1995 JEEP YJ power steering

Circuit T17 from fuse 3 in the power distribution
center supplies voltage to the coil and contact sides
of the TCC relay. When the PCM provides a ground
path on circuit K54 for the coil side of the relay, the
relay contacts close.
When the relay contacts close, they connect circuit
T17 with circuit T22. Circuit T22 supplies battery
voltage to the case grounded TCC solenoid. Circuit
K54 connects to PCM cavity 54.
HELPFUL INFORMATION
²In the RUN or START position, the ignition switch
connects circuit A1 from fuse 4 in the PDC to circuit
A21.
UPSHIFT LAMP
On vehicles equipped with a manual transmission,
the PCM grounds the up-shift lamp on circuit K54.
Circuit K54 connects to cavity 54 of the PCM.
POWER STEERING PRESSURE SWITCH
The PCM supplies voltage to the power steering
pressure switch on circuit K10. Circuit Z12 provides
ground for the switch. When the switch closes, volt-
age flows through the switch to ground on circuit
Z12. The switch closes during periods of high power
steering pump load and low engine speed; such as
parking maneuvers.
Circuit K10 connects to cavity 10 of the PCM. Cir-
cuit Z12 terminates at the right rear of the engine.
TACHOMETER SIGNAL
The PCM supplies the signal for the tachometer on
circuit G21. Circuit G21 connects to cavity 43 of the
PCM.
MALFUNCTION INDICATOR LAMP (MIL)
The PCM provides ground for the instrument clus-
ter malfunction indicator lamp on circuit G3. The
MIL displays the message CHECK ENGINE when il-
luminated. Circuit F87 provides voltage for the lamp.
DATA LINK CONNECTOR
Circuit F12 supplies battery voltage to the data
link connector. Circuit F12 originates at fuse 11 in
the Power Distribution Center.
Circuit D20 connects to cavity 45 of the PCM. Cir-
cuit D20 is the SCI receive circuit for the PCM.
Circuit D21 connects to cavity 25 of the PCM. Cir-
cuit D21 is the SCI transmit circuit for the PCM.
Circuit Z11 provides ground for the data link con-
nector. Circuit Z11 terminates at the right rear of the
engine. Circuit Z11 also connects to cavity 5 of the
PCM.
HELPFUL INFORMATION
²Circuit Z1 also supplies a ground for the PCM
high current drivers.
²If the system loses ground for the Z11 circuits at
the right rear of the engine, the vehicle will not op-
erate. Check the connection at the ganged-ground cir-
cuit eyelet.
²Circuit F12 splices to supply battery voltage to the
vehicle speed control switch, back-up lamp switch,
A/C compressor clutch relay, windshield washer fluid
level sensor and radiator fan relay (4.0L engines).
BRAKE SWITCH INPUT
Circuit K29 provides the brake switch input to the
PCM. Circuit V40 connects to cavity 29 of the PCM.
POWER (DEVICE) GROUND
Circuit Z12 connects to cavities 11 and 12 of the
PCM. The Z12 circuit provides ground for PCM inter-
nal drivers that operate high current devices like the
injectors and ignition coil.
Internal to the PCM, the power (device) ground cir-
cuit connects to the PCM sensor return circuit (from
circuit K4).
HELPFUL INFORMATION
²The grounding point for circuit Z12 is the right
rear of the engine.
²If the system loses ground for the Z12 circuits at
the rear of the engine, the vehicle will not operate.
Check the connection at the ganged-ground circuit
eyelet.
²On vehicles equipped with the 4.0L engine and au-
tomatic transmission, circuit Z12 splices to provide
ground for the transmission control module.
EXTENDED IDLE SWITCH
On Police Package vehicles, an optional extended
idle switch provides an input to the Powertrain Con-
trol Module (PCM) on circuit K10. Circuit K10 con-
nects to cavity 10 of the PCM. Circuit F60 supplies
battery voltage to the extended idle switch. Circuit
Z1 grounds the switch.
