1995 JEEP YJ ignition

switch to ground on circuit Z1. The switch closes dur-
ing periods of high power steering pump load and
low engine speed; such as parking maneuvers. Cir-
cuit K10 connects to cavity 10 of the PCM.
TACHOMETER SIGNAL
The Powertrain Control Module (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 G5
provides voltage for the lamp.
DATA LINK CONNECTOR
Circuit G50 supplies battery voltage to the data
link connector. Circuit G50 originates at fuse 5 in the
fuse block. Circuit G50 is double crimped at the data
link connector and connects to cavity 9 of the Power-
train Control Module (PCM).
Circuit A21 from the ignition switch powers fuse 5
when the switch is in the START or RUN positions.
In the START or RUN position the ignition switch
connects circuit A1 from fuse 4 in the Power Distri-
bution Center (PDC) with circuit A21.
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 splices to circuit Z1 which termi-
nates 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 Z1 and Z11 cir-
cuits at the right rear of the engine, the vehicle will
not operate. Check the connection at the ganged-
ground circuit eyelet.
BRAKE SWITCH INPUT
Circuit V40 provides the brake switch input to the
Powertrain Control Module (PCM). Circuit V40 con-
nects to cavity 29 of the PCM.
POWER (DEVICE) GROUND
Circuit Z11 connects to cavities 11 and 12 of the
Powertrain Control Module (PCM). The Z1 circuit
provides ground for PCM internal drivers that oper-
ate high current devices like the injectors and igni-
tion 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 Z1 is the right rear
of the engine.
²If the system loses ground for the Z1 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, 14
Camshaft Position Sensor................8W-30-10, 16
Crankshaft Position Sensor...............8W-30-10, 16
Data Link Connector...................8W-30-11, 17
Daytime Running Lamps (DRL) Module.......8W-30-11, 17
Engine Coolant Temperature Sensor..........8W-30-9, 18
Fuel Pump Relay........................8W-30-20
Fuel Tank Level Unit......................8W-30-21
Fuse 1 (PDC)........................8W-30-6, 14
Fuse 4 (PDC)........................8W-30-6, 14
Fuse 5 (Fuse Block).................8W-30-6, 14, 20
Heated Oxygen Sensor..................8W-30-7, 15
Idle Air Control Motor..................8W-30-12, 18
Ignition Switch.....................8W-30-6, 14, 20
Ignition Coil........................8W-30-12, 18
Injectors (4.0L).........................8W-30-13
Injectors (2.5L)..........................8W-30-8
Instrument Cluster....................8W-30-11, 17
Intake Air Temperature Sensor.............8W-30-9, 18
MAP Sensor.........................8W-30-9, 18
Power Steering Pressure Switch..............8W-30-12
Powertrain Control Module.............8W-30-6 thru 21
Throttle Position Sensor.................8W-30-9, 18
Vehicle Speed Sensor..................8W-30-11, 17
J8W-30 FUEL/IGNITIONÐYJ VEHICLES 8W - 30 - 5

TRANSMISSION CONTROLS
TORQUE CONVERTER CLUTCH (TCC) SOLENOID
AND RELAY
The TCC solenoid is only used on three-speed au-
tomatic transmissions. The Powertrain Control Mod-
ule (PCM) operates the TCC solenoid by energizing
the TCC relay.
Circuit G50 from fuse 5 in the Power Distribution
Center (PDC) supplies voltage to the coil side of the
TCC relay. When the PCM provides a ground path on
circuit K54, the relay contacts close.
When the relay contacts close, they connect circuit
A14 from fuse 1 in the PDC 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.
²Circuit A21 powers fuse 5 in the fuse block.
²Circuit G50 also connects to the engine data link
connector, Automatic Shut Down (ASD) relay, and
fuel pump relay.
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.
DIAGRAM INDEX
Component Page
Fuse 1 (PDC)...........................8W-31-2
Fuse 4 (PDC)...........................8W-31-2
Fuse 5 (Fuse Block).......................8W-31-2
Ignition Switch..........................8W-31-2
Instrument Cluster........................8W-31-2
Powertrain Control Module (PCM)..............8W-31-2
TCC Relay.............................8W-31-2
TCC Solenoid...........................8W-31-2
J8W-31 TRANSMISSION CONTROLSÐYJ VEHICLES 8W - 31 - 1

ANTI-LOCK BRAKES
GENERAL INFORMATION
Three fuses supply power for the Anti-Lock Brake
System (ABS); fuses 9 and 10 in the PDC and fuse
13 in the fuse block. Fuses 9 and 10 in the Power
Distribution Center (PDC) are connected directly to
battery voltage and are HOT all times. Fuse 13 is
HOT when the ignition switch is the RUN position.
