C1 terminal DODGE RAM 2003 Service Repair Manual

(2) Remove fuel pump relay from Power Distribu-
tion Center (PDC). For location of relay, refer to label
on underside of PDC cover.
(3) Start and run engine until it stalls.
(4) Attempt restarting engine until it will no
longer run.
(5) Turn ignition key to OFF position.
CAUTION: Steps 1, 2, 3 and 4 must be performed to
relieve high pressure fuel from within fuel rail. Do
not attempt to use following steps to relieve this
pressure as excessive fuel will be forced into a cyl-
inder chamber.
(6) Unplug connector from any fuel injector.
(7) Attach one end of a jumper wire with alligator
clips (18 gauge or smaller) to either injector terminal.
(8) Connect other end of jumper wire to positive
side of battery.(9) Connect one end of a second jumper wire to
remaining injector terminal.
CAUTION: Powering an injector for more than a few
seconds will permanently damage the injector.
(10) Momentarily touch other end of jumper wire
to negative terminal of battery for no more than a
few seconds.
(11) Place a rag or towel below fuel line quick-con-
nect fitting at fuel rail.
(12) Disconnect quick-connect fitting at fuel rail.
Refer to Quick-Connect Fittings.
(13) Return fuel pump relay to PDC.
(14) One or more Diagnostic Trouble Codes (DTC's)
may have been stored in PCM memory due to fuel
pump relay removal. The DRBtscan tool must be
used to erase a DTC.
SPECIFICATIONS
FUEL SYSTEM PRESSURE
339 kPa +/- 34 kPa (49.2 psi +/- 2 psi).
TORQUE - FUEL SYSTEM
DESCRIPTION N-m Ft. Lbs. In. Lbs.
Accelerator Pedal Bracket
Mounting12 - 105
Accelerator Pedal Position
Sensor Bracket-to-Battery
Tray Bolts3-30
Crankshaft Position
Sensor - 3.7L28 21 -
Crankshaft Position
Sensor - 4.7L28 21 -
Crankshaft Position
Sensor - 5.7L12 - 105 (+/-20)
Crankshaft Position
Sensor - 5.9L8-70
Crankshaft Position
Sensor - 8.0L8-70
Camshaft Position Sensor
- 3.7L12 - 106
Camshaft Position Sensor
- 4.7L12 - 106
Camshaft Position Sensor
- 5.7L12 9 105 (+/-) 20
Camshaft Position Sensor
- 8.0L6-50
DRFUEL DELIVERY - GAS 14 - 3
FUEL DELIVERY - GAS (Continued)

pump.Refer to Fuel Pump - Description and
Operation for more information.
If fuel pressure at the pressure regulator exceeds
approximately 49.2 psi, an internal diaphragm opens
and excess fuel pressure is routed back into the tank
through the bottom of pressure regulator.
Both fuel filters (at bottom of fuel pump module
and within fuel pressure regulator) are designed for
extended service. They do not require normal sched-
uled maintenance. Filters should only be replaced if
a diagnostic procedure indicates to do so.
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 is supplied to the resistor track on the fuel
gauge sending unit. This is fed directly from the
Powertrain Control Module (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 models).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.
REMOVAL
The fuel level sending unit (fuel level sensor) and
float assembly is located on the side of the fuel pump
module (Fig. 3).
(1) Remove 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. 4) while sliding sending
unit tracks.
(3) Disconnect 4±wire electrical connector (Fig. 3)
from fuel pump module. Separate necessary sending
unit wiring from connector using terminal pick /
removal tool. Refer to Special Tools in 8W Wiring for
tool part numbers.
Fig. 3 LOCATION - FUEL GAUGE SENDING UNIT
1 - FUEL FILTER / FUEL PRESSURE REGULATOR
2 - FUEL PUMP MODULE ASSEMBLY
3 - 4-WAY ELEC. CONNECT.
4 - FLOAT ARM
5 - ELEC. FUEL PUMP
6 - INLET FILTER
7 - FUEL GAUGE SENDING UNIT
8 - GASKET (SEAL)
DRFUEL DELIVERY - GAS 14 - 7
FUEL FILTER/PRESSURE REGULATOR (Continued)

INSTALLATION
(1) Install fuel injector(s) into fuel rail assembly
and install retaining clip(s).
(2) If same injector(s) is being reinstalled, install
new o-ring(s).
(3) Apply a small amount of clean engine oil to
each injector o-ring. This will aid in installation.
(4) Install fuel rail. Refer to Fuel Rail Installation.