CCD BUS
On vehicles equipped with the 4.0L engine, circuits
D1 and D2 connect the Powertrain Control Module
(PCM) to the CCD Bus. Circuit D1 connects to cavity
26 of the PCM. Circuit D2 connects to cavity 46 of
the PCM. Circuits D1 and D2 are a twisted pair of
wires.
J8W-30 FUEL/IGNITIONÐXJ VEHICLES 8W - 30 - 5

DIAGRAM INDEXÐ2.5L ENGINE
Component Page
Automatic Shut Down Relay.................8W-30-8
Camshaft Position Sensor..................8W-30-10
Crankshaft Position Sensor.................8W-30-11
Data Link Connector......................8W-30-12
Distributor Ignition Coil....................8W-30-12
Engine Coolant Temperature Sensor............8W-30-11
Fuel Injector #1.........................8W-30-9
Fuel Injector #2.........................8W-30-9
Fuel Injector #3.........................8W-30-9
Fuel Injector #4.........................8W-30-9
Fuel Pump Relay........................8W-30-20
Fuel Tank Gauge Level Sending Unit...........8W-30-20
Fuse 2 (PDC)........................8W-30-8, 20
Fuse 6 (PDC)........................8W-30-8, 20
Fuse 11 (PDC).........................8W-30-12
Fuse 14 (PDC)..........................8W-30-8
Heated Oxygen Sensor.....................8W-30-7
Idle Air Control Motor.....................8W-30-7
Ignition Switch.......................8W-30-8, 20
Instrument Cluster....................8W-30-12, 20
Intake Air Temperature Sensor...............8W-30-11
MAP Sensor...........................8W-30-10
Powertrain Control Module........8W-30-7 thru 12, 19, 20
Power Steering Pressure Switch...............8W-30-7
Throttle Position Sensor...................8W-30-10
Vehicle Speed Sensor.....................8W-30-12
DIAGRAM INDEXÐ4.0L ENGINE
Component Page
Automatic Shut Down Relay.................8W-30-14
Camshaft Position Sensor..................8W-30-16
Crankshaft Position Sensor.................8W-30-16
Data Link Connector......................8W-30-18
Distributor Ignition Coil....................8W-30-18
Engine Coolant Temperature Sensor............8W-30-17
Extended Idle Switch.....................8W-30-19
Extended Idle Switch Lamp.................8W-30-19
Fuel Injector #1.........................8W-30-15
Fuel Injector #2.........................8W-30-15
Fuel Injector #3.........................8W-30-15
Fuel Injector #4.........................8W-30-15
Fuel Injector #5.........................8W-30-15
Fuel Injector #6.........................8W-30-15
Fuel Pump Relay........................8W-30-20
Fuel Tank Gauge Level Sending Unit...........8W-30-20
Fuse 2 (PDC).......................8W-30-14, 20
Fuse 3 (Fuse Block)......................8W-30-19
Fuse 5 (PDC)..........................8W-30-19
Fuse 6 (PDC).....................8W-30-14, 19, 20
Fuse 14 (PDC).........................8W-30-14
Fuse 15 (Fuse Block).....................8W-30-19
Fuse 19 (Fuse Block).....................8W-30-19
Headlamp Switch........................8W-30-19
Heated Oxygen Sensor....................8W-30-13
Idle Air Control Motor.....................8W-30-13
Ignition Switch....................8W-30-14, 19, 20
Instrument Cluster.......................8W-30-18
Intake Air Temperature Sensor...............8W-30-17
MAP Sensor...........................8W-30-16
Powertrain Control Module............8W-30-13 thru 20
Throttle Position Sensor...................8W-30-16
Vehicle Speed Sensor.....................8W-30-18
8W - 30 - 6 8W-30 FUEL/IGNITIONÐXJ VEHICLESJ

HORN/CIGAR LIGHTER
HORN
The horn system uses two switches and horn relay.