In the RUN position, the ignition switch connects
circuit A1 from fuse 4 in the PDC with circuit A22.
Circuit A22 connects to a bus bar in the fuse block.
The bus bar feeds circuit F15 through fuse 13. Fuse
13 is a 2 amp fuse.
Circuit F15 splices to the coil side of the ABS
power relay and cavity 53 of the ABS control module.
Circuit Z1 provides ground for the ABS control
module. Circuit Z1 connects to cavities 1 and 19 of
the ABS control module.
Refer to group 5, Brakes for operational descrip-
tions of ABS system components.
WHEEL SPEED SENSORS
The all wheel anti-lock system uses four wheel
speed sensors; one for each wheel. Each sensor con-
verts wheel speed into an electrical signal that it
transmits to the ABS control module. A pair of
twisted wires connect to each sensor to provide sig-
nals to the ABS control module.
Circuits B6 and B7 provide signals to ABS control
module from the right front wheel speed sensor. Cir-
cuit B6, which provides the LOW signal, connects to
cavity 29 of the ABS control module. Circuit B7 con-
nects to cavity 47 of the module and provides the
HIGH signal.
Circuits B8 and B9 provide signals to ABS control
module from the left front wheel speed sensor. Cir-
cuit B8, which provides the LOW signal, connects to
cavity 30 of the ABS control module. Circuit B9 con-
nects to cavity 48 of the module and provides the
HIGH signal.
Circuits B1 and B2 provide signals to ABS control
module from the right rear wheel speed sensor. Cir-
cuit B1 which provides the LOW signal, connects to
cavity 27 of the ABS control module. Circuit B2 con-
nects to cavity 45 of the module and provides the
HIGH signal.
Circuits B4 and B3 provide signals to ABS control
module from the left rear wheel speed sensor. Circuit
B3, which provides the LOW signal, connects to cav-
ity 28 of the ABS control module. Circuit B4 connects
to cavity 46 of the module and provides the HIGH
signal.
ACCELERATION SWITCH
During four-wheel drive operation, the acceleration
switch provides deceleration data to the ABS control
module. Refer to Group 5, Brakes for additional in-
formation.
Circuits B21, B22, and B23 connect the accelera-
tion sensor to the ABS control module. Circuits B21
and B22 provide switch states while circuit B23 pro-
vides ground. At the ABS control module circuit B21
connects to cavity 25, circuit B22 connects to cavity
43 and circuit B23 connects to cavity 26.
ABS POWER RELAY
The ABS power relay is located in the Power Dis-
tribution Center (PDC). When the ABS module
grounds the ABS power relay on circuit B20, the re-
lay switches to connect circuit B15 and circuit A20
from PDC fuse 10. Circuit F15 from fuse 13 in the
fuse block splices to feed the coil side of the ABS
power relay. Circuit B20 connects to cavity 34 of the
ABS control module.
Circuit B15 is double crimped at the ABS power re-
lay. One branch of circuit B15 supplies power to the
coil side of the ABS pump motor relay. The other
branch of circuit B15 splices to cavities 3 and 33 of
the ABS control module and to the hydraulic control
unit.
ABS PUMP MOTOR RELAY
The ABS pump motor relay in the Power Distribu-
tion Center (PDC) supplies voltage to the ABS pump
motor. When the ABS power relay energizes, circuit
B15 supplies battery voltage to the coil side of the
ABS pump motor relay. The ABS control module pro-
vides ground for the relay on circuit B116. Circuit
B116 connects to cavity 15 of the ABS control mod-
ule.
When the ABS pump motor energizes, it connects
circuit A10 from PDC fuse 9 to circuit B25. Circuit
B25 supplies battery voltage to the pump motor. Cir-
cuit Z12 provides ground for the pump motor.
PUMP MOTOR SPEED SENSOR
The input from the pump motor speed sensor tells
the ABS control module that the pump is operating.
Circuit B17 and B16 from the control module connect
to the speed sensor.
BRAKE PEDAL TRAVEL SENSOR
The brake pedal travel sensor provides the ABS
control module with data regarding brake pedal posi-
tion. The sensor is a variable resistor that the ABS
J8W-32 ANTI-LOCK BRAKESÐYJ VEHICLES 8W - 32 - 1

module provides voltage to and receives input from.
