train Control Module (PCM) with an input signal
(voltage). The signal represents throttle blade posi-
tion. As the position of the throttle blade changes,
the resistance of the TPS changes.
The PCM supplies approximately 5 volts to the
TPS. The TPS output voltage (input signal to the
powertrain control module) represents throttle blade
position. The TPS output voltage to the PCM varies
from approximately 0.38 volts to 1.2 volts at mini-
mum throttle opening (idle) to a maximum of 3.1
volts to 4.4 volts at wide open throttle.
Along with inputs from other sensors, the PCM
uses the TPS input to determine current engine oper-
ating conditions. The PCM also adjusts fuel injector
pulse width and ignition timing based on these
inputs.
IGNITION SWITCH
In the RUN position, the ignition switch connects
power from the Power Distribution Center (PDC) to a
30 amp fuse in the fuse block, back to a bus bar in
the PDC. The bus bar feeds circuits for the Power-
train Control Module (PCM), duty cycle purge sole-
noid, EGR solenoid, and ABS system. The bus bar in
the PDC feeds the coil side of the radiator fan relay,
A/C compressor clutch relay, and the fuel pump relay.
It also feeds the Airbag Control Module (ACM)
LOCK KEY CYLINDER
The lock cylinder is inserted in the end of the
housing opposite the ignition switch. The ignition key
rotates the cylinder to 5 different detents (Fig. 16):
²Accessory
²Off (lock)
²Unlock
²On/Run
²Start
IGNITION INTERLOCK
All vehicles equipped with automatic transaxles
have an interlock system. The system prevents shift-
ing the vehicle out of Park unless the ignition lock
cylinder is in the Off, Run or Start position. In addi-
tion, the operator cannot rotate the key to the lock
position unless the shifter is in the park position. On
vehicles equipped with floor shift refer to Group 21 -
Transaxle for Automatic Transmission Shifter/Igni-
tion Interlock.
DIAGNOSIS AND TESTING
TESTING FOR SPARK AT COILÐ2.0/2.4L
WARNING: THE DIRECT IGNITION SYSTEMS GEN-
ERATES APPROXIMATELY 40,000 VOLTS. PER-
SONAL INJURY COULD RESULT FROM CONTACT
WITH THIS SYSTEM.
The coil pack contains independent coils. Each coil
must be checked individually.
CAUTION: Spark plug wire damage may occur if
the spark plug is moved more than 1/4 inch away
from the engine ground.
CAUTION: Do not leave any one spark plug cable
disconnected any longer than 30 seconds or possi-
ble heat damage to catalytic converter will occur.
CAUTION: Test must be performed at idle and in
park only with the parking brake on.
NOTE: New isolated engine valve cover may not
provide adequate ground. Use engine block as
engine ground.
Fig. 15 MAP/IAT sensorÐDOHCFig. 16 Ignition Lock Cylinder Detents
PLIGNITION SYSTEM 8D - 7
DESCRIPTION AND OPERATION (Continued)
INSTRUMENT PANEL AND SYSTEMS
CONTENTS
page page
GENERAL INFORMATION
INTRODUCTION......................... 1
DESCRIPTION AND OPERATION
DOME LAMP............................ 1
ELECTRONIC DIGITAL CLOCK.............. 1
INSTRUMENT CLUSTER................... 2
WARNING AND INDICATOR LAMPS......... 2
DIAGNOSIS AND TESTING
AIRBAG WARNING SYSTEM............... 2
BRAKE SYSTEM WARNING LAMP TEST...... 2
FOG LAMP SWITCH TEST................. 2
FUEL TANK SENDING UNIT TEST........... 3
HEADLAMP SWITCH TEST................. 3
HEATER A/C BLOWER SWITCH TEST........ 3
HEATER BLOWER SWITCH TEST............ 3
INDIVIDUAL GAUGE INOPERATIVE.......... 4
INSTRUMENT PANEL AND COMPONENTS.... 4
LOW OIL PRESSURE WARNING LAMP TEST . . 4
MULTIPLE GAUGE INOPERATIVE TEST....... 4
SEAT BELT REMINDER SYSTEM TEST....... 6
SENDING UNIT......................... 6
SERVICE ENGINE SOON INDICATOR......... 6
VEHICLE SPEED SENSOR TEST............. 6
REMOVAL AND INSTALLATION
ASH RECEIVER RETAINER AND LAMP....... 6
CENTER BEZEL.......................... 6
CIGAR LIGHTER RECEPTACLE.............. 6
CLUSTER LAMP......................... 7
