sensor JEEP YJ 1995 Service And Manual PDF

OVERHEAD CONSOLE
OVERHEAD CONSOLE
When the ignition switch is in the START or RUN
position, it connects circuit A1 from fuse 6 in the
Power Distribution Center (PDC) to circuit A21. Cir-
cuit A21 supplies power to circuit F87 through fuse
17 in the fuse block. Circuit F87 supplies power to
the overhead console.
When the headlamps or parking lamps are ON, cir-
cuits L90 and E2 provide voltage to the overhead
console for illumination. Voltage on circuit L90 in-
forms the overhead console that the headlamps or
parking lamps are ON. Circuit E2 from fuse 19 in
the fuse block powers the illumination lamps in the
overhead console. Circuit E2 originates at the head-
lamp switch.
Circuits Z1 and Z2 provides ground for the over-
head console. From circuit M2, the overhead console
senses when one of the door jamb switches opens.
AMBIENT TEMPERATURE SENSOR
The ambient temperature sensor is a variable re-
sistor. Circuit G31 supplies voltage from the over-
head console to the sensor. Circuit G32 is the signal
return from the sensor to the overhead console.
LAMPS
Circuit M1 supplies voltage for the case grounded
reading lamps in the overhead console. The ignition
off draw (IOD) fuse (fuse 9) in the fuse block supplies
voltage to circuit M1. Circuit A6 from fuse 16 in PDC
feeds the IOD fuse. Circuit A7 from fuse 3 in the
PDC supplies voltage to fuse 1 in the PDC.
DIAGRAM INDEX
Component Page
Ambient Temperature Sensor.................8W-49-4
Chime/Buzzer Module......................8W-49-2
Fuse 1 (PDC)...........................8W-49-2
Fuse 3 (PDC)...........................8W-49-2
Fuse 5 (PDC)...........................8W-49-2
Fuse 9 (Fuse Block).......................8W-49-2
Fuse 15 (Fuse Block)......................8W-49-3
Fuse 16 (PDC)..........................8W-49-2
Fuse 17 (Fuse Block)......................8W-49-2
Fuse 19 (Fuse Block)......................8W-49-3
Headlamp Delay Module....................8W-49-2
Headlamp Switch.........................8W-49-3
Ignition Switch..........................8W-49-2
Instrument Cluster........................8W-49-4
Overhead Console......................8W-49-3, 4
Overhead Console........................8W-49-2
Telltale Connector (Instrument Cluster)...........8W-49-2
J8W-49 OVERHEAD CONSOLEÐXJ VEHICLES 8W - 49 - 1

Circuit L39 supplies voltage to the fog lamps. Cir-
cuit Z1 provides ground for the fog lamps.
If the high beam lamps are ON, circuit G465 ener-
gizes the high beam relay. When the high beam relay
energizes, the contacts open and power is not sup-
plied to the fog lamps. Circuit Z1 provides ground for
the coil side of the high beam relay.
Circuit E2 provides voltage for the illumination
lamp in the fog lamp switch.
HELPFUL INFORMATION
²Circuit L3 splices to power circuit G465. Circuit
L3 powers the high beam circuit of the headlamps.
HEADLAMP DELAY MODULE
When the operator turns off the ignition switch and
the headlamp switch, the headlamp delay module
powers the headlamps for approximately 45 seconds.
When the ignition switch is in the RUN position,
circuit A21 powers circuit F87 through fuse 17 in the
fuse block. Circuit F87 supplies the IGNITION ON/
OFF signal to the headlamp delay module. Circuit Z1
provides ground for the module.
When the headlamp delay module activates, it con-
nects circuit X4 from fuse 11 in the fuse block to cir-
cuit F34. Circuit F34 powers the headlamps through
the headlamp dimmer switch circuit L3.
HELPFUL INFORMATION
Circuit A7 from fuse 3 in the PDC supplies voltage
to the fuse block bus bar that powers circuit X4
through the fuse in cavity 11.
DAYTIME RUNNING LAMP (DRL) MODULE
On vehicles built for sale in Canada, the low-beam
headlamps operate when the ignition switch is in the
RUN position.
When the ignition switch is in the RUN position,
circuit A1 from fuse 6 in the Power Distribution Cen-
ter (PDC), connects to circuit A21. Circuit A21 splices
to supply power to the DRL module.
