2002 JEEP GRAND CHEROKEE fan motor

ENGINE CONTROL MODULE C1 (DIESEL) - BLACK 81 WAY
CAV CIRCUIT FUNCTION
55 B22 20DG/YL VEHICLE SPEED SENSOR SIGNAL
56 K225 18BK ACCELERATOR PEDAL POSITION SENSOR 2 GROUND
57 - -
58 K4 20BK/LB WATER IN FUEL SENSOR GROUND
59 K900 18GY INTAKE PORT SWIRL ACTUATOR SIGNAL
60 K7 20RD/WT FUEL PRESSURE SENSOR 5 VOLT SUPPLY
61 K51 20DB/YL AUTO SHUT DOWN RELAY CONTROL
62 - -
63 - -
64 - -
65 - -
66 - -
67 K173 20GY HYDRAULIC RADIATOR FAN SOLENOID CONTROL
68 - -
69 C13 20DB/RD A/C COMPRESSOR CLUTCH RELAY CONTROL
70 - -
71 - -
72 K236 20GY/PK GLOW PLUG RELAY NO. 2 CONTROL
73 - -
74 T752 20DG/RD ENGINE STARTER MOTOR RELAY CONTROL
75 K132 20BR/BK VISCOUS/CABIN HEATER RELAY CONTROL
76 Y42 20BR/BK WASTEGATE SOLENOID CONTROL
77 K152 20WT GLOW PLUG RELAY NO. 1 CONTROL
78 - -
79 - -
80 K46 20DB/BK FUEL PRESSURE SOLENOID CONTROL
81 K46 20DB/BK FUEL PRESSURE SOLENOID CONTROL
ENGINE CONTROL MODULE C2 (DIESEL) - BLACK 40 WAY
CAV CIRCUIT FUNCTION
82 D21 20PK SCI TRANSMIT
83 - -
84 - -
85 - -
86 - -
87 - -
88 - -
89 K35 20GY/YL EGR SOLENOID CONTROL
90 - -
91 - -
92 - -
93 - -
94 G123 20DG/WT WATER IN FUEL SENSOR SIGNAL
95 - -
96 - -
97 - -
98 - -
99 - -
100 - -
101 - -
102 - -
103 - -
104 - -
8W - 80 - 76 8W-80 CONNECTOR PIN-OUTWJ

HORN NO. 2 - BLACK 2 WAY
CAV CIRCUIT FUNCTION
1 Z307 18BK GROUND
2 X2 18DG/RD HORN RELAY OUTPUT
HYDRAULIC COOLING MODULE - BLACK 3 WAY
CAV CIRCUIT FUNCTION
1 F15 18DB/WT (DIESEL) FUSED AUTO SHUT DOWN RELAY OUTPUT
1 F142 18OR/DG (GAS) FUSED AUTO SHUT DOWN RELAY OUTPUT
2 K173 18LG (DIESEL) HYDRAULIC RADIATOR FAN RELAY CONTROL
2 K173 18LG (GAS) RADIATOR FAN RELAY CONTROL
3 Z500 18BK GROUND
IDLE AIR CONTROL MOTOR - BLACK 4 WAY
CAV CIRCUIT FUNCTION
1 K59 18VT/BK IDLE AIR CONTROL NO. 4 DRIVER
2 K40 18BR/WT IDLE AIR CONTROL NO. 3 DRIVER
3 K60 18YL/BK IDLE AIR CONTROL NO. 2 DRIVER
4 K39 18GY/BK IDLE AIR CONTROL NO. 1 DRIVER
IGNITION SWITCH C1 - WHITE 6 WAY
CAV CIRCUIT FUNCTION
1 A41 12YL IGNITION SWITCH OUTPUT (START)
2 A2 12PK/BK FUSED B(+)