Circuit B210 from cavity 41 of the ABS control mod-
ule provides voltage to the sensor. Circuit B258 car-
ries the signal from the sensor to cavity 16 of the
ABS module.
BRAKE SWITCH INPUT
Circuit L50 from the stop lamp provides the brake
switch input to the ABS control module. When the
brake pedal is pressed, the stop lamp switch closes to
supply battery voltage from circuit F32 to circuit
L50. Circuit L50 connects to cavity 32 of the ABS
control module. Circuit F32 originates at fuse 3 in
the fuse block.
Circuit A6 from Power Distribution Center (PDC)
fuse 3 supplies voltage to the fuse block for circuit
F32.
HYDRAULIC CONTROL UNIT
When the ABS power relay energizes, two branches
of circuit B15 splice to supply voltage to the isolation
and decay solenoids in the hydraulic control unit.
The hydraulic control unit contains three separate
isolation solenoids and three separate decay sole-
noids. The ABS control module activates the decay
and isolation solenoids by providing separate ground
paths for each.
The ABS module provides a ground path for the
rear isolation solenoid on circuit B251. Circuit B251
connects to cavity 54 of the ABS control module.
For the right front isolation solenoid, the ABS mod-
ule provides a ground path on circuit B249. Circuit
B249 connects to cavity 38 of the ABS control mod-
ule.
On circuit B245, the ABS module provides ground
for the left front isolation solenoid. Circuit B245 con-
nects to cavity 20 of the ABS control module.
The ABS module provides a ground path for the
rear decay solenoid on circuit B254. Circuit B254
connects to cavity 36 of the ABS control module.
For the right front decay solenoid, the ABS module
provides a ground path on circuit B248. Circuit B248
connects to cavity 21 of the ABS control module.
On circuit B243, the ABS module provides ground
for the left decay solenoid. Circuit B243 connects to
cavity 2 of the ABS control module.
ABS WARNING LAMP
Circuit G5 provides power for the ABS warning
lamp at the instrument cluster. Ground for the ABS
warning lamp is provided by either the ABS control
module or by the ABS power relay when the relay is
not energized. The ABS control module illuminates
the lamp by providing ground on circuit G19.
Circuit G19 splices to connect to circuit B15
through a diode. When the ABS power relay is notenergized, it connects circuit B15 to circuit Z12. The
ground path for the warning lamp is through the di-
ode to circuit B15, through the ABS power relay to
ground on circuit Z12.
The diode between circuit G19 and B15 prevents
voltage from flowing to the ABS control module when
the ABS power relay switches to supply power on cir-
cuit B15.
DATA LINK CONNECTOR
Circuit D11 from cavity 23 of the ABS control mod-
ule receives data from the DRB scan tool through the
data link connector. The ABS control module trans-
mits data to the scan tool through the connector on
circuit D12. Circuit D12 originates at cavity 42 of the
ABS control module.
Through the data link connector, circuit Z12 pro-
vides ground for the DRB scan tool. Circuit Z12 ter-
minates at the right rear of the dash panel.
Circuit A4 from fuse 8 in the Power Distribution
Center (PDC) supplies power to fuse 16 in the PDC.
Fuse 16 powers circuit M1 which supplies battery
voltage to the scan tool through the diagnostic con-
nector.
HELPFUL INFORMATION
²Check fuses 4, 9 and 10 in the PDC
²Check fuse 13 in the fuse block
DIAGRAM INDEX
Component Page
ABS Power Relay........................8W-32-4
ABS Pump Motor/Sensor...................8W-32-5
ABS Warning Lamp.......................8W-32-4
ABS Control Module..................8W-32-3 thru 7
ABS Pump Motor Relay....................8W-32-5
Brake Pedal Travel Sensor...................8W-32-6
Data Link Connector......................8W-32-6
Fuse 1 Fuse Block........................8W-32-4
Fuse 3 Fuse Block........................8W-32-6
Fuse 3 (PDC)...........................8W-32-6
Fuse 4 (PDC)...........................8W-32-4
Fuse 8 (PDC)...........................8W-32-6
Fuse 10 (PDC)..........................8W-32-4
Fuse 12 Fuse Block.......................8W-32-4
Fuse 12 (PDC)..........................8W-32-6
Fuse 13 (PDC)..........................8W-32-4
Hydraulic Actuation Unit....................8W-32-3
Ignition Switch..........................8W-32-4
Powertrain Control Module (PCM)..............8W-32-6
Stop Lamp Switch........................8W-32-6
Wheel Speed Sensors......................8W-32-7
8W - 32 - 2 8W-32 ANTI-LOCK BRAKESÐYJ VEHICLESJ

INSTRUMENT CLUSTER
INSTRUMENT CLUSTER
The instrument cluster contains the gauges and
warning lamps. All gauges have magnetic move-
ments.