Circuit A3 from fuse 5 in the PDC connects to DRL
module. Circuit A3 is HOT at all times.The DRL module receives the vehicle speed sensor
input from circuit G7. Circuit G465 from the DRL
module splices to circuit L3 to provide power for the
high beam indicator lamp in the instrument cluster.
Circuit L4 powers the low beams of the left and
right headlamps. When the headlamp switch is OFF,
the DRL module powers the low beams on circuit L4.
When the headlamps are ON, the dimmer switch in
the multi-function switch powers the low beams on
circuit L4.
Circuit L3 feeds the high beams of the headlamps.
When the operator flashes the headlamps with the
stalk of the multi-function switch, the DRL senses
voltage on circuit L3. When it senses voltage on cir-
cuit L3, the DRL module stops supplying power to
the low beams on circuit L4.
Circuit Z12 provides ground for the DRL module.
DIAGRAM INDEX
Component Page
Chime/Buzzer Module......................8W-50-8
Daytime Running Lamps (DRL) Module..........8W-50-3
Fog Lamps.............................8W-50-7
Fog Lamp Switch........................8W-50-7
Fuse 3 (PDC)...........................8W-50-9
Fuse 4 (Fuse Block).......................8W-50-9
Fuse 5 (PDC).....................8W-50-2, 3, 6, 9
Fuse 6 (PDC).........................8W-50-2, 8
Fuse 7 (PDC)...........................8W-50-6
Fuse 11 (Fuse Block)......................8W-50-9
Fuse 13 (PDC)..........................8W-50-6
Fuse 15 (Fuse Block)....................8W-50-3, 6
Fuse 17 (Fuse Block)......................8W-50-8
Fuse 19 (Fuse Block)......................8W-50-6
Headlamps.............................8W-50-5
Headlamp Dimmer Switch.................8W-50-4, 9
Headlamp Switch.....................8W-50-4, 6, 9
High Beam Relay.........................8W-50-7
Ignition Switch........................8W-50-3, 8
Park Lamp Relay.........................8W-50-6
Side Marker Lamps.......................8W-50-5
Tail, Stop and Turn Signal Lamps..............8W-50-5
Telltale Connector (Instrument Cluster)...........8W-50-9
8W - 50 - 2 8W-50 FRONT LIGHTINGÐXJ VEHICLESJ

Fig. 19 ABS Sensors Wiring Connections
Fig. 20 Rear Compartment Wiring Connectors
J8W-90 CONNECTOR LOCATIONSÐXJ VEHICLES 8W - 90 - 21

SPLICE LOCATIONS
GENERAL INFORMATION
This section provides illustrations identifying the
general location of the splices in this vehicle. A splice
index is provided. Use the wiring diagrams in each
section for splice number identification. Refer to the
index for the proper splice number.
SPLICE LOCATIONS
Splice
NumberLocations Fig.
S101 Near Generator T/O..................4
S102 Near Bulkhead T/O...................2
S103 Near Bulkhead T/O...................2
S104 Near Bulkhead T/O...................2
S105 Near Bulkhead T/O...................2
S106 Near Bulkhead T/O...................1
S107 Near Wiper Motor T/O................1
S108 Near Wiper Motor T/O................1
S109 Near Wiper Motor T/O................1
S110 Center of Dash Panel Near Grommet.......1
S111 Near T/O for ABS Diode...............7
S112 Near T/O for Map Sensor..............1
S113 Near T/O for Injector #5 and #6..........4
S114 Near T/O for Injector #5 and #6..........4
S115 Near T/O for Injector #5 and #6..........4
S116 Near T/O for Injector #5 and #6..........4
S117 Near T/O for Map Sensor..............1
S118 Near T/O for Map Sensor..............1
S119 Near Distributor T/O..................1
S120 Between Distributor T/O and Underhood
Lamp T/O.......................1
S121 Between Distributor T/O and Underhood
Lamp T/O.......................1
S122 Between Distributor T/O and Underhood
Lamp T/O.......................1
S123 RT Side of Cowl Panel................1
S124 RT Side of Cowl Panel................1
S125 Near T/O for PDC...................1
S126 Near T/O for Oil Pressure Switch..........5
S127 Near Generator T/O..................5
S128 LT Side of Grille Panel................3
S129 LT Side of Grille Panel................3
S130 Center of Grille Panel.................3
S201 Near Body Harness Connector T/O.........6
S202 Near Body Harness Connector T/O.........6
S203 Near Body Harness Connector T/O.........6
S204 Near Relay Center...................6
S205 Near T/O for Headlamp Switch...........6Splice
NumberLocations Fig.