3 A22 12BK/OR IGNITION SWITCH OUTPUT (RUN)
4 A1 12RD FUSED B(+)
5 A31 12RD/BK IGNITION SWITCH OUTPUT (RUN-ACC)
6 A21 12DB IGNITION SWITCH OUTPUT (RUN-START)
IGNITION SWITCH C2 - BLACK 2 WAY
CAV CIRCUIT FUNCTION
1 G26 20LB KEY-IN IGNITION SWITCH SENSE
2 Z234 20BK GROUND
8W - 80 - 84 8W-80 CONNECTOR PIN-OUTWJ

POWERTRAIN CONTROL MODULE C3 (GAS) - GRAY 32 WAY
CAV CIRCUIT FUNCTION
1 C13 18DB/OR A/C COMPRESSOR CLUTCH RELAY CONTROL
2- -
3 K51 18DB/YL AUTO SHUT DOWN RELAY CONTROL
4 V36 18TN/RD SPEED CONTROL VACUUM SOLENOID CONTROL
5 V35 18LG/RD SPEED CONTROL VENT SOLENOID CONTROL
6- -
7 K42 18DB/LG (4.7L HIGH OUTPUT) KNOCK SENSOR NO. 1 SIGNAL
8 K99 18BR/OR OXYGEN SENSOR 1/1 HEATER CONTROL
9 K512 18RD/YL (EXCEPT 4.0L
BUILT-UP-EXPORT)OXYGEN SENSOR DOWNSTREAM RELAY CONTROL
10 K106 18WT/DG (EXCEPT
BUILT-UP-EXPORT)LEAK DETECTION PUMP SOLENOID CONTROL
11 V32 18OR/DG SPEED CONTROL SUPPLY
12 F42 18DG/LG FUSED AUTO SHUT DOWN RELAY OUTPUT
13 T10 18YL/DG (4.7L RHD) TORQUE MANAGEMENT REQUEST SENSE
13 T6 18OR/WT (4.0L LHD) OVERDRIVE OFF SWITCH SENSE
13 T10 18DG/LG (4.7L LHD) TORQUE MANAGEMENT REQUEST SENSE
13 T6 18OR/BK (4.0L RHD) OVERDRIVE OFF SWITCH SENSE
14 K107 18OR/PK (EXCEPT
BUILT-UP-EXPORT)LEAK DETECTION PUMP SWITCH SENSE
15 K25 18VT/LG BATTERY TEMPERATURE SENSOR SIGNAL
16 K299 18BR/WT OXYGEN SENSOR 1/2 HEATER CONTROL
17 - -
18 K142 18GY/BK (4.7L HIGH OUTPUT) KNOCK SENSOR NO. 2 SIGNAL
19 K31 18BR FUEL PUMP RELAY CONTROL
20 K52 18PK/BK DUTY CYCLE EVAP/PURGE SOLENOID CONTROL
21 - -
22 - -
23 - -
24 K29 18WT/PK SECONDARY BRAKE SWITCH SIGNAL
25 K125 18WT/DB GENERATOR SOURCE
26 K226 18LB/YL FUEL LEVEL SENSOR SIGNAL
27 D21 18PK SCI TRANSMIT
28 - -
29 D32 18LG (LHD) SCI RECEIVE
29 D32 18LG/DG (RHD) SCI RECEIVE
30 D25 18VT/YL PCI BUS
31 - -
32 V37 18RD/LG SPEED CONTROL SWITCH SIGNAL
RADIATOR FAN MOTOR - BLACK 2 WAY
CAV CIRCUIT FUNCTION
1 C23 12DG RADIATOR FAN RELAY OUTPUT
2 Z4 12BK/PK GROUND
8W - 80 - 110 8W-80 CONNECTOR PIN-OUTWJ

CONNECTOR NAME/
NUMBERCOLOR LOCATION FIG.