(5) Start engine and check for fuel leaks.
FUEL PUMP RELAY
DESCRIPTION
The 5±pin, 12±volt, fuel pump relay is located in
the Power Distribution Center (PDC). Refer to the
label on the PDC cover for relay location.
OPERATION
The Powertrain Control Module (PCM) energizes
the electric fuel pump through the fuel pump relay.
The fuel pump relay is energized by first applying
battery voltage to it when the ignition key is turned
ON, and then applying a ground signal to the relay
from the PCM.
Whenever the ignition key is turned ON, the elec-
tric fuel pump will operate. But, the PCM will shut-
down the ground circuit to the fuel pump relay in
approximately 1±3 seconds unless the engine is oper-
ating or the starter motor is engaged.
REMOVAL
The fuel pump relay is located in the Power Distri-
bution Center (PDC) (Fig. 19). Refer to label on PDC
cover for relay location.
(1) Remove PDC cover.
(2) Remove relay from PDC.
(3) Check condition of relay terminals and PDC
connector terminals for damage or corrosion. Repair
if necessary before installing relay.
(4) Check for pin height (pin height should be the
same for all terminals within the PDC connector).
Repair if necessary before installing relay.
INSTALLATION
The fuel pump relay is located in the Power Distri-
bution Center (PDC). Refer to label on PDC cover for
relay location.
(1) Install relay to PDC.
(2) Install cover to PDC.
IDLE AIR CONTROL MOTOR
DESCRIPTION
A separate IAC motor is not used with the 5.7L V-8
engine.
The IAC stepper motor is mounted to the throttle
body, and regulates the amount of air bypassing the
control of the throttle plate. As engine loads and
ambient temperatures change, engine rpm changes.
A pintle on the IAC stepper motor protrudes into a
passage in the throttle body, controlling air flow
through the passage. The IAC is controlled by the
Powertrain Control Module (PCM) to maintain the
target engine idle speed.
OPERATION
A separate IAC motor is not used with the 5.7L V-8
engine.
At idle, engine speed can be increased by retract-
ing the IAC motor pintle and allowing more air to
pass through the port, or it can be decreased by
restricting the passage with the pintle and diminish-
ing the amount of air bypassing the throttle plate.
The IAC is called a stepper motor because it is
moved (rotated) in steps, or increments. Opening the
IAC opens an air passage around the throttle blade
which increases RPM.
The PCM uses the IAC motor to control idle speed
(along with timing) and to reach a desired MAP dur-
ing decel (keep engine from stalling).
Fig. 19 PDC LOCATION
1 - BATTERY
2 - PDC (POWER DISTRIBUTION CENTER)
DRFUEL INJECTION - GAS 14 - 33
FUEL INJECTOR (Continued)

(c) Position new element to canister lid. Place
this assembly into canister by rotating clockwise.
(d) Tighten cap to 34 N´m (25 ft. lbs.) torque. Do
not overtighten cap.
(3)Water-In-Fuel (WIF) Sensor:
(a) Install new o-ring seal to WIF sensor.
(b) Apply a light film of clean diesel oil to o-ring
seal.
(c) Install sensor into housing.
(d) Tighten sensor to 4.5 N´m (39 in. lbs.) torque.
(e) Connect electrical connector to WIF sensor.
(4)Fuel Heater Element:
(a) Install fuel heater into fuel filter housing.
(b) Install fuel heater thermostat into fuel filter
housing.
(c) Install fuel heater mounting screws and
tighten to 1-1.5 N´m torque.
(d) Connect electrical connector to fuel heater
thermostat.
(e) Install new filter cover O-ring onto fuel filter
housing cover and lubricate with 30W oil.
(f) Tighten fuel filter housing cover (lid) to 34
N´m (25 ft. lbs.).
(5)Drain Valve:
(a) Install 2 new o-rings to valve and filter hous-
ing.
(b) Lubricate with silicon grease.
(c) Install fuel drain valve.
(d) Install 4 mounting screws and tighten to
1±1.5 N´m (8±13 in. lbs.) torque.
(e) Connect drain hose to drain valve.
(6) Start engine and check for leaks.
FUEL HEATER
DESCRIPTION
The fuel heater assembly is located on the side of
the fuel filter housing (Fig. 3) or (Fig. 4).
The heater/element assembly is equipped with a
temperature sensor (thermostat) that senses fuel
temperature. This sensor is attached to the fuel heat-
er/element assembly.
OPERATION
The fuel heater is used to prevent diesel fuel from
waxing during cold weather operation.
