2002 JEEP LIBERTY ECO mode

SECURED ACCESS METHOD
The Secured Access method applies to all vehicles.
This method requires the use of a DRBIIItscan tool.
This method will also require that you have access to
the unique four-digit PIN code that was assigned to
the original SKIM. The PIN codemustbe used to
enter the Secured Access Mode in the SKIM. This
PIN number may be obtained from the vehicle owner,
from the original vehicle invoice, or from the
DaimlerChrysler Customer Center. Refer to the
appropriate diagnostic information for the proper
Secured Access method programming procedures.
CUSTOMER LEARN METHOD
The Customer Learn feature is only available on
domestic vehicles, or those vehicles which have a
U.S. country code designator. This programming
method also requires access to at least two valid Sen-
try Keys. If two valid Sentry Keys are not available,
or if the vehicle does not have a U.S. country code
designator, the Secured Access Methodmustbe used
to program new or additional valid keys to the SKIM.
The Customer Learn programming method proce-
dures are as follows:
(1) Obtain the blank Sentry Key(s) that are to be
programmed as valid keys for the vehicle. Cut the
blank key(s) to match the ignition switch lock cylin-
der mechanical key codes.
(2) Insert one of the two valid Sentry Keys into the
ignition switch and turn the ignition switch to the
On position.
(3) After the ignition switch has been in the On
position for longer than three seconds, but no more
than fifteen seconds, cycle the ignition switch back to
the Off position. Replace the first valid Sentry Key in
the ignition switch lock cylinder with the second
valid Sentry Key and turn the ignition switch back to
the On position. The second valid Sentry Key must
be inserted in the lock cylinder within fifteen seconds
of removing the first valid key.
(4) About ten seconds after the completion of Step
3, the SKIS indicator in the instrument cluster will
start to flash and a single audible chime tone will
sound to indicate that the system has entered the
Customer Learn programming mode.
(5) Within sixty seconds of entering the Customer
Learn programming mode, turn the ignition switch to
the Off position, replace the valid Sentry Key with a
blank Sentry Key transponder, and turn the ignition
switch back to the On position.
(6)
About ten seconds after the completion of Step 5,
a single audible chime tone will sound and the SKIS
indicator will stop flashing, stay on solid for three sec-
onds, then turn off to indicate that the blank Sentry
Key has been successfully programmed. The SKIS will
immediately exit the Customer Learn programmingmode and the vehicle may now be started using the
newly programmed valid Sentry Key.
Each of these steps must be repeated and com-
pleted in their entirety for each additional Sentry
Key that is to be programmed. If the above steps are
not completed in the given sequence, or within the
allotted time, the SKIS will exit the Customer Learn
programming mode and the programming will be
unsuccessful. The SKIS will also automatically exit
the Customer Learn programming mode if it sees a
non-blank Sentry Key transponder when it should
see a blank, if it has already programmed eight (8)
valid Sentry Keys, or if the ignition switch is turned
to the Off position for more than about fifty seconds.
NOTE: If an attempt is made to start the vehicle
while in the Customer Learn mode (SKIS indicator
flashing), the SKIS will respond as though the vehi-
cle were being started with an invalid key. In other
words, the engine will stall after about two seconds
of operation. No faults will be set.
NOTE: Once a Sentry Key has been programmed as
a valid key to a vehicle, it cannot be programmed
as a valid key for use on any other vehicle.
DOOR CYLINDER LOCK
SWITCH
DESCRIPTION
Vehicles manufactured for North American mar-
kets that are equipped with the optional Vehicle
Fig. 2 Door Cylinder Lock Switch
1 - SWITCH
2 - OUTSIDE DOOR HANDLE
3 - DOOR LOCK CYLINDER
KJVEHICLE THEFT SECURITY 8Q - 9
VEHICLE THEFT SECURITY (Continued)

TERMINOLOGY
This is a list of terms and definitions used in the
wiring diagrams.