Passenger Power Seat Rear
Riser MotorRD At Passenger Seat N/S
Passenger Power Seat
Recliner Motor (Midline/
Premium)BK At Passenger Seat N/S
Passenger Power Seat Switch
(Midline/Premium)GN At Passenger Seat N/S
Passenger Rear Power
Window MotorBK In Right Rear Door 29
Passenger Rear Power
Window SwitchBL In Right Rear Door 29
Passenger Seat Belt Switch t Switch N/S
Power Amplifier - C1 WT Under Rear Seat 34, 36
Power Amplifier - C2 WT Under Rear Seat 34, 36
Power Connector WT Center of Instrument Panel 21, 22
Powertrain Control Module -
C1 (Gas)BK Rear of Engine Compartment 5, 10, 11, 14, 15, 18
Powertrain Control Module -
C2 (Gas)WT Rear of Engine Compartment 5, 10, 11, 14, 15, 18
Powertrain Control Module -
C3 (Gas)WT Rear of Engine Compartment N/S
Radiator Fan Motor BK At Radiator 5
Radiator Fan Relay BK Right Side of Engine Compartment 5
Radio - C1 GY Center of Instrument Panel 19, 20
Radio - C2 BK Center of Instrument Panel 19, 20
Rain Sensor BK Front Center Overhead N/S
Rear Power Outlet RD Right Rear Quarter Panel 37
Rear Washer Pump BK Left Front of Engine Compartment 3, 4
Rear Window Defogger BK Right Upper Coner of Liftgate 38
Rear Wiper Motor BK In Liftgate 38
Recirculation Door Motor/
Actuator (AZC)BK Center of Instrument Panel N/S
Red Brake Warning Indicator
SwitchGY At Master Cylinder 4
Remote Keyless Module
(Japan)BL In Driver Door 25
Right Courtesy Lamp BK At Lamp 20 21, 22
Right Curtain Airbag BK Near Right C Pillar 37
Right Door Handle Courtesy
LampBK At Lamp N/S
Right Fog Lamp BK At Right Front Fascia 5
Right Front Door Speaker WT In Right Front Door 25, 26
Right Front Impact Sensor BK Near Right Verticle Radiator Support N/S
Right Front Park Lamp WT At Lamp N/S
WJ8W-91 CONNECTOR/GROUND/SPLICE LOCATION 8W - 91 - 9
CONNECTOR/GROUND/SPLICE LOCATION (Continued)

(7) Remove the fan assembly from the water pump
(Refer to 7 - COOLING/ENGINE/RADIATOR FAN -
REMOVAL).
(8) Remove the fan shroud.
(9) Disconnect the transmission fluid cooler lines
(automatic transmission).
(10) Discharge the A/C system (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE).
(11) Remove the service valves and cap the com-
pressor ports.
(12) Remove the radiator or radiator/condenser (if
equipped with A/C).
(13) Disconnect the heater hoses at the engine
thermostat housing and water pump.
(14) Disconnect the accelerator cable, transmission
line pressure cable and speed control cable (if
equipped) from the throttle body.
(15) Remove cables from the bracket and secure
out of the way.
(16) Disconnect the body ground at the engine.
(17) Disconnect the following connectors and
secure their harness out of the way.
²Power steering pressure switch
²Coolant temperature sensor
²Six (6) fuel injector connectors
²Intake air temperature sensor
²Throttle position sensor
²Map sensor
²Crankshaft position sensor
²Oxygen sensor
²Camshaft position sensor
²Generator connector and B+ terminal wire
(18) Disconnect the coil rail electrical connections
and the oil pressure switch connector.
(19) Perform the fuel pressure release procedure
(Refer to 14 - FUEL SYSTEM/FUEL DELIVERY -
STANDARD PROCEDURE).
(20) Disconnect the fuel supply line at the injector
rail (Refer to 14 - FUEL SYSTEM/FUEL DELIVERY/
QUICK CONNECT FITTING - STANDARD PROCE-
DURE).
(21) Remove the fuel line bracket from the intake
manifold.
(22) Remove the air cleaner assembly (Fig. 5).
(23) Disconnect the hoses from the fittings at the
steering gear.
(24) Drain the pump reservoir.
(25) Cap the fittings on the hoses and steering
gear to prevent foreign objects from entering the sys-
tem.
(26) Raise and support the vehicle.
(27) Disconnect the wires from the engine starter
motor solenoid.(28) Remove the engine starter motor (Refer to 8 -
ELECTRICAL/STARTING/STARTER MOTOR -
REMOVAL).