When the temperature is below 45  8 degrees F,
the temperature sensor allows current to flow to the
heater element warming the fuel. When the temper-
ature is above 75  8 degrees F, the sensor stops cur-
rent flow to the heater element.
Battery voltage to operate the fuel heater element
is supplied from the ignition switch and through the
fuel heater relay. Also refer to Fuel Heater Relay.The fuel heater element and fuel heater relay
are not computer controlled.
The heater element operates on 12 volts, 300 watts
at 0 degrees F.
DIAGNOSIS AND TESTING - FUEL HEATER
The fuel heater is used to prevent diesel fuel from
waxing during cold weather operation.
NOTE: The fuel heater element, fuel heater relay
and fuel heater temperature sensor are not con-
trolled by the Engine Control Module (ECM), or the
Powertrain Control Module (PCM).
A malfunctioning fuel heater can cause a wax
build-up in the fuel filter/water separator. Wax
build-up in the filter/separator can cause engine
starting problems and prevent the engine from rev-
ving up. It can also cause blue or white fog-like
exhaust. If the heater is not operating in cold tem-
peratures, the engine may not operate due to fuel
waxing.
The fuel heater assembly is located on the side of
fuel filter housing.
The heater assembly is equipped with a built-in
fuel temperature sensor (thermostat) that senses fuel
temperature. When fuel temperature drops below 45
degrees   8 degrees F, the sensor allows current to
flow to built-in heater element to warm fuel. When
fuel temperature rises above 75 degrees   8 degrees
F, the sensor stops current flow to heater element
(circuit is open).
Voltage to operate fuel heater element is supplied
from ignition switch, through fuel heater relay (also
refer to Fuel Heater Relay), to fuel temperature sen-
sor and on to fuel heater element.
The heater element operates on 12 volts, 300 watts
at 0 degrees F. As temperature increases, power
requirements decrease.
A minimum of 7 volts is required to operate fuel
heater. The resistance value of heater element is less
than 1 ohm (cold) and up to 1000 ohms warm.
TESTING
(1) Disconnect electrical connector from thermostat
(Fig. 3) or (Fig. 4).
Ambient temperature must be below circuit close
temperature, If necessary, induce this ambient tem-
perature by placing ice packs on thermostat to pro-
duce an effective ambient temperature below circuit
close temperature. For first check of thermostat you
can hear click of thermostat when circuit closes.
Measure resistance across two pins. Operating
range is 0.3 Ð 0.45 Ohms.
(2) If resistance is out of range, remove thermostat
and check resistance across terminal connections of
DRFUEL DELIVERY - DIESEL 14 - 63
FUEL FILTER / WATER SEPARATOR (Continued)

heater. The heater can be check at room tempera-
ture. Operating range is 0.3 Ð 0.45 Ohms.
(3) Replace heater if resistance is not within oper-
ating range.
(4) If heater is within operating range, replace
heater thermostat.
REMOVAL
REMOVAL/INSTALLATION
The fuel heater/element/sensor assembly is located
inside of the fuel filter housing. Refer to Fuel Filter/
Water Separator Removal/Installation for procedures.
FUEL HEATER RELAY
DESCRIPTION
The fuel heater relay is located in Power Distribu-
tion Center (PDC) (Fig. 6). Refer to label on inside of
PDC cover for relay location.
OPERATION
Battery voltage to operate the fuel heater element
is supplied from the ignition switch through the fuel
heater relay.The fuel heater element and fuel
heater relay are not computer controlled.
REMOVAL
The fuel heater relay is located in the Power Dis-
tribution Center (PDC) (Fig. 7). Refer to label under
PDC cover for relay location.
(1) Remove PDC cover.
(2) Remove relay from PDC.(3) Check condition of relay terminals and PDC
connector terminals for damage or corrosion. Repair
if necessary before installing relay.
(4) Check for pin height (pin height should be the
same for all terminals within the PDC connector).
Repair if necessary before installing relay.
INSTALLATION
The fuel heater relay is located in the Power Dis-
tribution Center (PDC) (Fig. 7). Refer to label under
PDC cover for relay location.
(1) Install relay to PDC.
(2) Install cover to PDC.
FUEL INJECTION PUMP
DESCRIPTION
A Robert Bosch high-pressure fuel injection pump
is used. The pump is attached to the back of the tim-
ing gear cover at the left / rear side of the engine.