S206 Near T/O for Telltale..................6
S207 Near T/O for Cluster..................6
S208 Near T/O for Cluster..................6
S209 Right Side of Cluster.................6
S210 Right Side of Cluster.................6
S211 Near Instrument Panel Ground T/O........6
S212 Near Wiper Switch T/O................6
S213 Near Antenna T/O...................7
S214 Near Blower Resistor T/O..............7
S215 Right Side of Instrument Panel...........7
S301 In Left Rear Door T/O.................8
S302 Near Left C-Pillar....................8
S303 Near Left C-Pillar....................8
S304 Near Left C-Pillar....................8
S305 Near Left C-Pillar....................8
S306 Near Left C-Pillar....................8
S307 Left Rear Wheel Well................10
S308 Left Rear Wheel Well................10
S309 Near Left Rear Door T/O...............8
S310 Near Left Rear Door T/O...............8
S311 Left Side of Floor Tunnel...............9
S312 Top of Floor Tunnel..................9
S313 In Power Mirror Switch T/O.............9
S314 Right A- Pillar.....................11
S315 Near RT Vanity Mirror T/O.............11
S316 Near RT Vanity Mirror T/O.............11
S317 In Trailer Tow Harness Near Grommet......14
S318 In Trailer Tow Harness Near Grommet......14
S319 In Liftgate.......................13
S320 Right A-Pillar.....................11
S321 In Left Front Door..................12
S401 In Left Rear Tail Lamp..........Not Shown
S402 In Right Rear Tail Lamp.........Not Shown
S403 In Left Rear Tail Lamp..........Not Shown
S404 In Right Rear Tail Lamp.........Not Shown
J8W-95 SPLICE LOCATIONSÐXJ VEHICLES 8W - 95 - 1

CHARGING SYSTEM
CHARGING SYSTEM
The charging system is an integral part of the bat-
tery and starting systems. Because all these systems
work in conjunction, diagnose and test them together.
Circuit A11 connects to the generator output termi-
nal and splices to fuse 1 and fuse 9 in the Power Dis-
tribution Center (PDC). Circuit A0 connects the
battery to the PDC. Circuit Z0 provides ground for
the generator.
When the ignition switch is in either the START or
RUN positions, it connects circuit A1 from fuse 6 in
the PDC to circuit A21. Circuit A21 splices to supply
current to 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 A18 from fuse
14 in the PDC to circuit A142. Circuit A142 splices to
the generator field terminal.
The PCM has an internal voltage regulator that
controls generator output. The PCM controls the gen-
erator field on circuit K20. Circuit K20 connects to
PCM cavity 20.When the engine operates and there is current in
the generator field, the generator produces a B+ volt-
age. The generator supplies B+ voltage to the battery
through the A11 and A0 circuits.
HELPFUL INFORMATION
²Circuit A14 from fuse 2 in the PDC supplies volt-
age to PDC fuse 14.
²The ignition switch also connects circuit A1 with
circuits A41, A38, and A48.
²Circuit A21 also powers the coil side of the fuel
pump relay.
²The ASD relay supplies battery voltage for the fuel
injectors, ignition coil, and the heated oxygen sensor.
The fuel pump relay powers the fuel pump module.
²Circuit K51 also provides ground for the coil side
of the fuel pump relay.
DIAGRAM INDEX
Component Page
Battery...............................8W-20-2
PDC Fuse 1............................8W-20-2
PDC Fuse 9............................8W-20-2
Generator..............................8W-20-2
Powertrain Control Module..................8W-20-2
J8W-20 CHARGING SYSTEMÐXJ-RHD 8W - 20 - 1

FUEL/IGNITION
INDEX
page page
Automatic Shut Down (ASD) Relay............. 1
Battery Feed.............................. 1
Brake Switch Input......................... 5
Camshaft Position Sensor.................... 3
Crankshaft Position Sensor................... 3
Data Link Connector........................ 4
Diagram Index............................ 5
Engine Coolant Temperature Sensor............ 3
Fuel Injectors............................. 1
Fuel Pump Module......................... 2
Fuel Pump Relay.......................... 2
Heated Oxygen Sensor...................... 3Idle Air Control (IAC) Motor................... 2
Ignition Coil.............................. 2
Ignition Feed............................. 1
Ignition Switch............................ 1
Intake Air Temperature Sensor................ 4
Malfunction Indicator Lamp (MIL)............... 4
Manifold Absolute Pressure Sensor............. 4
Park/Neutral Position Switch.................. 4
Power (Device) Ground...................... 5
Tachometer Signal......................... 4
Throttle Position Sensor..................... 4
Vehicle Speed Sensor....................... 2
IGNITION SWITCH
Circuit A1 from fuse 11 in the power distribution
center (PDC), supplies battery voltage to the ignition
switch. Depending upon position, the ignition switch
powers circuits A21, A38, A41, or A48.