The horn switches are on the steering wheel.
Circuit A7 from fuse 3 in the Power Distribution
Center (PDC) feeds a fuse block bus bar that powers
circuit X4 through fuse 11. Circuit X4 is HOT at all
times and powers the coil and contact sides of the
horn relay.
When the case grounded horn switch is depressed,
circuit X3 provides ground for the coil side of the re-
lay and the contacts close. When the contacts close,
circuit X2 supplies voltage to the case grounded
horns.
HELPFUL INFORMATION
²The horn switches are grounded to the steering
wheel.
²Circuit X4 is double crimped at the coil side of the
horn relay.
²Check fuse 3 in the PDC and fuse 11 in the fuse
block.
CIGAR LIGHTER
In the ACCESSORY or RUN position, the ignition
switch supplies voltage to fuse 2 in the fuse block on
circuit A48. Fuse 2 feeds circuit F85 which connects
to the cigar lighter. When the lighter is depressed,
the contacts inside of the lighter element close and
voltage flows to ground on circuit Z1.
HELPFUL INFORMATION
²In the ACCESSORY or RUN position, the ignition
switch connects circuit A1 from fuse 6 in the PDC
with circuit A48.
²Circuit F85 also powers the radio and LCD relay.
DIAGRAM INDEX
Component Page
Cigar Lighter...........................8W-41-3
Fuse 3 (PDC)...........................8W-41-2
Fuse 6 (PDC)...........................8W-41-3
Fuse 11 (Fuse Block)......................8W-41-2
Fuse 2 (Fuse Block).......................8W-41-3
Horns................................8W-41-2
Horn Relay.............................8W-41-2
Horn Switch............................8W-41-2
Ignition Switch..........................8W-41-3
J8W-41 HORN/CIGAR LIGHTERÐXJ VEHICLES 8W - 41 - 1

CONNECTOR LOCATIONS
GENERAL INFORMATION
This section provides illustrations identifying com-
ponent and connector locations in the vehicle. A con-nector index is provided. Use the wiring diagrams in
each section for connector number identification. Re-
fer to the index for the proper figure number.
CONNECTOR LOCATIONS
Connector # Color Location Fig.
C101......BK ...Front of Left Fender Side Shield . . .1, 2
C102......BK ...Bottom Right of Radiator Closure
Panel....................8
C103......BK ...Near Left Side of Radiator......2,8
C104......BK ...Left Fender Side Shield
C105......BK ...Bottom of Left Fender Side Shield . . .2
C106......BK ...Left Fender Side Shield, Near PCM .1, 2
C107......BK ...OnABSPump Motor...........2
C108......BK ...Right Rear Corner of Engine
Compartment.............2,3
C109......BK ...Center of Dash Panel.........1,4
C110......BK ...Center of I.P., Below ABS Control
Module...............13, 14
C111......BK ...Left of Steering Column.........14
C112......BK ...AtABSControl Module.........13
C113......BK ...InHarness, Near ABS Control
Module.................13
C114......BK ...Center of I.P., Below ABS Control
Module.................14
C115......BK ...Near ABS Control Module.......14
C116......BK ...Below ABS Control Module.......14
C117......BK ...Rear of Intake Manifold........6,7
C118......BK ...OnThrottle Body............6,7
C119......BK ...Bottom Left Front of Cylinder
Block..................6,7
C120......BK ...OnThrottle Body............6,7
C121......GY ...Rear of Intake Manifold........6,7
C122......BK ...AtThermostat Housing........6,7
C123......BK ...Injector No. 1..............6,7
C124......BK ...Injector No. 2..............6,7
C125......BK ...Injector No. 3..............6,7
C126......BK ...Injector No. 4..............6,7
C127......BK ...Injector No. 5................7
C128......BK ...Injector No. 6................7
C129......GN ...Center of Dash Panel.........1,4
C130......BK ...Below Brake Master Cylinder.....1,2
C131......BK ...Distributor................6,7
C132......GN ...Lower Right Side of I.P.