CLUSTER PRINTED CIRCUIT BOARD........ 7CLUSTER.............................. 7
DOME LENS/LAMP....................... 8
FLOOR CONSOLE........................ 8
GAUGE................................ 8
GLOVE BOX DOOR/BIN................... 8
GLOVE BOX SWITCH/LAMP................ 9
HEADLAMP SWITCH..................... 9
HEATER A/C CONTROL BLOWER SWITCH . . . 10
HEATER A/C CONTROL LAMP............ 10
HEATER A/C CONTROL................... 9
HEATER CONTROL BLOWER SWITCH....... 10
IGNITION KEY LAMP.................... 10
INSTRUMENT PANEL.................... 10
LEFT TRIM PANEL...................... 10
ODOMETER............................ 10
RADIO................................ 12
REAR WINDOW DEFOGGER AND/OR FOG
LAMP SWITCH....................... 12
RIGHT TRIM PANEL..................... 12
SHIFTER KNOB......................... 13
STEERING COLUMN COVER LINER......... 13
STEERING COLUMN COVER.............. 13
STEERING COLUMN SHROUDS............ 13
TOP COVER AND CLUSTER BEZEL
REMOVAL........................... 14
TRANSMISSION RANGE INDICATOR LAMP . . 14
TRUNK LAMP/LENS..................... 14
VEHICLE SPEED SENSOR................ 14
GENERAL INFORMATION
INTRODUCTION
The purpose of the dash gauges and indicator
lamps is to keep the driver informed about the oper-
ating condition of the vehicle. If an abnormal condi-
tion occurs, the driver is informed by indicator lamp.
The driver can seek service before damage occurs.
Indicator lamps use ON/OFF switch functions for
operation, while gauges use a sending unit or sensor.
DESCRIPTION AND OPERATION
DOME LAMP
The Dome Lamp operates when a door is open or
when the headlamp switch is placed in courtesy posi-
tion.
ELECTRONIC DIGITAL CLOCK
The electronic digital clock is in the radio. The
clock and radio each use the display panel built into
the radio. A digital readout indicates the time in
hours and minutes whenever the ignition switch is in
the ON or ACC position.
PLINSTRUMENT PANEL AND SYSTEMS 8E - 1
When the ignition switch is in the OFF position, or
when the radio frequency is being displayed, time
keeping is accurately maintained.
The procedure for setting the clock varies slightly
with each radio. The correct procedure is described in
the individual radio operating instructions. Refer to
the Owner's Manual supplied with the vehicle.
INSTRUMENT CLUSTER
There are two conventional instrument cluster
assemblies available. The clusters electronically drive
the speedometer, odometer, and gauges (Fig. 1) and
(Fig. 2).
GAUGES
All gauges in the electronic clusters are the analog
type gauges. When the ignition switch is moved to
the OFF position, the cluster drives each gauge to its
lowest position.
WARNING AND INDICATOR LAMPS
The instrument cluster has warning lamps and
indicators for the following systems:
²Airbag
²Anti-lock Brakes (ABS) if equipped
²Brake warning
²Charging System
²Door Ajar
²High beam indicator
²Low oil pressure
²Malfunction indicator (service engine soon) lamp
²Right and left turn signals.
²Seat belt warning
DIAGNOSIS AND TESTING
AIRBAG WARNING SYSTEM
For testing of this system refer to Group 8M,
Restraint Systems.
BRAKE SYSTEM WARNING LAMP TEST
The brake warning lamp illuminates when the
parking brake is applied with ignition switch turned
to the ON position. The same lamp will also illumi-
nate if one of the two service brake systems fail the
when brake pedal is applied.
To test the system:
²As the ignition switch is turned to the start posi-
tion the lamp should light.
²Turn ignition switch to the ON position and
apply the parking brake. The lamp should light.
If lamp fails to light inspect for:
²A burned out lamp
²Loose, corroded or damaged socket
²A damaged circuit board
²A broken or disconnected wire at the switch
²Defective switch
To test the service brake warning system, refer to
Group 5, Brakes, Hydraulic System Control Valves.