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.
Additionally in the START position, the case
grounded ignition switch provides ground for the
brake lamp switch and the warning lamps in the in-
strument cluster.
START OR RUN POSITION
In the START or RUN position, the ignition switch
connects circuit A1 to circuit A21. Circuit A21 splices
to power the coil side of the Automatic Shut Down
(ASD) relay and the fuel pump relay.
RUN (ONLY) POSITION
When the ignition switch is in the RUN position, it
connects circuit A1 to circuit A38. Circuit A38 feeds
circuit L39.
ACCESSORY OR RUN POSITIONS
In the ACCESSORY or RUN positions, the ignition
switch connects circuit A1 to circuit A48. Circuit A48
connects to a bus bar in the fuse block.
AUTOMATIC SHUT DOWN (ASD) RELAY
When the ignition switch is in either the START or
RUN positions, it connects circuit A1 from fuse 6 in
the Power Distribution Center (PDC) to circuit A21.
Circuit A21 supplies battery voltage to the coil side of
the Automatic Shut Down (ASD) relay. The Power-train 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 A18 from fuse
14 in the PDC to circuit A142. Circuit A142 splices to
the generator field terminal, fuel injectors, and igni-
tion coil. Circuit A142 also connects to cavity 57 of
the PCM.
HELPFUL INFORMATION
²Along with supplying voltage to the coil side of the
ASD relay, circuit A21 also supplies voltage to the
coil side of the fuel pump relay.
²Circuit A21 also connects to cavity 9 of the PCM.
BATTERY FEED
Circuit A14 from fuse 2 in the power distribution
center supplies battery voltage to cavity 3 of the
Powertrain Control Module (PCM).
HELPFUL INFORMATION
Circuit A14 also supplies power to the contact sides
of the fuel pump relay and fuse F2 in the PDC. Fuse
F2 powers circuit A18 which supplies voltage to the
contact side of the automatic shut down relay.
IGNITION FEED
When the ignition switch is in either the START or
RUN positions, it connects circuit A1 from fuse 6 in
the Power Distribution Center (PDC) to circuit A21.
Circuit A21 also connects to cavity 9 of the PCM and
provides the ignition input.
FUEL INJECTORS
When the Automatic Shut Down (ASD) relay con-
tacts close, they connect circuits A18 and A142. Cir-
J8W-30 FUEL/IGNITIONÐXJ-RHD 8W - 30 - 1

cuit A142 supplies voltage to the fuel injectors. Each
injector has a separate ground circuit controlled by
the PCM.
Circuit K11 provides ground for injector number
one. The K11 circuit connects to cavity 16 of the
PCM.
Circuit K12 provides ground for injector number
two. The K12 circuit connects to cavity 15 of the
PCM.
Circuit K13 provides ground for injector number
three. The K13 circuit connects to cavity 14 of the
PCM.
Circuit K14 provides ground for injector number
four. The K14 circuit connects to cavity 13 of the
PCM.
Circuit K15 provides ground for injector number
five. The K15 circuit connects to cavity 38 of the
PCM.
Circuit K16 provides ground for injector number
six. The K16 circuit connects to cavity 58 of the
PCM.
HELPFUL INFORMATION
²Circuit A142 splices to supply voltage to the fuel
injectors, ignition coil, PCM, generator.
²For information about fuel injector operation, refer
to Group 14.
IGNITION COIL
When the Automatic Shut Down (ASD) relay con-
tacts close, they connect circuits A18 and A142. Cir-
cuit A142 splices to supply voltage to the ignition
coil. The PCM controls the ground path for the igni-
tion coil on circuit K19. Circuit K19 connects to cav-
ity 19 of the PCM.
HELPFUL INFORMATION
Circuit A142 splices to supply voltage to the fuel
injectors, ignition coil, PCM, and generator.
FUEL PUMP RELAY
When the ignition switch is in either the START or
RUN positions, it connects circuit A1 from fuse 6 in
the Power Distribution Center (PDC) to circuit A21.