C133......BK ...Right of Blower Motor..........4
C134......GY ...Right of Blower Motor..........4
C135......GY ...Right of Blower Motor..........4
C136......BR ...OnWasher Fluid Reservoir......1,4
C137......BK ...Under Side of Hood..........1,4
C138......BK ...Left of Blower Motor...........4
C139......BK ...Bottom of Washer Fluid Reservoir .3, 4
C140......BK ...Bottom of Washer Fluid Reservoir .3, 4
C141......BK ...InFront of Washer Fluid Reservoir .1, 4
C142......BK ...Between PDC and Blower Motor . .1, 4Connector # Color Location Fig.
C143......BK ...Bottom Front of Right Fender
Side Shield..............1,3
C144......BK ...Front of Right Fender Side Shield . .1, 3
C145......BK ...Front of Right Fender Side Shield . .1, 3
C146......BK ...Right Side of Grille Opening.....1,3
C147......BK ...Below Distributor..............7
C148......BK ...Right Side of Engine..........6,7
C149......BK ...Rear of Generator...........5,6
C150......BK ...Right Rear of Engine...........7
C151......BK ...Right Fender Side Shield.......1,4
C152......GY ...Behind Power Steering Pump......6
C153......BK ...Right Side of Transmission.......21
C154......BK ...Left Side of Radiator Closure Panel . .8
C155......BK ...Left Rear of Radiator Closure Panel . .8
C156......BK ...Behind Lens.................8
C157......BK ...Behind Left Headlamp...........8
C158......BK ...Behind Lens.................8
C159......BK ...Center of Grille Opening.........8
C160......BK ...Behind Lens.................8
C161......BK ...Behind Right Headlamp..........8
C162......BK ...Behind Lens.................8
C163......BK ...Center of Grille Opening.........8
C164......BK ...Right Center of Engine Compartment
C201......BK ...Below Left Side of I.P.........9,14
C202......LG ...Behind Left Kick Panel.........14
C203......BK ...Behind Left Kick Panel.........14
C204......GY ...Behind Left Kick Panel.........14
C205......BK ...Bottom Right of I.P............12
C206......BK ...Bottom Right of I.P............12
C207......BK ...Behind Headlamp Switch........10
C208......BK ...Bottom Right of I.P............12
C209......BK ...OnI.P.Right of Steering Column . . .10
C210......BK ...OnI.P.Right of Steering Column . . .10
C211......BK ...Rear of Radio...............11
C212......BR ...Center of I.P.................10
C213......BK ...Center of I.P.................10
C214......GY ...Right Side of I.P..............13
C215......BK ...Right Side of I.P..............13
C216......GY ...Glove Box.................10
C217......BK ...Bottom Right of I.P............11
C218......RD ...Right Side of I.P...........13, 17
C219......BK ...Bottom Right of I.P............11
C220......BK ...Right Side of I.P..............13
C221......BK ...Right Corner of I.P............13
C222......LG ...Right Corner of I.P............13
C223......BK ...Right Front of Steering Column....14
C224......BK ...Right Front of Steering Column....14
C225......NAT...Below Steering Column.........14
J8W-90 CONNECTOR LOCATIONSÐXJ VEHICLES 8W - 90 - 1

HORN/CIGAR LIGHTER
HORN
The horn system uses two switches and horn relay.
The horn switches are on the steering wheel.
Circuit A7 from fuse 3 in the power distribution
center (PDC) feeds a fuse block bus bar that powers
circuit X4 through fuse 5 in the fuse block. Circuit
X4 is HOT at all times and powers the coil and con-
tact sides of the horn relay.
When the case grounded horn switch is depressed,
circuit X3 provides ground for the coil side of the re-
lay and the contacts close. When the contacts close,
circuit X2 supplies voltage to the case grounded
horns.