(29) Disconnect the oxygen sensor from the
exhaust pipe.
(30) Disconnect the exhaust pipe from the mani-
fold.
(31) Remove the exhaust pipe support.
(32) Remove the bending brace (Refer to 9 -
ENGINE/ENGINE BLOCK/STRUCT SUPPORT -
REMOVAL).
(33) Remove the engine flywheel/converter housing
access cover.
(34) Mark the converter and drive plate location.
(35) Remove the converter-to-drive plate bolts.
(36) Remove the upper engine flywheel/converter
housing bolts and loosen the bottom bolts.
(37) Remove the engine mount cushion-to-engine
compartment bracket bolts.
(38) Lower the vehicle.
(39) Attach a lifting device to the engine.
(40) Raise the engine off the front supports.
(41) Place a support or floor jack under the con-
verter (or engine flywheel) housing.
(42) Remove the remaining converter (or engine
flywheel) housing bolts.
(43) Lift the engine out of the engine compart-
ment.
Fig. 5 Air Cleaner Assembly
1 - POWER STEERING PUMP
2 - AIR CLEANER ASSEMBLY
9 - 12 ENGINE - 4.0LWJ
ENGINE - 4.0L (Continued)

INSTALLATION
CAUTION: When installing the engine into a vehicle
equipped with an automatic transmission, be care-
ful not to damage the trigger wheel on the engine
flywheel.
(1) Attach a lifting device to the engine and lower
the engine into the engine compartment. For easier
installation, it may be necessary to remove the
engine mount bracket as an aid in alignment of the
engine to the transmission.
(2) Align the transmission torque converter hous-
ing with the engine.
(3) Loosely install the converter housing lower
bolts and install the next higher bolt and nut on each
side.
(4) Tighten all 4 bolts finger tight.
(5) Install the engine mount brackets (if removed).
(6) Lower the engine and engine mount brackets
onto the engine compartment cushions. Install the
bolts and finger tighten the nuts.
(7) Remove the engine lifting device.
(8) Raise and support the vehicle.
(9) Install the remaining engine flywheel/converter
housing bolts. Tighten all bolts to 38 N´m (28 ft. lbs.)
torque.
(10) Install the converter-to-drive plate bolts.
(11) Ensure the installation reference marks are
aligned.
(12) Install the engine flywheel/converter housing
access cover.
(13) Install the exhaust pipe support and tighten
the screw.
(14) Install the engine bending brace (Refer to 9 -
ENGINE/ENGINE BLOCK/STRUCT SUPPORT -
INSTALLATION).
(15) Tighten the engine mount-to-bracket bolts.
(16) Connect the vehicle speed sensor wire connec-
tions and tighten the screws.
(17) Connect the exhaust pipe to the manifold.
(18) Install the engine starter motor (Refer to 8 -
ELECTRICAL/STARTING/STARTER MOTOR -
INSTALLATION).
(19) Connect the wires to the engine starter motor
solenoid.
(20) Lower the vehicle.
(21) Connect all the vacuum hoses and wire con-
nectors identified during engine removal.
(22) Remove protective caps from the power steer-
ing hoses.
(23) Connect the hoses to the fittings at the steer-
ing gear. Tighten the nut to 52 N´m (38 ft. lbs.)
torque.
(24) Fill the pump reservoir with fluid.(25) Inspect the fuel supply line o-ring(s) and
replace if necessary. Connect fuel supply line to injec-
tior rail and verify connection by pulling outward on
the line.
(26) Install the fuel line bracket to the intake
manifold.
(27) Connect the coil rail electrical connectors and
oil pressure switch connector.
(28) Connect the following electrical connectors:
²Power steering pressure switch
²Coolant temperature sensor
²Six (6) fuel injector connectors
²Intake air temperature sensor
²Throttle position sensor
²Map sensor
²Crankshaft position sensor
²Oxygen sensor
²Camshaft position sensor
²Generator connector and B+ terminal wire
(29) Connect all previously removed vacuum hoses.
(30) Connect the body ground strap.