LHD .................Left Hand Drive Vehicles
RHD................Right Hand Drive Vehicles
ATX . . Automatic Transmissions-Front Wheel Drive
MTX....Manual Transmissions-Front Wheel Drive
AT ....Automatic Transmissions-Rear Wheel Drive
MT .....Manual Transmissions-Rear Wheel Drive
SOHC...........Single Over Head Cam Engine
DOHC..........Double Over Head Cam Engine
Built-Up-Export........ Vehicles Built For Sale In
Markets Other Than North America
Except-Built-Up-Export . . Vehicles Built For Sale In
North America
DESCRIPTION - CIRCUIT INFORMATION
Each wire shown in the diagrams contains a code
which identifies the main circuit, part of the main
circuit, gage of wire, and color (Fig. 4).
WIRE COLOR CODE CHART
COLOR CODE COLOR
BL BLUE
BK BLACK
BR BROWN
DB DARK BLUE
DG DARK GREEN
GY GRAY
LB LIGHT BLUE
LG LIGHT GREEN
COLOR CODE COLOR
OR ORANGE
PK PINK
RD RED
TN TAN
VT VIOLET
WT WHITE
YL YELLOW
* WITH TRACER
DESCRIPTION - CIRCUIT FUNCTIONS
All circuits in the diagrams use an alpha/numeric
code to identify the wire and it's function. To identify
which circuit code applies to a system, refer to the
Circuit Identification Code Chart. This chart shows
the main circuits only and does not show the second-
ary codes that may apply to some models.
CIRCUIT IDENTIFICATION CODE CHART
CIRCUIT FUNCTION
A BATTERY FEED
B BRAKE CONTROLS
C CLIMATE CONTROLS
D DIAGNOSTIC CIRCUITS
E DIMMING ILLUMINATION
CIRCUITS
F FUSED CIRCUITS
G MONITORING CIRCUITS
(GAUGES)
H OPEN
I NOT USED
J OPEN
K POWERTRAIN CONTROL
MODULE
L EXTERIOR LIGHTING
M INTERIOR LIGHTING
N NOT USED
O NOT USED
P POWER OPTION (BATTERY
FEED)
Q POWER OPTIONS (IGNITION
FEED)
R PASSIVE RESTRAINT
S SUSPENSION/STEERING
T TRANSMISSION/TRANSAXLE/
TRANSFER CASE
Fig. 4 WIRE CODE IDENTIFICATION
1 - COLOR OF WIRE (LIGHT BLUE WITH YELLOW TRACER
2 - GAGE OF WIRE (18 GAGE)
3 - PART OF MAIN CIRCUIT (VARIES DEPENDING ON
EQUIPMENT)
4 - MAIN CIRCUIT IDENTIFICATION
KJ8W-01 WIRING DIAGRAM INFORMATION8Wa-01-5
WIRING DIAGRAM INFORMATION (Continued)

FUEL LEVEL SENDING UNIT /
SENSOR
DESCRIPTION
The fuel gauge sending unit (fuel level sensor) is
attached to the side of the fuel pump module. The
sending unit consists of a float, an arm, and a vari-
able resistor track (card).
OPERATION
The fuel pump module has 4 different circuits
(wires). Two of these circuits are used for the fuel
gauge sending unit for fuel gauge operation, and for
certain OBD II emission requirements. The other 2
wires are used for electric fuel pump operation.
For Fuel Gauge Operation:A constant current
source of approximately 32 milliamps is supplied to
the resistor track on the fuel gauge sending unit.
This is fed directly from the Powertrain Control Mod-
ule (PCM).NOTE: For diagnostic purposes, this
12V power source can only be verified with the
circuit opened (fuel pump module electrical
connector unplugged). With the connectors
plugged, output voltages will vary from about
0.6 volts at FULL, to about 8.6 volts at EMPTY
(about 8.6 volts at EMPTY for Jeep models, and
about 7.0 volts at EMPTY for Dodge Truck mod-
els).The resistor track is used to vary the voltage
(resistance) depending on fuel tank float level. As
fuel level increases, the float and arm move up,
which decreases voltage. As fuel level decreases, the
float and arm move down, which increases voltage.