HELPFUL INFORMATION
²The horn switches are grounded to the steering
wheel.
²Circuit X4 is double crimped at the coil side of the
horn relay.
²Check fuse 3 in the PDC and fuse 5 in the fuse
block.
CIGAR LIGHTER
In the ACCESSORY or RUN position, the ignition
switch supplies voltage to fuse 13 in the fuse block
on circuit A48. Fuse 13 feeds circuit F85 which con-
nects to the cigar lighter. When the lighter is de-
pressed, the contacts inside of the lighter element
close and voltage flows to ground on circuit Z1.
HELPFUL INFORMATION
²In the ACCESSORY or RUN position, the ignition
switch connects circuit A1 from fuse 6 in the PDC
with circuit A48.
DIAGRAM INDEX
Component Page
Cigar Lighter...........................8W-41-3
Fuse 3 (PDC)...........................8W-41-2
Fuse 6 (PDC)...........................8W-41-3
Fuse 5 (Fuse Block).......................8W-41-2
Fuse 13 (Fuse Block)......................8W-41-3
Horns................................8W-41-2
Horn Relay.............................8W-41-2
Horn Switch............................8W-41-2
Ignition Switch..........................8W-41-3
J8W-41 HORN/CIGAR LIGHTERÐXJ-RHD 8W - 41 - 1

CONNECTOR LOCATIONS
GENERAL INFORMATION
This section provides illustrations identifying com-
ponent and connector locations in the vehicle. A con-nector index is provided. Use the wiring diagrams in
each section for connector number identification. Re-
fer to the index for the proper figure number.
CONNECTOR LOCATIONS
Connector # Color Location Fig.
C101......BK ...Front Left of Engine Compartment . .2
C102......BK ...InFront of Washer Fluid Reservoir . .2
C103......BK ...Bottom of Washer Fluid Reservoir . .2
C104......BK ...Bottom of Washer Fluid Reservoir . .2
C105......BK ...TopofWasher Fluid Reservoir.....2
C106......BK ...TopofRadiator Fan Housing......2
C107......BK ...Left Fender Side Shield.........2
C108......BK ...Left Fender Side Shield.........2
C109......BK ...Near Air Cleaner..............2
C110......BK ...Left Corner of Engine Compartment .2
C111......BK ...Rear of Intake Manifold.........4
C112......BK ...OnThrottle Body.............4
C113......BK ...OnThrottle Body.............4
C114......BK ...Rear of Intake Manifold.........4
C115......GN ...Lower Right of I.P.
C116......BK ...Near ABS Control Module
C117......GN ...Center of Dash Panel...........2
C118......BK ...Injector No. 6...............4
C119......BK ...Injector No. 5...............4
C120......BK ...Injector No. 4...............4
C121......BK ...Injector No. 3...............4
C122......BK ...Injector No. 2...............4
C123......BK ...Injector No. 1...............4
C124......BK ...OnEngine, Behind Power
Steering Pump.............4
C125......BK ...OnThermostat Housing.........4
C126......BK ...OnABSControl Module.........7
C127......BK ...Near ABS Control Module........7
C128......BK ...Near Distributor..............4
C129......BK ...Near Center of Dash Panel.......3
C130......GY ...Near Center of Dash Panel.......3
C131......BK ...Near Left Kick Panel
C132......BK ...OnSteering Column...........6
C133......BK ...Near Center of Dash Panel.......3
C134......BK ...Center of Dash Panel...........3
C135......BK ...Below Brake Master Cylinder......3
C136......BK ...Right Corner of Engine Compartment .3
C137......BK ...Right Side of Hood............3
C138......BK ...Near ABS Control Module
C139......BK ...Near ABS Control Module........7
C140......GY ...Near ABS Control Module........7
C141......GN ...Near ABS Control Module........7
C142......BK ...Right Fender Side Shield........3
C143......BK ...Right Fender Side Shield........3
C144......BK ...Right Fender Side Shield........3
C145......BK ...Right Fender Side Shield........3
C146......BK ...Below Battery................3
C147......BK ...Rear of Battery...............5
C148......BK ...AtStarter Motor..............4
C149......BK ...Right Side of Engine Near Distributor .4
C150......BK ...Rear of Generator.............4
C151......BK ...Rear of Generator.............5Connector # Color Location Fig.