Circuit A21 supplies battery voltage to the coil side of
the fuel pump 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 fuel pump relay, con-
tacts inside the relay close and connect circuit A14
from fuse 14 in the PDC to circuit A141. Circuit A141
connects to circuit A241. Circuit A241 supplies volt-
age to the fuel pump motor (part of the in-tank fuel
pump module).
HELPFUL INFORMATION
²Circuit A14 also splices to supply battery voltage
to cavity 3 of the PCM.²Circuit A141 also supplies battery voltage to the
heated oxygen sensor.
FUEL PUMP MODULE
FUEL PUMP MOTOR
When the fuel pump relay contacts close, the relay
supplies voltage to the fuel pump motor. Circuit A141
from the relay supplies voltage to circuit A241. Cir-
cuit A241 connects to circuit F9 in the fuel pump mo-
tor. Circuit Z1 provides ground for the fuel pump
motor.
FUEL LEVEL SENSOR
The fuel level sensor is a variable resistor. Circuit
G4 connects the fuel level sensor to the fuel gauge in
the instrument cluster. Circuit F87 from fuse 26 in
the fuse block supplies voltage to the fuel gauge. The
fuel level sensor draws voltage from circuit F87
through the fuel gauge on circuit G4. Circuit G4 con-
nects to the fuel level sensor.
Circuit Z1 provides the ground path for the fuel
level sensor.
HELPFUL INFORMATION
As current flows through the coils in the fuel
gauge, it creates a magnetic field. One of the coils in
the gauge receives fixed current. The other coil is
connected to the level sensor. The magnetic field con-
trols the position of the fuel gauge pointer.
The fuel level sensor contains a variable resistor.
As the position of the float arm on the fuel level sen-
sor changes, the resistor changes the current flow
through second coil in the fuel gauge. A change in
current flow alters the magnetic field in the fuel
gauge, which changes the pointer position.
IDLE AIR CONTROL (IAC) MOTOR
The Powertrain Control Module (PCM) operates
the idle air control motor through 4 circuits - K39,
K40, K59, and K60. Each circuit connects to separate
cavities in the PCM connector.
²Circuit K39 connects to cavity 39 of the PCM
²Circuit K40 connects to cavity 40 of the PCM
²Circuit K59 connects to cavity 59 of the PCM
²Circuit K60 connects to cavity 60 of the PCM
VEHICLE SPEED SENSOR
Circuit K7 supplies 8 volts from the Powertrain
Control Module (PCM) to the vehicle speed sensor.
The K7 circuit connects to cavity 7 of the PCM.
Circuit G7 from the vehicle speed sensor provides
an input signal to the PCM. The G7 circuit connects
to cavity 47 of the PCM.
The PCM provides a ground for the vehicle speed
sensor signal (circuit G7) through circuit K4. Circuit
K4 connects to cavity 4 of the PCM.
8W - 30 - 2 8W-30 FUEL/IGNITIONÐXJ-RHDJ

HELPFUL INFORMATION
²Circuit G7 splices to the speedometer.
²Circuit K7 splices to supply 8 volts to the camshaft
position sensor and crankshaft position sensor.
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
²Intake air temperature sensor
HEATED OXYGEN SENSOR
When the fuel pump relay contacts close, they con-
nect circuits A14 and A141. Circuit A141 splices to
supply voltage to the heated oxygen sensor.
Circuit K41 delivers the signal from the heated ox-
ygen sensor to the PCM. Circuit K41 connects to cav-
ity 41 of the PCM.
The PCM provides a ground for the heated oxygen
sensor signal (circuit K41) through circuit K4. Circuit
K4 connects to cavity 4 of the PCM connector.
Circuit Z12 provides a ground for the heater circuit
in the sensor.
HELPFUL INFORMATION
²Circuit A141 also supplies battery voltage to the
fuel pump.
Circuit K4 splices to supply ground for the signals
from the following:
²Camshaft position sensor
²Crankshaft position sensor
²Intake air temperature sensor
²Throttle position sensor
²Manifold absolute pressure sensor
²Engine coolant temperature sensor
²Vehicle speed sensor
CAMSHAFT POSITION SENSOR
The Powertrain Control Module (PCM) supplies 8
volts to the camshaft position sensor (in distributor)
on circuit K7. Circuit K7 connects to cavity 7 of the
PCM.