OPERATION
The fuel injection pump supplies high pressure to
the fuel rail independent of engine speed. This high
pressure is then accumulated in the fuel rail. High
pressure fuel is constantly supplied to the injectors
by the fuel rail. The Engine Control Module (ECM)
controls the fueling and timing of the engine by actu-
ating the injectors.
Fuel enters the system from the electric fuel trans-
fer (lift) pump, which is attached to the fuel filter
assembly. Fuel is forced through the fuel filter ele-
ment and then enters the Fuel Pump/Gear Pump,
which is attached to the rear of the fuel injection
Fig. 6 POWER DISTRIBUTION CENTER LOCATION
1 - CLIP
2 - BATTERY
3 - TRAY
4 - NEGATIVE CABLE
5 - POSITIVE CABLE
6 - CLIP
7 - FENDER INNER SHIELD
8 - POWER DISTRIBUTION CENTER
Fig. 7 POWER DISTRIBUTION CENTER LOCATION
1 - CLIP
2 - BATTERY
3 - TRAY
4 - NEGATIVE CABLE
5 - POSITIVE CABLE
6 - CLIP
7 - FENDER INNER SHIELD
8 - POWER DISTRIBUTION CENTER
14 - 64 FUEL DELIVERY - DIESELDR
FUEL HEATER (Continued)

INSTALLATION
WARNING: BEFORE SERVICING THE STEERING
COLUMN THE AIRBAG SYSTEM MUST BE DIS-
ARMED. REFER TO ELECTRICAL RESTRAINT SYS-
TEM FOR SERVICE PROCEDURES. FAILURE TO DO
SO MAY RESULT IN ACCIDENTAL DEPLOYMENT OF
THE AIRBAG AND POSSIBLE PERSONAL INJURY.
CAUTION: All fasteners must be torqued to specifi-
cation to ensure proper operation of the steering
column.
(1) Position the steering column on the dash panel
support and loosely install the mounting nuts.
(2) Firmly slide the steering column upward
against the studs in dash panel and hand tighten the
nuts.
(3) Install the steering shaft coupler on the steer-
ing shaft and loosely install anewbolt.
(4) Center steering column in dash opening and
tighten mounting nuts to 28 N´m (250 in. lbs.).
NOTE: Torque the upper left nut first then the lower
right nut. Then torque the lower left nut then the
upper right nut.
NOTE: A new bolt must be used for reinstallation.
(5) Tighten the coupler bolt to 57 N´m (42 ft. lbs.).
(6) Install a new brake light switch (Refer to 8 -
ELECTRICAL/LAMPS/LIGHTING - EXTERIOR/
BRAKE LAMP SWITCH - REMOVAL).(7) Install the shifter cable. (Refer to 21 - TRANS-
MISSION/TRANSAXLE/AUTOMATIC - 32RH/GEAR
SHIFT CABLE - INSTALLATION)
(8) Connect the wiring harness to the column.
(9) Install the SKIM module.
(10) Install the clockspring(Refer to 8 - ELECTRI-
CAL/RESTRAINTS/CLOCKSPRING - REMOVAL).
(11) Install the shrouds.
(12) Install the steering column opening cover
(Refer to 23 - BODY/INSTRUMENT PANEL/STEER-
ING COLUMN OPENING COVER - INSTALLA-
TION).
(13) Align the spline on the wheel hub to shaft.
(14) Then install the steering wheel and install a
newbolt. Tighten the bolt to 61 N´m (45 ft. lbs.).
(15) Install the airbag (Refer to 8 - ELECTRICAL/
RESTRAINTS/DRIVER AIRBAG - INSTALLATION).
(16) Install the two steering wheel switches.
(17) Install the tilt lever handle.
(18) Install the negative battery terminal.
(19) Test the operation of the horn, Electronic
PRNDL Indicator, lights and any other functions that
are steering column operated.IGNITION SWITCH
DESCRIPTION
The ignition switch is located on the steering col-
umn. It is used as the main on/off switching device
for most electrical components. The mechanical key
cylinder is used to engage/disengage the electrical
ignition switch.
OPERATION
Vehicles equipped with an automatic trans-
mission and a steering column mounted shifter:
an interlock device is located within the shift cable.
This interlock device is used to lock the transmission
shifter in the PARK position when the key cylinder is
in any position and the brake pedal is not depressed.
DIAGNOSIS AND TESTING - IGNITION SWITCH
TEST AND REPAIR
If the key removal effort is excessive on a vehicle
with a automatic transmission first adjust the shift
linkage, (Refer to 21 - TRANSMISSION/TRANS-
AXLE/AUTOMATIC - 46RE/GEAR SHIFT CABLE -
ADJUSTMENTS).