C152......BK ...Behind Lens................1
C153......BK ...Left Rear of Radiator Closure Panel .1
C154......BK ...Behind Lens................1
C155......BK ...Behind Lens................1
C156......BK ...Behind Lens................1
C157......BK ...Center of Grille Opening.........1
C158......BK ...Center of Grille Opening.........1
C159......BK ...Behind Lens................1
C160......BK ...Behind Lens................1
C201......GY ...Center Bottom of I.P............8
C202......WT ...Center Bottom of I.P............8
C203......BK ...Behind Right Kick Panel........12
C204......BK ...Right Side of I.P.
C205......BK ...Left Rear of I.P...............8
C206......BK ...Left Rear of I.P...............8
C207......BK ...Near Right Kick Panel..........7
C208......GN ...Near Right Kick Panel..........7
C209......RD ...Behind Right Kick Panel........12
C210......BK ...Behind Fender Side Shield
C211......BK ...Near Right Kick Panel..........7
C212......BK ...Near Right Kick Panel
C213......BK ...Rear of Headlamp Switch.......10
C214......BK ...Rear of I.P., Right of Steering
Column..................9
C215......BK ...Rear of I.P., Right of Steering
Column..................9
C216......BK ...Rear of I.P., Right of Steering
Column.................9
C217......RD ...Rear of I.P., Right of Steering
Column..................9
C218......BK ...Below Stop Lamp Switch........7
C219......BK ...Rear of I.P., Right of Steering
Column.................9
C220......NAT ..Rear of I.P. Cluster...........10
C221......BK ...Rear of I.P. Cluster...........10
C222......NAT ..Rear of I.P., Left of Steering Column .9
C223......BK ...Rear of I.P., Left of Steering Column .9
C224......BK ...Rear of I.P., Left of Steering Column .9
C225......BK ...Rear of I.P., Left of Steering Column .9
C226......BK ...OnSteering Column...........6
C227......BK ...Near ABS Control Module........7
C228......WT ...Center of I.P.
C229......BK ...Center of I.P.
C230......BK ...OnSteering Column...........6
C231......BK ...OnSteering Column...........6
C232......BK ...OnSteering Column...........6
C233......BK ...Center Bottom of I.P............8
C234......BK ...Rear of I.P., Above Ash Receiver . . .8
C235......BK ...Rear of Radio...............9
C236......BR ...Rear of A/C-Heater Controls.....10
C237......BK ...Center Bottom of I.P............8
C238......BK ...Near ABS Control Module........7
J8W-90 CONNECTOR LOCATIONSÐXJ-RHD 8W - 90 - 1

FUEL/IGNITION
INDEX
page page
Automatic Shut Down (ASD) Relay............. 1
Battery Feed.............................. 2
Brake Switch Input......................... 5
Camshaft Position Sensor.................... 3
Crankshaft Position Sensor................... 3
Data Link Connector........................ 5
Diagram Index............................ 5
Engine Coolant Temperature Sensor............ 3
Fuel Injectors............................. 2
Fuel Pump Module......................... 2
Fuel Pump Relay.......................... 2
Heated Oxygen Sensor...................... 3Idle Air Control (IAC) Motor................... 2
Ignition Coil.............................. 2
Ignition Switch............................ 1
Intake Air Temperature Sensor................ 4
Malfunction Indicator Lamp (MIL)............... 5
Manifold Absolute Pressure Sensor............. 4
Park/Neutral Position Switch.................. 4
Power (Device) Ground...................... 5
Power Steering Pressure Switch............... 4
Tachometer Signal......................... 5
Throttle Position Sensor..................... 4
Vehicle Speed Sensor....................... 3
IGNITION SWITCH
Circuit A1 from fuse 4 in the Power Distribution
Center (PDC), supplies battery voltage to the ignition
switch. Depending upon position, the ignition switch
powers circuits A21, A22, A31, and A41.
