2002 JEEP GRAND CHEROKEE starter switch

8W-30 FUEL/IGNITION SYSTEM
Component Page
A/C Compressor Clutch Relay . . . 8W-30-23, 35, 39, 41, 42
A/C Pressure Transducer........ 8W-30-21, 42, 45, 31
Accelerator Pedal Position Sensor........ 8W-30-37, 48
Adjustable Pedals Module................ 8W-30-33
Adjustable Pedals Motor/Sensor Assembly.... 8W-30-33
Adjustable Pedals Switch................ 8W-30-33
Auto Shut Down Relay...... 8W-30-8, 9, 12, 24, 25, 26,
27, 28, 29, 30, 35, 39, 41
Battery Temperature Sensor.......... 8W-30-2, 11, 50
Body Control Module................... 8W-30-46
Boost Pressure Sensor.................. 8W-30-45
Brake Lamp Switch.............. 8W-30-4, 5, 32, 51
Camshaft Position Sensor........ 8W-30-18, 19, 20, 49
Capacitor........................... 8W-30-12
Capacitor No. 1....................... 8W-30-16
Capacitor No. 2....................... 8W-30-17
Clockspring...................... 8W-30-4, 5, 38
Coil On Plug No. 1.................... 8W-30-17
Coil On Plug No. 2.................... 8W-30-16
Coil On Plug No. 3.................... 8W-30-17
Coil On Plug No. 4.................... 8W-30-16
Coil On Plug No. 5.................... 8W-30-17
Coil On Plug No. 6.................... 8W-30-16
Coil On Plug No. 7.................... 8W-30-17
Coil On Plug No. 8.................... 8W-30-16
Coil Rail............................ 8W-30-12
Controller Antilock Brake........... 8W-30-2, 36, 51
Crankcase Heater..................... 8W-30-35
Crankshaft Position Sensor....... 8W-30-18, 19, 20, 49
Data Link Connector............... 8W-30-6, 7, 46
Diagnostic Junction Port.......... 8W-30-6, 7, 33, 46
EGR Solenoid........................ 8W-30-50
Electronic Speed Control Servo........... 8W-30-4, 5
Engine Control Module.... 8W-30-34, 35, 36, 37, 38, 39,
40, 41, 42, 43, 44, 45,
46, 47, 48, 49, 50, 51
Engine Coolant Temperature Sensor . . . 8W-30-21, 22, 47
Engine Oil Pressure Sensor......... 8W-30-21, 22, 45
Engine Starter Motor Relay......... 8W-30-18, 19, 39
EVAP/Purge Solenoid.................. 8W-30-4, 5
Fuel Injector No. 1............... 8W-30-13, 15, 44
Fuel Injector No. 2............... 8W-30-13, 14, 44
Fuel Injector No. 3............... 8W-30-13, 15, 44
Fuel Injector No. 4............... 8W-30-13, 14, 44
Fuel Injector No. 5............... 8W-30-13, 15, 44
Fuel Injector No. 6.................. 8W-30-13, 14
Fuel Injector No. 7..................... 8W-30-15
Fuel Injector No. 8..................... 8W-30-14
Fuel Pressure Sensor................... 8W-30-37
Fuel Pressure Solenoid.................. 8W-30-47
Fuel Pump Module.................... 8W-30-10
Fuel Pump Relay.................. 8W-30-8, 9, 10
Fuel Tank Module..................... 8W-30-45
Fuse 6........................... 8W-30-8, 42
Fuse 10............................ 8W-30-33
Fuse 11............................ 8W-30-43
Fuse 12......................... 8W-30-8, 9, 40
Fuse 13............................ 8W-30-41
Fuse 16 . . 8W-30-24, 25, 26, 27, 28, 29, 30, 35, 37, 39, 41
Component Page
Fuse 19............................. 8W-30-9
Fuse 21......................... 8W-30-4, 5, 32
Fuse 22............................ 8W-30-34
Fuse 23............................ 8W-30-39
Fuse 24............................. 8W-30-9