(31) Install the throttle, transmission line pres-
sure, and speed control cables to their mounting
bracket and connect them to the throttle body.
(32) Connect the heater hoses at the engine ther-
mostat housing and water pump.
(33) Install the fan assembly (Refer to 7 - COOL-
ING/ENGINE/RADIATOR FAN - INSTALLATION).
(34) Place the fan shroud in position over the fan.
(35) Install the radiator (Refer to 7 - COOLING/
ENGINE/RADIATOR - INSTALLATION).
(36) Connect the service valves to the A/C com-
pressor ports, if equipped with A/C.
(37) Charge the air conditioner system (Refer to 24
- HEATING & AIR CONDITIONING/PLUMBING -
STANDARD PROCEDURE).
(38) Connect the radiator hoses and automatic
transmission fluid cooler pipes, if equipped.
(39) Install the fan shroud to the radiator or radi-
ator/condenser (if equipped with A/C).
(40) Install upper radiator support.
(41) Connect the upper radiator hose and tighten
the clamp.
(42) Connect the lower radiator hose and tighten
the clamp.
(43) Fill crankcase with engine oil. (Refer to
LUBRICATION & MAINTENANCE/FLUID CAPACI-
TIES - SPECIFICATIONS) for correct capacities.
(44) Fill the cooling system with reusable coolant
or new coolant (Refer to 7 - COOLING - STANDARD
PROCEDURE).
(45) Align the hood to the scribe marks. Install the
hood.
(46) Install the air cleaner assembly.
(47) Install the battery and connect the battery
cable.
WJENGINE - 4.0L 9 - 13
ENGINE - 4.0L (Continued)

(9) Lower the engine until it is properly located on
the engine mounts.
(10) Install the through bolts and tighten the nuts.
(11) Lower the jack stand and remove the piece of
wood.
(12) Install the engine flywheel and transmission
torque converter housing access cover.
(13) Install the engine starter motor. (Refer to 8 -
ELECTRICAL/STARTING/STARTER MOTOR -
INSTALLATION).
(14) Connect the exhaust pipe to the hanger and to
the engine exhaust manifold.
(15) Install transmission oil cooling lines (if
equipped) and oxygen sensor wiring supports that
attach to the oil pan studs.
(16) Install the oil pan drain plug (Fig. 81).
Tighten the plug to 34 N´m (25 ft. lbs.) torque.
(17) Lower the vehicle.
(18) Connect negative cable to battery.
(19) Fill the oil pan with engine oil to the specified
level.
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING. DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR
HANDS NEAR THE PULLEYS, BELTS OR FAN. DO
NOT WEAR LOOSE CLOTHING.
(20) Start the engine and inspect for leaks.
ENGINE OIL PRESSURE
SENSOR
DESCRIPTION
The 3±wire, solid-state engine oil pressure sensor
(sending unit) is located in an engine oil pressure
gallery.
OPERATION
The oil pressure sensor uses three circuits. They
are:
²A 5±volt power supply from the Powertrain Con-
trol Module (PCM)
²A sensor ground through the PCM's sensor
return
²A signal to the PCM relating to engine oil pres-
sure
The oil pressure sensor has a 3±wire electrical
function very much like the Manifold Absolute Pres-
sure (MAP) sensor. Meaning different pressures
relate to different output voltages.
A 5±volt supply is sent to the sensor from the PCM
to power up the sensor. The sensor returns a voltage
signal back to the PCM relating to engine oil pres-
sure. This signal is then transferred (bussed) to theinstrument panel on either a CCD or PCI bus circuit
(depending on vehicle line) to operate the oil pressure
gauge and the check gauges lamp. Ground for the
sensor is provided by the PCM through a low-noise
sensor return.
OIL PUMP
REMOVAL
A gear-type oil pump is mounted at the underside
of the cylinder block opposite the No.4 main bearing.
(1) Drain the engine oil.
(2) Remove the oil pan (Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - REMOVAL).
(3) Remove the pump-to-cylinder block attaching
bolts. Remove the pump assembly with gasket (Fig.