START POSITION
In the START position, the ignition switch connects
circuit A1 to circuit A41. Circuit A41 connects to the
coil side of the starter motor relay.
Also in the START position, the case grounded ig-
nition switch provides ground for the brake lamp
switch and parking brake lamp switch on circuit G11.
START OR RUN POSITION
In the START and RUN position, the ignition
switch connects circuit A1 with circuit A21. The A21
circuit connects to fuses 5 and 9 in the fuse block.
Fuse 9 powers circuit G5. Fuse 5 powers circuit G50.
²Circuit G5 powers the buzzer module. Circuit G5
also splices to power the daytime running lamps
module (Canada only), A/C compressor clutch relay,
heated rear window relay, and the gauges and indi-
cator lamps in the instrument cluster.
RUN (ONLY) POSITION
When the ignition switch is in the RUN position, it
connects circuit A1 to circuit A22. Circuit A22 powers
fuses 1, 12, and 13 in the fuse block.
²Fuse 1 powers the rear wiper system on circuit
V23.
²Fuse 12 feeds the blower motor and air condition-
ing system on circuit C1.
²Fuse 13 feeds circuit F15 which powers the ABS
module and connects to the coil side of the ABS
power relay.
ACCESSORY OR RUN POSITION
In the ACCESSORY or RUN position, the ignition
switch connects circuit A1 to circuit A31. Circuit A31
connects to a bus bar in the fuse block that feeds
fuses 4 and 7 along with the circuit breaker in cavity
11 .
²Fuse 4 powers circuit L5 which feeds the turn sig-
nal flasher.
²Fuse 7 powers circuit F30. Circuit F30 supplies
power to the radio, radio relay, and the cigar lighter.
²The circuit breaker in cavity 11 powers the V6 cir-
cuits which feed the wiper switch and wiper motor.
AUTOMATIC SHUT DOWN (ASD) RELAY
When the ignition switch is in either the START or
RUN position, it connects circuit A1 from fuse 4 in
the Power Distribution Center (PDC) to circuit A21.
Circuit A21 powers fuse 5 in the fuse block. Circuit
G50 from fuse 5 splices to power the coil side of the
Automatic Shut Down (ASD) relay. The Powertrain
Control Module (PCM) provides ground for the relay
on circuit K51. Circuit K51 connects to cavity 51 of
the PCM.
When the PCM grounds the ASD relay, contacts in-
side the relay close and connect circuit A14 from fuse
1 in the PDC to circuit A142. Circuit A142 splices to
the generator field terminal, fuel injectors, ignition
coil, and heated oxygen sensor. Circuit A142 also con-
nects to cavity 57 of the PCM.
Circuit A14 from fuse 1 in the PDC supplies bat-
tery voltage to the contact side of the ASD relay.
HELPFUL INFORMATION
²Along with supplying voltage to the ASD relay
contacts, circuit A14 supplies voltage to the contact
side of the fuel pump relay.
²Circuit G50 also supplies battery voltage to the
coil side of the fuel pump relay.
²Circuit A14 also connects to cavity 3 of the PCM.
J8W-30 FUEL/IGNITIONÐYJ VEHICLES 8W - 30 - 1

The PCM provides a ground for the engine coolant
temperature sensor signal (circuit K2) through circuit
K4. Circuit K4 connects to cavity 4 of the PCM con-
nector.