Fuse 26..................... 8W-30-8, 12, 41, 47
Fuse 31............................ 8W-30-39
G103....................... 8W-30-8, 34, 39, 46
G104......................... 8W-30-26, 27, 30
G105........................... 8W-30-35, 39
G108........................... 8W-30-23, 43
G123.............................. 8W-30-50
G300............................ 8W-30-4, 33
G301............................ 8W-30-5, 10
Generator...................... 8W-30-3, 23, 35
Glow Plug No. 1...................... 8W-30-42
Glow Plug No. 2...................... 8W-30-43
Glow Plug No. 3...................... 8W-30-42
Glow Plug No. 4...................... 8W-30-43
Glow Plug No. 5...................... 8W-30-42
Glow Plug Relay No. 1............. 8W-30-35, 42, 43
Glow Plug Relay No. 2............. 8W-30-35, 42, 43
Hydraulic Cooling Module . . . 8W-30-3, 24, 25, 30, 31, 43
Idle Air Control Motor.................. 8W-30-20
Intake Air Temperature Sensor....... 8W-30-21, 22, 38
Intake Port Swirl Actuator............... 8W-30-39
Junction Block......... 8W-30-4, 5, 8, 9, 32, 33, 39, 40
Knock Sensor........................ 8W-30-11
Leak Detection Pump................... 8W-30-23
Manifold Absolute Pressure Sensor.... 8W-30-20, 21, 22
Mass Air Flow Sensor.................. 8W-30-37
Output Speed Sensor.................... 8W-30-2
Oxygen Sensor 1/1 Upstream...... 8W-30-25, 26, 28, 29
Oxygen Sensor 1/2 Downstream.... 8W-30-24, 25, 26, 30
Oxygen Sensor 2/1 Upstream........ 8W-30-27, 28, 29
Oxygen Sensor 2/2 Downstream...... 8W-30-24, 27, 30
Oxygen Sensor Downstream Relay . . 8W-30-24, 26, 27, 30
Park/Neutral Position Switch............. 8W-30-33
Power Distribution Center...... 8W-30-8, 9, 12, 24, 25,
26, 27, 28, 29, 30, 34, 35,
37, 39, 41, 42, 43, 47
Powertrain Control Module . . . 8W-30-2, 3, 4, 5, 6, 7, 8, 9,
10, 11, 12, 13, 14, 15, 16, 17,
18, 19, 20, 21, 22, 23, 24, 25,
26, 27, 28, 29, 30, 31, 32
Shifter Assembly............... 8W-30-2, 32, 38, 40
Speed Control Switch No. 1........... 8W-30-4, 5, 38
Speed Control Switch No. 2........... 8W-30-4, 5, 38
Throttle Position Sensor................. 8W-30-20
Transfer Case Position Sensor........... 8W-30-8, 51
Transmission Control
Module............. 8W-30-6, 7, 20, 23, 32, 36, 40
Transmission Control Relay.............. 8W-30-23
Transmission Solenoid................ 8W-30-3, 21
Transmission Solenoid/TRS Assembly....... 8W-30-33
Viscous/Cabin Heater................... 8W-30-39
Viscous/Cabin Heater Relay...... 8W-30-35, 39, 41, 42
Wastegate Solenoid.................... 8W-30-35
Water In Fuel Sensor................... 8W-30-50
WJ8W-30 FUEL/IGNITION SYSTEM 8W - 30 - 1

8W-31 TRANSMISSION CONTROL SYSTEM
Component Page
Auto Shut Down Relay................ 8W-31-4
Back-Up Lamp Relay................ 8W-31-15
Body Control Module................ 8W-31-14
Brake Lamp Switch............... 8W-31-14, 15
Controller Antilock Brake............. 8W-31-17
Crankshaft Position Sensor.......... 8W-31-9, 10
Data Link Connector............ 8W-31-9, 10, 16
Diagnostic Junction Port............ 8W-31-4, 15
Engine Control Module............ 8W-31-16, 17
Engine Starter Motor Relay..... 8W-31-4, 5, 6, 12
Fuel Pump Relay.................... 8W-31-4
Fuse 5........................... 8W-31-2, 3
Fuse 12......................... 8W-31-4, 15