When the ignition switch is in either the START or
RUN position, circuit A1 from fuse 4 in the Power
Distribution Center (PDC) connects to circuit A21.
Circuit A21 powers fuse 9 in the fuse block. Fuse 9
powers circuit G5. One branch of circuit G5 connects
directly to the combination buzzer. The other branch
of circuit G5 splices to power the gauges, speedome-
ter, tachometer, voltmeter, indicator lamps, and
warning lamps in the instrument cluster.
When the parking lamps or headlamps are ON, the
headlamp switch connects circuit F33 to circuit L7.
Circuit L7 splices to the dimmer switch. Circuit E1
from the dimmer switch powers fuse 10 in the fuse
block when the parking lamps or headlamps are ON.
Circuit E2 from fuse 10 in the fuse block feeds the
illumination lamps in the instrument cluster.
Circuit Z1 provides ground the instrument cluster
illumination lamps, gauges and warning lamps.
HELPFUL INFORMATION
²Circuit G5 also powers the heated rear window,
A/C compressor clutch relay. On Canadian vehicles,
circuit G5 powers the Daytime Running Lamps
(DRL) module.
²Circuit F33 originates at fuse 8 in the fuse block.
Circuit A6 from fuse 3 in the PDC powers fuse 8 in
the fuse block.
ENGINE COOLANT TEMPERATURE GAUGE
Circuit G20 connects the engine coolant tempera-
ture gauge to the engine coolant temperature sensor.
The sensor is a variable resistor and case grounded
to the engine. Circuit G5 connects to the instrument
cluster and supplies voltage for the gauge.
The gauge uses two coils. The first coil has fixed
current flowing through it to maintain magnetic field
strength. Circuit Z1 provides ground for the fixed
current coil. The current level passing through the
second coil is controlled by the variable resistor in
the engine coolant temperature sender. The changing
current varies the magnetic field in the second coil.
Refer to group 8E, Instrument Panel and Gauges
for gauge operation.
FUEL GAUGE
Circuit G4 connects the fuel level sensor to the fuel
gauge in the instrument cluster. Circuit G5 supplies
voltage to the fuel gauge. The fuel level sensor draws
voltage from circuit G5 through the fuel gauge on cir-
cuit G4.The gauge uses two coils. The first coil has fixed
current flowing through it to maintain magnetic field
strength. Circuit Z1 provides ground for the fixed
current coil. The current level passing through the
second coil is controlled by the variable resistor in
the fuel level sensor. The changing current varies the
magnetic field in the second coil.
Circuit Z2 provides the ground path for the fuel
level sensor.
Refer to group 8E, Instrument Panel and Gauges
for gauge operation.
OIL PRESSURE GAUGE
The case grounded oil pressure sending unit is a
variable resistor. The sending unit connects to the oil
pressure gauge on circuit G60.
Circuit G5 connects to the instrument cluster and
supplies battery voltage to the oil pressure gauge.
The gauge uses two coils. The first coil has fixed cur-
rent flowing through it to maintain magnetic field
strength. Circuit Z1 provides ground for the fixed
current coil. The current level passing through the
second coil is controlled by the variable resistor in
the oil pressure sending unit. The changing current
varies the magnetic field in the second coil.
Refer to group 8E, Instrument Panel and Gauges
for gauge operation.
TACHOMETER
The Powertrain Control Module (PCM) provides
the tachometer signal to the electronic tachometer on
circuit G21. Circuit G21 originates at cavity 43 of the
PCM. Circuit Z1 provides ground for the tachometer's
internal logic circuits.
SPEEDOMETER
The electronic speedometer and odometer receive a
signal from the vehicle speed sensor on circuit G7.
Circuit G5 connects to the instrument cluster and
supplies battery voltage to the speedometer. Circuit
Z1 provides ground for the speedometer internal logic
circuits.
Circuit G7 splices to connect to the Powertrain
Control Module (PCM) and if equipped, the Daytime
Running Lamps (DRL) module.