The varied voltage signal is returned back to the
PCM through the sensor return circuit.
Both of the electrical circuits between the fuel
gauge sending unit and the PCM are hard-wired (not
multi-plexed). After the voltage signal is sent from
the resistor track, and back to the PCM, the PCM
will interpret the resistance (voltage) data and send
a message across the multi-plex bus circuits to the
instrument panel cluster. Here it is translated into
the appropriate fuel gauge level reading. Refer to
Instrument Panel for additional information.
For OBD II Emission Monitor Requirements:
The PCM will monitor the voltage output sent from
the resistor track on the sending unit to indicate fuel
level. The purpose of this feature is to prevent the
OBD II system from recording/setting false misfire
and fuel system monitor diagnostic trouble codes.
The feature is activated if the fuel level in the tank
is less than approximately 15 percent of its rated
capacity. If equipped with a Leak Detection Pump
(EVAP system monitor), this feature will also be acti-
vated if the fuel level in the tank is more than
approximately 85 percent of its rated capacity.
DIAGNOSIS AND TESTING - FUEL LEVEL
SENDING UNIT
The fuel level sending unit contains a variable
resistor (track). As the float moves up or down, elec-
trical resistance will change. Refer to Instrument
Panel and Gauges for Fuel Gauge testing. To test the
gauge sending unit only, it must be removed from
vehicle. The unit is a separate part of the lower fuel
pump module section. Refer to Fuel Pump Module
Removal/Installation for procedures (remove only the
upper section of the fuel pump module). Measure the
resistance across the sending unit terminals. With
float in up position, resistance should be 20 ohms (+/-
5%). With float in down position, resistance should be
270 ohms (+/- 5%).
REMOVAL
The fuel level sending unit (fuel level sensor) and
float assembly is located on the side of the lower sec-
tion of the fuel pump module. The lower section of
the fuel pump module is located within the fuel tank.
(1) Remove lower section of fuel pump module
from fuel tank. Refer to Fuel Pump Module Removal/
Installation.
(2) To remove sending unit from pump module, lift
on plastic locking tab (Fig. 8) while sliding sending
unit upwards.
(3) Disconnect 4±wire electrical connector (Fig. 9)
from bottom of upper section of fuel pump module.
Separate necessary sending unit wiring.
Fig. 8 FUEL LEVEL SENDING UNIT
1 - LIFT TAB HERE FOR REMOVAL
2 - FUEL LEVEL SENDING UNIT
3 - LOWER SECTION OF PUMP MODULE
KJFUEL DELIVERY 14 - 9

OPERATION
The fuel pressure regulator is a mechanical device
that is not controlled by engine vacuum or the Pow-
ertrain Control Module (PCM).
The regulator is calibrated to maintain fuel system
operating pressure of approximately 339 kPa +/- 34
kPa (49.2 psi +/- 5 psi) at the fuel injectors. It con-
tains a diaphragm, calibrated springs and a fuel
return valve.
The main fuel filteris not combinedwithin the
fuel pressure regulator as in other Jeeptmodels.
Three different fuel filters are used: 1. a serviceable,
separate, externally mounted, main fuel filter; 2. a
non-serviceable primary filter located on the bottom
of the electric fuel pump; 3. a non-serviceable second-
ary filter attached to the side of the fuel pump mod-
ule.