Fuse 20.......................... 8W-31-5, 6
Fuse 21........................ 8W-31-14, 15
Fuse 28.......................... 8W-31-2, 8
Fuse 31............................ 8W-31-4
G102.......................... 8W-31-11, 13
G108.............................. 8W-31-3
G200.......................... 8W-31-14, 15
G300............................. 8W-31-15
G301............................. 8W-31-15Component Page
Generator.......................... 8W-31-2
Input Speed Sensor.................. 8W-31-13
Junction Block............. 8W-31-4, 5, 6, 14, 15
Left Rear Lamp Assembly............ 8W-31-5, 6
Line Pressure Sensor................ 8W-31-13
Output Speed Sensor.............. 8W-31-8, 13
Park/Neutral Position Switch........... 8W-31-6
Power Distribution Center......... 8W-31-2, 3, 8
Powertrain Control
Module......... 8W-31-2, 4, 5, 6, 7, 8, 9, 10, 14
Right Rear Lamp Assembly........... 8W-31-5, 6
Shifter Assembly.............. 8W-31-14, 15, 16
Throttle Position Sensor............... 8W-31-7
Transfer Case Position Sensor........ 8W-31-6, 16
Transmission Control
Module........... 8W-31-3, 4, 7, 9, 10, 11, 12,
13, 14, 16, 17, 18
Transmission Control Relay . . . 8W-31-2, 3, 8, 11, 12
Transmission Solenoid.............. 8W-31-2, 8
Transmission Solenoid Assembly........ 8W-31-18
Transmission Solenoid/TRS
Assembly.............. 8W-31-3, 5, 11, 12, 13
WJ8W-31 TRANSMISSION CONTROL SYSTEM 8W - 31 - 1

8W-39 VEHICLE THEFT SECURITY SYSTEM
Component Page
Automatic Headlamp Light
Sensor/VTSS LED.................. 8W-39-3
Body Control Module . . . 8W-39-2, 3, 4, 5, 7, 8, 9, 10
Clockspring....................... 8W-39-7, 8
Diagnostic Junction Port............... 8W-39-9
Driver Cylinder Lock Switch............ 8W-39-6
Driver Door Lock Motor/Ajar Switch...... 8W-39-6
Driver Door Module................ 8W-39-6, 11
Engine Starter Motor Relay............ 8W-39-2
Fuse 7........................ 8W-39-3, 9, 11
Fuse 8............................. 8W-39-2
Fuse 18.......................... 8W-39-7, 8
Fuse 22.......................... 8W-39-2, 9
Fuse 28............................ 8W-39-2
G106............................. 8W-39-10
G108............................ 8W-39-7, 8
G200.............................. 8W-39-9
G300............................ 8W-39-5, 6Component Page
G301....................... 8W-39-4, 5, 6, 11
Hood Ajar Switch................... 8W-39-10
Horn No. 1....................... 8W-39-7, 8
Horn No. 2....................... 8W-39-7, 8
Horn Relay....................... 8W-39-7, 8
Horn Switch...................... 8W-39-7, 8
Ignition Switch...................... 8W-39-2
Junction Block........ 8W-39-2, 3, 4, 5, 7, 8, 9, 11
Left Liftgate Ajar Switch.............. 8W-39-4
Left Rear Door Lock Motor/Ajar Switch . . . 8W-39-5
Liftgate Flip-Up Ajar Switch............ 8W-39-4
Passenger Door Lock Motor/Ajar Switch . . . 8W-39-6
Passenger Door Module............... 8W-39-6
Power Distribution Center......... 8W-39-2, 7, 8
Remote Keyless Module.............. 8W-39-11
Right Liftgate Ajar Switch............. 8W-39-4
Right Rear Door Lock Motor/Ajar Switch . . 8W-39-5
Sentry Key Immobilizer Module......... 8W-39-9
WJ8W-39 VEHICLE THEFT SECURITY SYSTEM 8W - 39 - 1

CONNECTOR NAME/
NUMBERCOLOR LOCATION FIG.
