The blower motor relay is installed in a wire har-
ness connector that is secured to the passenger side
outboard end of the HVAC housing in the passenger
compartment, next to the HVAC wire harness con-
nector.
The blower motor relay cannot be repaired and, if
faulty or damaged, it must be replaced.
Fig. 14 HEATER CORE REMOVAL/INSTALLATION
1 - HEATER CORE
2- MOUNTING SCREW HOLE
3- INLET AND OUTLET TUBES
4- VACUUM HARNESS
5- ACTUATOR SCREWS (3)
6- ELECTRIC BLEND DOOR ACTUATOR
7- MOUNTING SCREW HOLE
8- HEATER CORE RETAINER TABS (4)
24 - 20 CONTROLSKJ
A/C LOW PRESSURE SWITCH (Continued)

MODE DOOR ACTUATOR
REMOVAL
REMOVAL - PANEL DOOR ACTUATOR
WARNING: ON VEHICLES EQUIPPED WITH AIRBAGS,
DISABLE THE AIRBAG SYSTEM BEFORE ATTEMPT-
ING ANY STEERING WHEEL, STEERING COLUMN, OR
INSTRUMENT PANEL COMPONENT DIAGNOSIS OR
SERVICE. DISCONNECT AND ISOLATE THE BATTERY
NEGATIVE (GROUND) CABLE, THEN WAIT TWO MIN-
UTES FOR THE AIRBAG SYSTEM CAPACITOR TO DIS-
CHARGE BEFORE PERFORMING FURTHER
DIAGNOSIS OR SERVICE. THIS IS THE ONLY SURE
WAY TO DISABLE THE AIRBAG SYSTEM. FAILURE TO
TAKE THE PROPER PRECAUTIONS COULD RESULT
IN AN ACCIDENTAL AIRBAG DEPLOYMENT AND POS-
SIBLE PERSONAL INJURY.
(1)Disconnect and isolate the battery negative cable.
(2) Remove the instrument panel assembly from
the vehicle(Refer to 23 - BODY/INSTRUMENT
PANEL - REMOVAL).
(3) Unplug the vacuum harness connector from the
defrost door actuator (Fig. 16).(4) Insert a trim stick or another suitable wide
flat-bladed tool into the latch hole on the HVAC
housing actuator mount. Gently pry the actuator
latch while pulling firmly outwards on the actuator
to remove the actuator from the mount.
(5) Rotate and tilt the vacuum actuator as
required to disengage the hole on the end of the
actuator link from the hooked pin on the end of the
defrost door lever.
(6) Remove the defrost door vacuum actuator from
the vehicle.
REMOVAL - FLOOR - DEFROST DOOR
ACTUATOR
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN AN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the instrument panel assembly from
the vehicle(Refer to 23 - BODY/INSTRUMENT
PANEL - REMOVAL).
(3) Unplug the vacuum harness connector from the
floor door actuator (Fig. 17).
(4) Insert a trim stick or another suitable wide
flat-bladed tool into the latch hole on the HVAC
housing actuator mount. Gently pry the actuator
latch while pulling firmly outwards on the actuator
to remove the actuator from the mount. (Fig. 18)
(5) Rotate and tilt the vacuum actuator as
required to disengage the hole on the end of the
actuator link from the hooked pin on the end of the
floor door lever.
(6) Remove the floor door vacuum actuator from
the vehicle.
Fig. 16 HVAC DOOR VACUUM ACTUATORS
1 - VACUUM LINE AND CONNECTOR
2 - PANEL DOOR ACTUATOR
3 - VACUUM LINE AND CONNECTOR
4 - FLOOR-DEFROST DOOR ACTUATOR
5 - HVAC ASSEMBLY
24 - 24 CONTROLSKJ

INSTALLATION
INSTALLATION - PANEL DOOR ACTUATOR
(1) Install the defrost door vacuum actuator by
snapping it into place, engage the hole on the end of
the actuator link with the hooked pin on the end of
the panel/demist door lever.
(2) Plug in the vacuum harness connector to the
defrost door actuator.
(3) Install the instrument panel assembly in the
vehicle(Refer to 23 - BODY/INSTRUMENT PANEL/
INSTRUMENT PANEL ASSEMBLY - INSTALLA-
TION).
(4) Connect the battery negative cable.
INSTALLATION - FLOOR - DEFROST DOOR
ACTUATOR
(1) Engage the hole on the end of the actuator
link to the hooked pin. Install the floor-defrost door
vacuum actuator to the HVAC assembly. on the end
of the floor door lever.
(2) Install the floor door vacuum actuator to the
HVAC assembly.
(3) Install the instrument panel assembly into the
vehicle(Refer to 23 - BODY/INSTRUMENT PANEL/
INSTRUMENT PANEL ASSEMBLY - INSTALLA-
TION).
(4) Connect the battery negative cable.
Fig. 17 HVAC DOOR VACUUM ACTUATORS
1 - VACUUM LINE AND CONNECTOR
2 - PANEL DOOR ACTUATOR
3 - VACUUM LINE AND CONNECTOR
4 - FLOOR-DEFROST DOOR ACTUATOR
5 - HVAC ASSEMBLY
Fig. 18 VACUUM ACTUATOR REMOVE/INSTALL -
TYPICAL
1 - ACTUATOR MOUNT LATCH HOLE
2 - TRIM STICK
3 - ACTUATOR LATCH
KJCONTROLS 24 - 25
MODE DOOR ACTUATOR (Continued)