FOUR-WHEEL DRIVE (4WD) INDICATOR LAMP
When the 4WD switch closes, circuit Z1 provides
ground for the 4WD indicator lamp in the instrument
panel. Circuit G5 connects to the instrument cluster
and supplies battery voltage to the 4WD indicator
lamp. Circuit G1 connects the indicator lamp to the
4WD switch.
J8W-40 INSTRUMENT CLUSTERÐYJ VEHICLES 8W - 40 - 1

MALFUNCTION INDICATOR (CHECK ENGINE)
LAMP
The Powertrain Control Module (PCM) provides
ground for the malfunction indicator (Check Engine)
lamp on circuit G3. Circuit G3 connects to cavity 32
of the PCM. Circuit G5 connects to the instrument
cluster and supplies battery voltage for the malfunc-
tion indicator lamp. When illuminated, the malfunc-
tion indicator lamp displays the message CHECK
ENGINE.
For information regarding diagnostic trouble code
access using the malfunction indicator lamp, refer to
Group 14, Fuel Systems.
UP-SHIFT LAMP
On vehicles equipped with a manual transmission,
the Powertrain Control Module (PCM) provides
ground for the Up-Shift lamp on circuit K54. Circuit
G5 provides battery voltage for the lamp.
ABS WARNING LAMP
Circuit G5 provides power for the ABS warning
lamp at the instrument cluster. Ground for the ABS
warning lamp is provided by either the ABS control
module or by the ABS power relay when the relay is
not energized. The ABS control module illuminates
the lamp by providing ground on circuit G19.
Circuit G19 splices to connect to circuit B15
through a diode. When the ABS power relay is not
energized, it connects circuit B15 to circuit Z12. The
ground path for the warning lamp is provided
through the diode to circuit B15, through the ABS
power relay to ground on circuit Z12.
The diode between circuit G19 and B15 prevents
voltage from flowing to the ABS control module when
the ABS power relay switches to supply power on cir-
cuit B15.
BRAKE WARNING LAMP
Circuit G5 provides battery voltage for the brake
warning lamp. Circuit G11 can provide ground for
the lamp in 3 ways. The first ground path is through
the ignition switch when the key is in the START po-
sition.
The second ground path for the brake warning
lamp on circuit G11 is through the case grounded
brake warning switch. When the switch closes it pro-
vides a ground.
The third ground path on circuit G11 is through
the case grounded park brake switch. When the
switch closes it provides ground.
HIGH BEAM INDICATOR LAMP
Circuit G34 supplies power for the high-beam indi-
cator lamp when the operator either flashes the opti-
cal horn (high beams) or selects high beam operation.
Circuit Z1 provides the ground path for the lamp.
Circuit L3 from the headlamp switch powers the
high beam circuits of the headlamps. On vehicles not
equipped with Daytime Running Lamps (DRL), cir-
cuit G34 double crimps to circuit L3 at the bulkhead
connector.
On vehicles equipped with DRL, circuit L3 splices
to the DRL module. The DRL module powers circuit
G34.
TURN SIGNAL INDICATOR LAMPS
Circuit L61 supplies battery voltage to the left turn
signal indicator lamp. The right turn signal indicator
lamp receives battery voltage from circuit L60. The
turn signal/hazard flasher switch powers circuits L60
and L61. Circuit Z1 provides ground for the lamps.
HELPFUL INFORMATION
²If the warning lamps, gauges and indicator lamps
don't operate, check fuse 4 in the PDC and fuse 9 in
the fuse block.
²If the illumination lamps don't operate, check fuse
10 in the fuse block.
DIAGRAM INDEX
Component Page
4WD Switch............................8W-40-9
ABS Control Module......................8W-40-5
Brake Warning Switch.....................8W-40-5
Combination Buzzer.....................8W-40-7, 8
Daytime Running Lamp (DRL) Module.........8W-40-4, 6
Engine Coolant Temperature Sensor...........8W-40-7, 8
Engine Oil Pressure Sensor..................8W-40-9
Fuse 3 (PDC).......................8W-40-3, 7, 8
Fuse 4 (PDC).......................8W-40-4, 7, 8
Fuse 7 (PDC)...........................8W-40-6
Fuse 8 (Fuse Block)...................8W-40-3, 7, 8
Fuse 9 (Fuse Block).......................8W-40-8
Fuse 10 (Fuse Block).................8W-40-3, 7, 10
Gauge Package......................8W-40-7, 8, 9
Headlamp Switch...................8W-40-3, 6, 7, 8
Headlamp Dimmer Switch...................8W-40-6
Ignition Switch......................8W-40-4, 5, 8
Instrument Cluster...................8W-40-3 thru 9
Panel Lamp Dimmer Switch..............8W-40-3, 7, 8
Park Brake Switch........................8W-40-5
Powertrain Control Module.................8W-40-4, 5
8W - 40 - 2 8W-40 INSTRUMENT CLUSTERÐYJ VEHICLESJ

HORN/CIGAR LIGHTER
HORN
The horn system uses a switch and horn relay. The
horn switch is in the center of the steering wheel.