Trailer Tow Brake Lamp Relay BK Left Quarter Panel N/S
Trailer Tow Circuit Breaker BK Left Quarter Panel N/S
Trailer Tow Connector BK In Rear Bumper 39
Trailer Tow Left Turn Relay BK Left Quarter Panel N/S
Trailer Tow Right Turn Relay BK Left Quarter Panel N/S
Transfer Case Position Sensor BK On Transfer Case 7
Transmission Control Module
(4.7L)BK Rear of Engine Compartment 14, 15, 18
Transmission Control Module
C1 (Diesel)BK Right Rear Side of Engine
CompartmentN/S
Transmission Control Module
C2 (Diesel)BK Right Rear Side of Engine
Compartment8
Transmission Solenoid (4.0L
Gas)BK Left Side of Transmission 12
Transmission Solenoid
Assembly (Diesel)BK On Transmission 8
Transmission Solenoid/TRS
Assembly (4.7L)GY Left Side of Transmission 16
Underhood Lamp BK At Lamp 6
Vehicle Information Center BK In Overhead Console N/S
Viscous/Cabin Heater (Diesel) BK Left Rear of Engine Compartment N/S
Washer Fluid Level Switch GY Left Front of Engine Compartment 3, 4
Wastegate Solenoid (Diesel) Near Power Distribution Center N/S
Water In Fuel Sensor (Diesel) BK Left Rear of Engine Compartment N/S
GROUNDS
GROUND NUMBER LOCATION FIG.
G100 (4.0L and Diesel) Near Starter N/S
G100 (4.7L) Near Intake Plenum N/S
G101 Near Battery 2
G102 Right Side of Engine 14, 15
G103 Right Side of Engine 7, 8, 10, 11, 14, 15
G104 (4.0L) Right Rear of Engine 10, 11
G104 (4.7L) Left Side of Engine 13
G105 Right Side of Engine 8
G106 Left Side of Engine Compartment 3, 4
G107 Left Side of Engine Compartment 3, 4
G108 Near Power Distribution Center 5
G200 Near Airbag Control Module 19, 20, 21, 22
G201 Near Airbag Control Module 19, 20, 21, 22
G300 Near Right Front Seat 34, 36
G301 Near Left Front Seat 33, 35
WJ8W-91 CONNECTOR/GROUND/SPLICE LOCATION 8W - 91 - 11
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)

CONDITION POSSIBLE CAUSES CORRECTION
OIL PRESSURE DROP 1. Low oil level. 1. Check and correct oil level.
2. Faulty oil pressure sending unit. 2. Replace sending unit (Refer to 9 -
ENGINE/LUBRICATION/OIL
PRESSURE SENSOR/SWITCH -
REMOVAL).
3. Low oil pressure. 3. Check oil pump and bearing
clearance.
4. Clogged oil filter. 4. Replace oil filter (Refer to 9 -
ENGINE/LUBRICATION/OIL FILTER -
REMOVAL).
5. Worn oil pump. 5. Replace oil pump (Refer to 9 -
ENGINE/LUBRICATION/OIL PUMP -
REMOVAL).
6. Thin or diluted oil. 6. Change oil and filter.
7. Excessive bearing clearance. 7. Replace as necessary.
8. Oil pump relief valve stuck. 8. Replace oil pump (Refer to 9 -
ENGINE/LUBRICATION/OIL PUMP -
REMOVAL).
9. Oil pick up tube loose, damaged
or clogged.9. Replace as necessary.
OIL PUMPING AT RINGS;
SPARK PLUGS FOULING1. Worn or damaged rings. 1. Hone cylinder bores and replace
rings.