Fuel Flow:Fuel migrates into the fuel pump mod-
ule reservoir through a one-way check valve located
on the bottom of the module. This check valve pre-
vents the reservoir from running empty such as
when going up or down hills with a low amount of
fuel in the tank. A primary fuel filter (sock) is located
at the bottom of the electric fuel pump. Fuel is drawn
in through this filter, and up to the electric fuel
pump. High pressure fuel (unregulated) is supplied
from the electric fuel pump through a high-pressure
line to one of 3 fittings on the main fuel filter. If fuel
pressure at the pressure regulator exceeds approxi-
mately 49 psi, an internal diaphragm within the reg-
ulator closes, and excess fuel is routed through a
second fitting on the main fuel filter, and back into
the fuel tank (the fuel pressure regulator is installed
into the return side of the system). Pressure regu-
lated fuel is then delivered from the third fitting on
the fuel filter, up to and through the fuel rail, and on
to the fuel injectors.
A secondary fuel filter is attached to the side of the
fuel pump module. High-pressure from the electric
fuel pump causes a siphoning action across a passage
connected to this filter, and fuel is drawn into the
fuel pump module reservoir. This is used to help keep
the module reservoir full of fuel.
The fuel pressure regulator also acts as a check
valve to maintain some fuel pressure when the
engine is not operating. This will help to start the
engine. A second check valve is located at the outlet
of the fuel pump module housing.Refer to Fuel
Pump - Description and Operation for more
information. Also refer to the Fuel Pressure
Leak Down Test, and the Fuel Pump Pressure
Tests.
A separate fuel return line from the engine is not
used with this system.
REMOVAL
The fuel pressure regulator is located in the fuel
tank. It is attached to the bottom of the upper sec-
tion of the fuel pump module with a quick-connect
fitting (Fig. 19). The fuel pump module is supplied in
2 sections (upper and lower). To replace the pressure
regulator, the bottom section of the fuel pump mod-
ule must be replaced.
(1) Remove upper and lower sections of fuel pump
module from fuel tank. Refer to Fuel Pump Module
Removal/Installation.
(2) Replace lower section of fuel pump module
(includes fuel pressure regulator).
INSTALLATION
The fuel pressure regulator is located in the fuel
tank. It is attached to the bottom of the upper sec-
tion of the fuel pump module with a quick-connect
fitting. The fuel pump module is supplied in 2 sec-
tions (upper and lower). To replace the pressure reg-
ulator, the bottom section of the fuel pump module
must be replaced.
(1) Replace lower section of fuel pump module
(includes fuel pressure regulator).
(2) Install upper and lower sections of fuel pump
module to fuel tank. Refer to Fuel Pump Module
Installation.
Fig. 19 FUEL PRESSURE REGULATOR/SENDING
UNIT ELECTRICAL CONNECTOR
1 - UPPER SECTION OF PUMP MODULE
2 - QUICK-CONNECT FITTINGS
3 - FUEL PRESSURE REGULATOR
4 - 4-WIRE ELECTRICAL CONNECTOR
5 - FUEL TANK CHECK (CONTROL) VALVE
14 - 14 FUEL DELIVERYKJ
FUEL PRESSURE REGULATOR (Continued)

TIRES
DESCRIPTION
DESCRIPTION - TIRES
Tires are designed and engineered for each specific
vehicle. They provide the best overall performance
for normal operation. The ride and handling charac-
teristics match the vehicle's requirements. With
proper care they will give excellent reliability, trac-
tion, skid resistance, and tread life.
Driving habits have more effect on tire life than
any other factor. Careful drivers will obtain in most
cases, much greater mileage than severe use or care-
less drivers. A few of the driving habits which will
shorten the life of any tire are:
²Rapid acceleration
²Severe brake applications
²High speed driving
²Excessive speeds on turns
²Striking curbs and other obstacles
Radial-ply tires are more prone to irregular tread
wear. It is important to follow the tire rotation inter-
val,(Refer to 22 - TIRES/WHEELS - STANDARD
PROCEDURE). This will help to achieve a greater
tread life.
TIRE IDENTIFICATION
Tire type, size, aspect ratio and speed rating are
encoded in the letters and numbers imprinted on the
side wall of the tire. Refer to the chart to decipher
the tire identification code (Fig. 11).