If the ignition switch effort is excessive remove the
ignition key cylinder from the steering column. (Refer
to 19 - STEERING/COLUMN/LOCK CYLINDER
HOUSING - REMOVAL). Check the turning effort of
the key cylinder. If the ignition key cylinder effort is
excessive replace the key cylinder.
Fig. 7 STEERING COLUMN
1 - Steering Wheel
2 - Key Cylinder
3 - Gear Shift Lever
4 - Steering Column
5 - Tilt Lever Cable
DRCOLUMN 19 - 9
COLUMN (Continued)

(9) Fill the transmission with the recommended
fluid.
TRANSMISSION CONTROL
RELAY
DESCRIPTION
The relay is supplied fused B+ voltage, energized
by the TCM, and is used to supply power to the sole-
noid pack when the transmission is in normal oper-
ating mode.
OPERATION
When the relay is ªoffº, no power is supplied to the
solenoid pack and the transmission is in ªlimp-inº
mode. After a controller reset, the TCM energizes the
relay. Prior to this, the TCM verifies that the con-
tacts are open by checking for no voltage at the
switched battery terminals. After this is verified, the
voltage at the solenoid pack pressure switches is
checked. After the relay is energized, the TCM mon-
itors the terminals to verify that the voltage is
greater than 3 volts.
TRANSMISSION RANGE
SENSOR
DESCRIPTION
The Transmission Range Sensor (TRS) is part of
the solenoid module, which is mounted to the top of
the valve body inside the transmission.
The Transmission Range Sensor (TRS) has five
switch contact pins that:
²Determine shift lever position
²Supply ground to the Starter Relay in Park and
Neutral only.
²Supply +12 V to the backup lamps in Reverse
only.
The TRS also has an integrated temperature sen-
sor (thermistor) that communicates transmission
temperature to the TCM and PCM.
OPERATION
The Transmission Range Sensor (TRS) communi-
cates shift lever position to the TCM as a combina-
tion of open and closed switches. Each shift lever
position has an assigned combination of switch states
(open/closed) that the TCM receives from four sense
circuits. The TCM interprets this information and
determines the appropriate transmission gear posi-
tion and shift schedule.
There are many possible combinations of open and
closed switches (codes). Seven of these possible codes
are related to gear position and five are recognized
as ªbetween gearº codes. This results in many codes
which shouldnever occur. These are called
ªinvalidº codes. An invalid code will result in a DTC,
and the TCM will then determine the shift lever
position based on pressure switch data. This allows
reasonably normal transmission operation with a
TRS failure.
GEAR C5 C4 C3 C2 C1
ParkCL OP OP CL CL
Temp 1CL OP OP CL OP
ReverseOP OP OP CL OP
Temp 2OP OP CL CL OP
Neutral 1OP OP CL CL CL
Neutral 2OP CL CL CL CL
Temp 3OP CL CL CL OP
DriveOP CL CL OP OP
Temp 4OP CL OP OP OP
Manual 2CL CL OP OP OP
Temp 5CL OP OP OP OP
Manual 1CL OP CL OP OP
Fig. 125 Checking Torque Converter Seating-Typical
1 - SCALE
2 - STRAIGHTEDGE
DRAUTOMATIC TRANSMISSION - 45RFE/545RFE 21 - 581
TORQUE CONVERTER (Continued)

seconds. Refer to Electronic Control Modules for
more information on the JTEC 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 transducer switch²JTEC
(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
to 2000 rpm. This procedure (burnishing) will seat
the opposing friction surfaces and provide a higher
compressor clutch torque capability.
REMOVAL
The refrigerant system can remain fully-charged
during compressor clutch, rotor, or coil replacement.
The compressor clutch can be serviced in the vehicle.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the serpentine drive belt(Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(3) Unplug the compressor clutch coil wire harness
connector.
(4) Remove the bolts that secure the compressor to
the mounting bracket.
(5) Remove the compressor from the mounting
bracket. Support the compressor in the engine com-
partment while servicing the clutch.
(6) Insert the two pins of the spanner wrench
(Special Tool C-4489 or equivalent) into the holes of
the clutch plate. Hold the clutch plate stationary and
remove the hex nut (Fig. 2).
(7) Remove the clutch plate.
(8) Remove the compressor clutch shims.
(9) Remove the external front housing snap ring
with snap ring pliers (Fig. 3).