2. Carbon in oil ring slots. 2. Replace rings (Refer to 9 -
ENGINE/ENGINE BLOCK/PISTON
RINGS - STANDARD PROCEDURE).
3. Incorrect ring size installed. 3. Replace rings (Refer to 9 -
ENGINE/ENGINE BLOCK/PISTON
RINGS - STANDARD PROCEDURE).
4. Worn valve guides. 4. Ream guides and replace valves
(Refer to 9 - ENGINE/CYLINDER
HEAD/INTAKE/EXHAUST VALVES &
SEATS - STANDARD PROCEDURE).
5. Leaking valve guide seals. 5. Replace valve guide seals.
DIAGNOSIS AND TESTING - CYLINDER
COMPRESSION PRESSURE
The results of a cylinder compression pressure test
can be utilized to diagnose several engine malfunc-
tions.
Ensure the battery is completely charged and the
engine starter motor is in good operating condition.
Otherwise the indicated compression pressures may
not be valid for diagnosis purposes.
(1) Clean the spark plug recesses with compressed
air.
(2) Remove the spark plugs.
(3) Secure the throttle in the wide-open position.(4) Disable the fuel system (Refer to 14 - FUEL
SYSTEM/FUEL DELIVERY - DESCRIPTION).
(5) Remove the ASD relay (Refer to 8 - ELECTRI-
CAL/IGNITION CONTROL/AUTO SHUT DOWN
RELAY - REMOVAL).
(6) Insert a compression pressure gauge and rotate
the engine with the engine starter motor for three
revolutions.
(7) Record the compression pressure on the 3rd
revolution. Continue the test for the remaining cylin-
ders.
(8) (Refer to 9 - ENGINE - SPECIFICATIONS) for
the correct engine compression pressures.
9 - 68 ENGINE - 4.7LWJ
ENGINE - 4.7L (Continued)

NOTE: When installing oil pan gasket/windage tray,
start four pan bolts at each corner before tightening
oil pickup tube. This will keep pan gasket in align-
ment.
(3) Install oil pump pick-up tube using a new
O-ring. First tighten bolt at O-ring end of tube to 28
N´m (20 ft. lbs.). Tighten remain tube support fasten-
ers to 28 N´m (20 ft. lbs.).
(4) Install oil pan and tighten fasteners to 15 N´m
(11 ft. lbs.) (Fig. 95).
(5) Reconnect transmission oil cooler lines to oil
pan stud bolt.
(6) Install starter (Refer to 8 - ELECTRICAL/
STARTING/STARTER MOTOR - INSTALLATION).
(7) Install exhaust system Y-pipe.
(8) Install structural cover (Refer to 9 - ENGINE/
ENGINE BLOCK/STRUCTURAL COVER - INSTAL-
LATION).
(9) Lower vehicle.
(10) Fill engine with proper amount of oil (Refer to
LUBRICATION & MAINTENANCE/FLUID TYPES -
SPECIFICATIONS).
(11) Connect negative cable to battery.
OIL PRESSURE SENSOR/
SWITCH
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
²
A signal to the PCM relating to engine oil pressure
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 the
instrument 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.
REMOVAL
(1) Disconnect the negative cable from the battery.
(2) Raise vehicle on hoist.
(3) Remove front splash shield.
(4) Disconnect oil pressure sender wire (Fig. 96).
(5) Remove the pressure sender (Fig. 96).
INSTALLATION
(1) Install oil pressure sender.
(2) Connect oil pressure sender wire.
(3) Install front splash shield.
(4) Lower vehicle.
(5) Connect the negative battery cable.
Fig. 95 Oil Pan Tightening Sequence
Fig. 96 Oil Pressure Sending Unit
1 - BELT
2 - OIL PRESSURE SENSOR
3 - OIL FILTER
4 - ELEC. CONNECTOR
WJENGINE - 4.7L 9 - 133
OIL PAN (Continued)