Performance tires have a speed rating letter after
the aspect ratio number.
LETTER SPEED RATING
S 180 km/h (112 mph)
T 190 km/h (118 mph)
U 200 km/h (124 mph)
H 210 km/h (130 mph)
V 240 km/h (149 mph)
W 270 km/h (168 mph)
Y 300 km/h (186 mph)
The speed rating is not always printed on the tire
sidewall.
TIRE CHAINS
Tire snow chains may be used oncertainmodels.
Refer to the Owner's Manual for more information.
DESCRIPTION - RADIAL-PLY TIRES
Radial-ply tires improve handling, tread life and
ride quality, and decrease rolling resistance.
Radial-ply tires must always be used in sets of
four. Under no circumstances should they be used on
the front only. They may be mixed with temporary
spare tires when necessary. A maximum speed of 50
MPH is recommended while a temporary spare is in
use.
Radial-ply tires have the same load-carrying capac-
ity as other types of tires of the same size. They also
use the same recommended inflation pressures.
The use of oversized tires, either in the front or
rear of the vehicle, can cause vehicle drive train fail-
ure. This could also cause inaccurate wheel speed
signals when the vehicle is equipped with Anti-Lock
Brakes.
The use of tires from different manufactures on the
same vehicle is NOT recommended. The proper tire
pressure should be maintained on all four tires.
DESCRIPTION - SPARE TIRE &TEMPORARY
The temporary spare tire is designed for emer-
gency use only. The original tire should be repaired
or replaced at the first opportunity, then reinstalled.
Do not exceed speeds of 50 M.P.H. when using the
temporary spare tire. Refer to Owner's Manual for
complete details.
Fig. 11 Tire Identification
22 - 6 TIRES/WHEELSKJ

DESCRIPTION - REFRIGERANT SYSTEM
SERVICE PORT
The two refrigerant system service ports are used
to charge, recover/recycle, evacuate, and test the air
conditioning refrigerant system. Unique service port
coupler sizes are used on the R-134a system, to
ensure that the refrigerant system is not accidentally
contaminated by the use of the wrong refrigerant
(R-12), or refrigerant system service equipment.
OPERATION
OPERATION - HEATER AND AIR CONDITIONER
The heater and optional air conditioner are blend-
air type systems. In a blend-air system, a blend door
controls the amount of unconditioned air (or cooled
air from the evaporator on models with air condition-
ing) that is allowed to flow through, or around, the
heater core. A temperature control knob on the A/C
Heater control panel determines the discharge air
temperature by controlling an electric actuator,
which moves the blend door. This allows an almost
immediate control of the output air temperature of
the system.
The mode control knob on the heater-only or A/C
Heater control panel is used to direct the conditioned
air to the selected system outlets. Both mode control
switches use engine vacuum to control the mode
doors, which are operated by vacuum actuators.
On all vehicles, the outside air intake can be shut
off by selecting the Recirculation Mode with the
mode control knob. This will operate a vacuum actu-
ated recirculation door that closes off the outside
fresh air intake and recirculates the air that is
already inside the vehicle.
The optional air conditioner for all models is
designed for the use of non-CFC, R-134a refrigerant.
The air conditioning system has an evaporator to cool
and dehumidify the incoming air prior to blending it
with the heated air. This air conditioning system
uses a fixed orifice tube in the liquid line near the
condenser outlet tube to meter refrigerant flow to the
evaporator coil. To maintain minimum evaporator
temperature and prevent evaporator freezing, the
A/C low pressure switch on the accumulator cycles
the compressor clutch.
OPERATION - REFRIGERANT SYSTEM SERVICE
PORT
The high pressure service port is located on the
refrigerant line, near the discharge port of the com-
pressor. The low pressure service port is located on
the liquid line at the side of the engine compartment,
near the condensor.Each of the service ports has a threaded plastic
protective cap installed over it from the factory. After
servicing the refrigerant system, always reinstall
both of the service port caps.