The PCM receives the camshaft position sensor sig-
nal on circuit K44. Circuit K44 connects to cavity 44
of the PCM.
The PCM provides a ground for the camshaft posi-
tion sensor signal (circuit K44) through circuit K4.
Circuit K4 connects to cavity 4 of the PCM.
HELPFUL INFORMATION
²Circuit K7 splices to supply 8 volts to the crank-
shaft position sensor and the vehicle speed sensor.
Circuit K4 splices to supply ground for the signals
from the following:
²Heated oxygen sensor²Crankshaft position sensor
²Intake air temperature sensor
²Throttle position sensor
²Manifold absolute pressure sensor
²Engine coolant temperature sensor
²Vehicle speed sensor
CRANKSHAFT POSITION SENSOR
The Powertrain Control Module (PCM) supplies 8
volts to the crankshaft position sensor on circuit K7.
Circuit K7 connects to cavity 7 of the PCM.
The PCM receives the crankshaft position sensor
signal on circuit K24. Circuit K24 connects to cavity
24 of the PCM.
The PCM provides a ground for the crankshaft po-
sition sensor (circuit K24) through circuit K4. Circuit
K4 connects to cavity 4 of the PCM.
HELPFUL INFORMATION
²Circuit K7 splices to supply 8 volts to the camshaft
position sensor and the vehicle speed sensor.
Circuit K4 splices to supply ground for the signals
from the following:
²Heated oxygen sensor
²Camshaft position sensor
²Intake air temperature sensor
²Throttle position sensor
²Manifold absolute pressure sensor
²Engine coolant temperature sensor
²Vehicle speed sensor
ENGINE COOLANT TEMPERATURE SENSOR
The engine coolant temperature sensor provides an
input to the
Powertrain Control Module (PCM) on circuit K2.
From circuit K2, the engine coolant temperature sen-
sor draws up to 5 volts from the PCM. The sensor is
a variable resistor. As coolant temperature changes,
the resistance in the sensor changes, causing a
change in current draw. The K2 circuit connects to
cavity 2 of the PCM.
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
J8W-30 FUEL/IGNITIONÐXJ-RHD 8W - 30 - 3

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 sensor.
Circuit K22 splices to the transmission control
module.
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 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 PCM. The
park/neutral position switch provides an input to the
Powertrain Control Module (PCM).
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 Powertrain Control Module (PCM) provides
ground for the instrument cluster malfunction indica-
tor lamp on circuit G3. The MIL displays the mes-
sage CHECK ENGINE when illuminated. Circuit
F87 provides voltage for the lamp. Circuit G3 con-
nects to cavity 32 of the PCM.
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 also connects to cavity 5 of the
PCM.
8W - 30 - 4 8W-30 FUEL/IGNITIONÐXJ-RHDJ

HELPFUL INFORMATION
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.
BRAKE SWITCH INPUT
Circuit K29 provides the brake switch input to the
PCM. Circuit K29 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.
DIAGRAM INDEX
Component Page
Automatic Shut Down Relay.................8W-30-6
Camshaft Position Sensor...................8W-30-8
Crankshaft Position Sensor..................8W-30-9
Data Link Connector......................8W-30-11
Distributor Ignition Coil....................8W-30-11
Engine Coolant Temperature Sensor.............8W-30-9
Fuel Injector #1.........................8W-30-7
Fuel Injector #2.........................8W-30-7
Fuel Injector #3.........................8W-30-7
Fuel Injector #4.........................8W-30-7
Fuel Injector #5.........................8W-30-7
Fuel Injector #6.........................8W-30-7
Fuel Pump Relay........................8W-30-12
Fuel Tank Gauge Level Sending Unit...........8W-30-12
Fuse 2 (PDC)...........................8W-30-6
Fuse 6 (PDC)...........................8W-30-6
Fuse 11 (PDC).......................8W-30-6, 11
Fuse 14 (PDC)..........................8W-30-6
Heated Oxygen Sensor....................8W-30-10
Idle Air Control Motor.....................8W-30-10
Ignition Switch.......................8W-30-6, 12
Instrument Cluster....................8W-30-11, 12
Intake Air Temperature Sensor................8W-30-9
MAP Sensor............................8W-30-8
Powertrain Control Module.............8W-30-6 thru 12
Throttle Position Sensor....................8W-30-8
Vehicle Speed Sensor.....................8W-30-11
J8W-30 FUEL/IGNITIONÐXJ-RHD 8W - 30 - 5