82).
CAUTION: If the oil pump is not to be serviced, DO
NOT disturb position of oil inlet tube and strainer
assembly in pump body. If the tube is moved within
the pump body, a replacement tube and strainer
assembly must be installed to assure an airtight
seal.
Fig. 82 Oil Pump Assembly
1 - OIL FILTER ADAPTOR
2 - BLOCK
3 - GASKET
4 - OIL INLET TUBE
5 - OIL PUMP
6 - STRAINER ASSEMBLY
7 - ATTACHING BOLTS
9 - 56 ENGINE - 4.0LWJ
OIL PAN (Continued)

INSTALLATION
A gear-type oil pump is mounted at the underside
of the cylinder block opposite the No.4 main bearing.
(1) Install the oil pump on the cylinder block using
a replacement gasket. Tighten the bolts to 23 N´m
(17 ft. lbs.) torque.
(2) Install the oil pan (Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - INSTALLATION).
(3) Fill the oil pan with oil to the specified level.
INTAKE MANIFOLD
DESCRIPTION
The intake manifold (Fig. 83) is made of cast alu-
minum and uses eleven bolts to mount to the cylin-
der head. This mounting style improves sealing and
reduces the chance of leaks.
DIAGNOSIS AND TESTING - INTAKE
MANIFOLD LEAKAGE
An intake manifold air leak is characterized by
lower than normal manifold vacuum. Also, one or
more cylinders may not be functioning.
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING. DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR
HANDS NEAR THE PULLEYS, BELTS OR THE FAN.
DO NOT WEAR LOOSE CLOTHING.
(1) Start the engine.
(2) Spray a small stream of water at the suspected
leak area.
(3) If a change in RPM is observed the area of the
suspected leak has been found.
(4) Repair as required.
REMOVAL
NOTE: THE ENGINE INTAKE AND EXHAUST MANI-
FOLD MUST BE REMOVED AND INSTALLED
TOGETHER. THE MANIFOLDS USE A COMMON
GASKET AT THE CYLINDER HEAD.
(1) Disconnect the battery negative cable.
(2) Remove air cleaner inlet hose from the resona-
tor assembly.
(3) Remove the air cleaner assembly.
(4) Remove the throttle cable, vehicle speed control
cable (if equipped) and the transmission line pres-
sure cable (Refer to 21 - TRANSMISSION/TRANS-
AXLE/AUTOMATIC - AW4/THROTTLE VALVE
CABLE - REMOVAL).
(5) Disconnect the following electrical connections
and secure their harness out of the way:
²Throttle Position Sensor
²Idle Air Control Motor
²Coolant Temperature Sensor (at thermostat
housing)
²Intake Air Temperature Sensor
²Oxygen Sensor
²Crank Position Sensor
²Six (6) Fuel Injector Connectors
²Manifold Absolute Pressure (MAP) Sensor.
(6) Disconnect HVAC, and Brake Booster vacuum
supply hoses at the intake manifold.
(7) Perform the fuel pressure release procedure.
(Refer to 14 - FUEL SYSTEM/FUEL DELIVERY -
STANDARD PROCEDURE).
(8) Disconnect and remove the fuel system supply
line from the fuel rail assembly.
(9) Remove the accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(10) Remove the power steering pump from the
intake manifold and set aside.
(11) Raise the vehicle.
(12) Disconnect the exhaust pipes from the engine
exhaust manifolds.
(13) Lower the vehicle.
(14) Remove the intake manifold and exhaust
manifold bolts and manifolds (Fig. 84).
INSTALLATION
If the manifold is being replaced, ensure all the fit-
ting, etc. are transferred to the replacement mani-
fold.
(1) Install a new engine exhaust/intake manifold
gasket over the alignment dowels on the cylinder
head.
(2) Position the engine exhaust manifolds to the
cylinder head. Install fastener Number 3 and finger
tighten at this time (Fig. 84).
Fig. 83 Intake Manifold 4.0L Engine
WJENGINE - 4.0L 9 - 57
OIL PUMP (Continued)