(10)
Install the lip of the rotor puller (Special Tool
C-6141-1 or equivalent) into the snap ring groove
exposed in the previous step, and install the shaft pro-
tector (Special Tool C-6141-2 or equivalent) (Fig. 4).
Fig. 1 COMPRESSOR CLUTCH - TYPICAL
1 - CLUTCH PLATE
2 - SHAFT KEY (not used on KJ)
3 - ROTOR
4 - COIL
5 - CLUTCH SHIMS
6 - SNAP RING
7 - SNAP RING
24 - 10 CONTROLSDR
A/C COMPRESSOR CLUTCH (Continued)

NOTE: The air gap is determined by the spacer
shims. When installing an original, or a new clutch
assembly, try the original shims first. When install-
ing a new clutch onto a compressor that previously
did not have a clutch, use a 1.0, 0.50, and 0.13 mil-
limeter (0.040, 0.020, and 0.005 inch) shims from the
new clutch hardware package that is provided with
the new clutch.
(9) To complete the procedure, (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING/A/C
COMPRESSOR - INSTALLATION).
A/C COMPRESSOR CLUTCH
RELAY
DESCRIPTION
The compressor clutch relay is a International
Standards Organization (ISO) micro-relay. The termi-
nal designations and functions are the same as a con-
ventional ISO relay. However, the micro-relay
terminal orientation (footprint) is different, the cur-
rent capacity is lower, and the relay case dimensions
are smaller than those of the conventional ISO relay.
The compressor clutch relay is located in the Power
Distribution Center (PDC) in the engine compart-
ment. Refer to the PDC label for relay identification
and location.
OPERATION
The compressor clutch relay is a electromechanical
device that switches battery current to the compres-
sor clutch coil when the Powertrain Control Module
(PCM) grounds the coil side of the relay. The PCM
responds to inputs from the A/C Heater mode control
switch, the A/C low pressure switch, and the A/C
high pressure switch. (Refer to 24 - HEATING & AIR
CONDITIONING/CONTROLS/A/C COMPRESSOR
CLUTCH RELAY - DIAGNOSIS AND TESTING)
The compressor clutch relay cannot be repaired
and, if faulty or damaged, it must be replaced.
DIAGNOSIS AND TESTING - COMPRESSOR
CLUTCH RELAY
RELAY TEST
The compressor clutch relay (Fig. 10) is located in
the Power Distribution Center (PDC). Refer to the
PDC label for relay identification and location.
Remove the relay from the PDC to perform the fol-
lowing tests:
(1) 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 2. If not OK, replace the faulty relay.(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
Fig. 10 COMPRESSOR CLUTCH RELAY
30 - COMMON FEED
85 - COIL GROUND
86 - COIL BATTERY
87 - NORMALLY OPEN
87A - NORMALLY CLOSED
DRCONTROLS 24 - 13
A/C COMPRESSOR CLUTCH (Continued)

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
The A/C heater system uses a seriers of electrical
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 A/C heater control - (Single Zone) or (Dual
Zone) panel is located to the right of the instrument
cluster on the instrument panel.
The control panel contains a rotary-type tempera-
ture control, a rotary-type mode control switch knob,
and a rotary-type blower motor speed switch knob.
The control also has a push button to activate the
Optional side view mirrors defroster elements and to
turn the A/C on.
The Dual Zone HVAC control panel contains a pair
of slider-type temperature controls, a rotary-type
mode control switch knob and a rotary-type blower
motor speed switch knob. The control also has but-
tons to turn the A/C ON, Set it on Max A/C and for
the Optional Heated Sideview Mirrors.The A/C heater control panel cannot be repaired. If
faulty or damaged, the entire unit must be replaced.
The illumination lamps are available for service
replacement.
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 the center bezel from the instrument
panel(Refer to 23 - BODY/INSTRUMENT PANEL/IN-
STRUMENT PANEL CENTER BEZEL - REMOVAL).
(3) Remove the screws that secure the A/C Heater
control to the instrument panel (Fig. 11) or (Fig. 12).
(4) Pull the A/C Heater control assembly away
from the instrument panel far enough to access the
connections on the back of the control.
(5) Unplug the wire harness connectors from the
back of the A/C Heater control (Fig. 13).
Fig. 11 Single Zone HVAC Control
1 - Mounting Tab (4)
2 - A/C Button
3 - Sideview Mirror Defroster Button (if equiped)
4 - Mode Control
5 - Blend Air Control
6 - Blower Motor Speed Control
24 - 14 CONTROLSDR
A/C COMPRESSOR CLUTCH RELAY (Continued)