Circuit A4 from fuse 8 in the Power Distribution
Center (PDC) feeds circuit F31 through fuse 15 in
the PDC. Circuit F31 is HOT at all times and powers
the coil and contact sides of the horn relay.
When the case grounded horn switch is pressed,
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 horn. Circuit Z1
provides ground for the horn.
HELPFUL INFORMATION
²The horn switch is grounded to the steering wheel.
²Circuit F31 is double crimped at the coil side of
the horn relay.
²Check fuse 8 in the PDC and fuse 15 in the fuse
block.
CIGAR LIGHTER
In the ACCESSORY or RUN position, the ignition
switch supplies voltage to fuse 7 in the fuse block on
circuit A31. Fuse 7 feeds circuit F30 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 4 in the PDC
with circuit A31.
²Circuit F30 also powers the radio and radio relay.
DIAGRAM INDEX
Component Page
Cigar Lighter...........................8W-41-3
Fuse 4 (PDC)...........................8W-41-3
Fuse 8 (PDC)...........................8W-41-2
Fuse 11 (PDC)..........................8W-41-2
Fuse 7 (Fuse Block).......................8W-41-3
Horn.................................8W-41-2
Horn Relay.............................8W-41-2
Horn Switch............................8W-41-2
Ignition Switch..........................8W-41-3
J8W-41 HORN/CIGAR LIGHTERÐYJ VEHICLES 8W - 41 - 1

AIR CONDITIONING/HEATER
CONTENTS
page page
HEATER AND AIR CONDITIONING........... 2 HEATERSYSTEM......................... 1
GENERAL INFORMATION
This section of the wiring diagrams is divided into
two sub-sections; Heater, and A/C-Heater. When re-
ferring to the circuit descriptions or wiring diagrams,
ensure that you use the correct sub-section.
HEATER SYSTEM
HEATER
In the RUN position, the ignition switch connects
circuit A1 from fuse 4 in the Power Distribution Cen-
ter (PDC) to circuit A22. Circuit A22 powers a bus
bar in the fuse block that supplies voltage to circuit
C1 through fuse 12.
A heater-off switch in circuit C1 opens when the
heater controls are in the VENT position. When the
heater-off switch closes, circuit C1 supplies battery
voltage to the blower motor switch. The switch sets
blower motor speed to HIGH, MEDIUM, LOW or
OFF.
The switch connects to the blower motor resistor
block in the LOW and MEDIUM positions and di-
rectly to the blower motor in the HIGH position. The
resistor block contains two resistors connected in se-
ries. Circuit C7 connects the resistor block to the
blower motor.
From the blower motor resistor block, circuit C7 is
double crimped at the HIGH terminal of the blower
motor switch. Circuit C7 continues to the blower mo-
tor from the blower motor switch.
When the blower motor switch is in the LOW posi-
tion, it supplies voltage to the resistor block on cir-
cuit C4. From circuit C4, voltage passes through both
resistors in the resistor block to the blower motor on
circuit C7.In the MEDIUM position, the blower motor sup-
plies voltage to the resistor block on circuit C5. From
circuit C5 voltage flows through one resistor to the
blower motor on circuit C7.
In the HIGH position, the blower motor switch con-
nects directly to the blower motor on circuit C7. Volt-
age does not pass through the resistor block.
Circuit Z1 provides ground for the blower motor.
HELPFUL INFORMATION
²Check fuse 4 in the PDC.
²Check fuse 12 in the fuse block.
DIAGRAM INDEX
Component Page
Blower Motor...........................8W-42-3
Blower Motor Resistor.....................8W-42-3
Blower Motor Switch......................8W-42-3
Fuse 4 (PDC)...........................8W-42-3
Fuse 12 (Fuse Block)......................8W-42-3
Heater Switch...........................8W-42-3
Ignition Switch..........................8W-42-3
J8W-42 AIR CONDITIONING/HEATERÐYJ VEHICLES 8W - 42 - 1