HELPFUL INFORMATION
Circuit K4 splices to supply ground for the signals
from the following:
²Heated oxygen sensor
²Camshaft position sensor
²Crankshaft position sensor
²Intake air temperature sensor
²Throttle position sensor
²Manifold absolute pressure sensor
²Vehicle speed sensor
THROTTLE POSITION SENSOR
From the Powertrain Control Module (PCM), cir-
cuit K6 supplies 5 volts to the Throttle Position Sen-
sor (TPS). Circuit K6 connects to cavity 6 of the
PCM.
Circuit K22 delivers the TPS signal to the PCM.
Circuit K22 connects to cavity 22 of the PCM.
The PCM provides a ground for the throttle posi-
tion sensor signal (circuit K22) through circuit K4.
Circuit K4 connects to cavity 4 of the PCM.
HELPFUL INFORMATION
Refer to Group 14 for throttle position sensor oper-
ation.
Circuit K6 splices to supply 5 volts to the Manifold
Absolute Pressure (MAP) sensor.
Circuit K4 splices to supply ground for the signals
from the following:
²Heated oxygen sensor
²Camshaft position sensor
²Crankshaft position sensor
²Intake air temperature sensor
²Manifold absolute pressure sensor
²Engine coolant temperature sensor
²Vehicle speed sensor
MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR
From the Powertrain Control Module (PCM), cir-
cuit K6 supplies 5 volts to the Manifold Absolute
Pressure (MAP) sensor. Circuit K6 connects to cavity
6 of the PCM.
Circuit K1 delivers the MAP signal to the PCM.
Circuit K1 connects to cavity 1 of the PCM.
The PCM provides a ground for the MAP sensor
signal (circuit K1) through circuit K4. Circuit K4 con-
nects to cavity 4 of the PCM.
HELPFUL INFORMATION
Refer to Group 14 for MAP sensor operation.
Circuit K6 splices to supply 5 volts to the throttle
position sensor.Circuit K4 splices to supply ground for the signals
from the following:
²Heated oxygen sensor
²Camshaft position sensor
²Crankshaft position sensor
²Intake air temperature sensor
²Throttle position sensor
²Engine coolant temperature sensor
²Vehicle speed sensor
INTAKE AIR TEMPERATURE SENSOR
The intake air temperature sensor provides an in-
put to the Powertrain Control Module (PCM) on cir-
cuit K21. Circuit K21 connects to cavity 21 of the
PCM.
From circuit K21, the intake air temperature sen-
sor draws voltage from the PCM. The sensor is a
variable resistor. As intake air temperature changes,
the resistance in the sensor changes, causing a
change in current draw.
The PCM provides a ground for the intake air tem-
perature sensor signal (circuit K21) through circuit
K4. Circuit K4 connects to cavity 4 of the PCM.
HELPFUL INFORMATION
Circuit K4 splices to supply ground for the signals
from the following:
²Heated oxygen sensor
²Camshaft position sensor
²Crankshaft position sensor
²Throttle position sensor
²Manifold absolute pressure sensor
²Engine coolant temperature sensor
²Vehicle speed sensor
PARK/NEUTRAL POSITION SWITCH
When closed, the case-grounded park/neutral posi-
tion switch provides a ground path on circuit T41 for
the coil side of the starter motor relay. Circuit A41
from the ignition switch provides battery voltage to
the coil side of the relay.
Circuit T41 splices to cavity 30 of the Powertrain
Control Module (PCM). The park/neutral position
switch provides an input to the (PCM).
HELPFUL INFORMATION
²In the START position, the ignition switch con-
nects circuit A1 from the Power Distribution Center
(PDC) to circuit A41. Fuse 4 in the fuse block pro-
tects circuits A1 and A41.
²The Park/Neutral position switch and back-up
lamp switch are molded together.
POWER STEERING PRESSURE SWITCH
The Powertrain Control Module (PCM) supplies
voltage to the power steering pressure switch on cir-
cuit K10. Circuit Z1 provides ground for the switch.
When the switch closes, voltage flows through the
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