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - A/C
PERFORMANCE
The air conditioning system is designed to provide
the passenger compartment with low temperature
and low humidity air. The evaporator, located in the
HVAC housing on the dash panel below the instru-
ment panel, is cooled to temperatures near the freez-
ing point. As warm damp air passes through the
cooled evaporator, the air transfers its heat to the
refrigerant in the evaporator and the moisture in the
air condenses on the evaporator fins. During periods
of high heat and humidity, an air conditioning sys-
tem will be more effective in the Recirculation Mode.
With the system in the Recirculation Mode, only air
from the passenger compartment passes through the
evaporator. As the passenger compartment air dehu-
midifies, the air conditioning system performance
levels improve.
Humidity has an important bearing on the temper-
ature of the air delivered to the interior of the vehi-
cle. It is important to understand the effect that
humidity has on the performance of the air condition-
ing system. When humidity is high, the evaporator
has to perform a double duty. It must lower the air
temperature, and it must lower the temperature of
the moisture in the air that condenses on the evapo-
rator fins. Condensing the moisture in the air trans-
fers heat energy into the evaporator fins and tubing.
This reduces the amount of heat the evaporator can
absorb from the air. High humidity greatly reduces
the ability of the evaporator to lower the temperature
of the air.
However, evaporator capacity used to reduce the
amount of moisture in the air is not wasted. Remov-
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 the
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.
Before proceeding, (Refer to 24 - HEATING & AIR
CONDITIONING/PLUMBING - WARNING) and
(Refer to 24 - HEATING & AIR CONDITIONING/
PLUMBING - CAUTION). The air temperature in
the test room and in the vehicle must be a minimum
of 21É C (70É F) for this test.
24 - 2 HEATING & AIR CONDITIONINGKJ
HEATING & AIR CONDITIONING (Continued)

(1) Connect a tachometer a manifold gauge set or
A/C recycling/charging station.
(2) Set the A/C Heater mode control switch knob in
the Recirculation Mode position, the temperature
control knob in the full cool position, and the blower
motor switch knob in the highest speed position.
(3) Start the engine and hold the idle at 1,000 rpm
with the compressor clutch engaged.
(4) The engine should be at operating temperature.
The doors and windows must be closed.
(5) Insert a thermometer in the driver side center
A/C (panel) outlet. Operate the engine for five min-
utes.
(6) The compressor clutch may cycle, depending
upon the ambient temperature and humidity. If the
clutch cycles, unplug the a/c low pressure switch wire
harness connector. (Fig. 2). Place a jumper wire
across the terminals of the a/c low pressure switch
wire harness connector.
(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 - SPECIFICATIONS -
CHARGE CAPACITY).
Performance Temperature and Pressure
Ambient Air
Temperature21É C
(70É F)27É C
(80É F)32É C
(90É F)38É C
(100É F)43É C
(110É F)
Air Temperature at
Center Panel Outlet7É C
(45É F)7É C
(45É F)13É C
(55É F)13É C
(55É F)18É C
(64É F)
Compressor Inlet
Pressure at Service
Port (low Side)138 to 207 kPa
(20 to 30 psi)172 to 241
kPa
(25 to 35 psi)207 to 276
kPa
(30 to 40 psi)241 to 310
kPa
(35 to 45 psi)276 to 345 kPa
(40 to 50 psi)
Condensor Out
Pressuree at Service
POrt (High Side)1034 to 1724
kPa
(150 to 250
psi)1379 to 2068
kPa
(200 to 300
psi)1724 to 2413
kPa
(250 to 350
psi)1999 to 2689
kPa
(290 to 390
psi)2413 to 2965
kPa
(350 to 430 psi)
(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.
Fig. 2 A/C LOW PRESSURE SWITCH - TYPICAL
1 - A/C LOW PRESSURE SWITCH
2 - ACCUMULATOR
KJHEATING & AIR CONDITIONING 24 - 3
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