FOG LAMP SWITCH TEST
(1) Remove the fog lamp switch. Refer to the Rear
Window Defogger and/or Fog Lamp Switch Removal.
(2) Using two jumper wires, connect Pin 2 and Pin
4 of the switch to battery voltage.
(3) Using a test lamp, connect the test lamp to Pin
3 as shown in (Fig. 3). Refer to (Fig. 4) for fog lamp
switch circuit.
(4) Push the fog lamp switch button. The test lamp
and the LED indicator on the front of the switch
should illuminate.
(5) If either the LED or the test lamp fails to illu-
minate, replace the switch.Fig. 1 Instrument Cluster Without Tachometer
Fig. 2 Instrument Cluster With Tachometer
Fig. 3 Fog Lamp Switch Test
8E - 2 INSTRUMENT PANEL AND SYSTEMSPL
DESCRIPTION AND OPERATION (Continued)
HORNS
CONTENTS
page page
DESCRIPTION AND OPERATION
INTRODUCTION......................... 1
DIAGNOSIS AND TESTING
HORN RELAY........................... 2
HORN SWITCH.......................... 2
HORN................................. 1SYSTEM TEST.......................... 2
REMOVAL AND INSTALLATION
HORN RELAY........................... 4
HORN SWITCHES........................ 4
HORN................................. 4
DESCRIPTION AND OPERATION
INTRODUCTION
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAG, SEE GROUP 8M, RESTRAINT SYSTEMS FOR
STEERING WHEEL OR COLUMN REMOVAL PROCE-
DURES.
The horn circuit consists of a horn switch, horn
relay, and horn. The horn circuit feed is from the fuse
to the horn relay in the Power Distribution Center
(PDC). The PDC is mounted on the battery tray.
When the horn switch is depressed, it completes the
ground circuit. The horn relay coil closes contacts
and allows current to flow to the horn. The horn is
grounded to the headlamp ground connection (Fig. 1)
.
HORN SWITCH
The horn switch is mounted between the outer and
inner cover of the Driver Airbag Module (Fig. 2).
When the Driver Airbag is pressed the horn switch
makes contact to ground. The ground signal is car-
ried to the horn relay and the horn sounds.
(1) The horn switch grounds to the airbag housing.(2) If horn does not sound check for corrosion:
²Horn wire
²Horn switch ground connected to airbag metal
housing
²Airbag to steering wheel
²Ensure horn wire is properly connected and
insulator is in place on wire
(3) Refer to Group 8W, Wiring Diagrams if wire
circuit needs to be repaired.
DIAGNOSIS AND TESTING
HORN
(1) Disconnect wire connector at horn.
(2) Using a voltmeter, connect one lead to ground
terminal and the other lead to the positive wire ter-
minal (Fig. 3).
(3) Depress the horn switch, battery voltage
should be present.
(4) If no voltage, refer to Horn System Test. If volt-
age is OK, go to Step 5.
Fig. 1 Horn System
Fig. 2 Horn Switch
PLHORNS 8G - 1
(5) Using ohmmeter, test ground wire for continu-
ity to ground.
(6) If no ground repair as necessary.
(7) If wires test OK and horn does not sound,
replace horn.
HORN RELAY
(1) Remove horn relay.
(2) Using ohmmeter, test for continuity between
ground and circuit 65 of horn relay.
(a) When the horn switch is not depressed, no
continuity should be present.
(b) Continuity to ground when horn switch is
depressed.
(c) If continuity is not correct repair horn switch
or wiring as necessary, refer to Group 8W, Wiring
Diagrams.
(3) Insert a jumper wire between circuit 63 and 66
of the Power Distribution Center.
(a) If horn sounds replace relay.
(b) If the horn does not sound, install horn relay
and refer to Horn Test.
(4) Using voltmeter, test voltage at:
(a) Circuit 62 and 66 test for battery voltage
from fuse C to body ground.
(b) If voltage is incorrect repair as necessary.
Refer to Group 8W, Wiring Diagrams.
(5) Check relay for 70 to 75 ohms resistance from
terminal 85 to 86 (Fig. 4). If resistance not OK,
replace relay.
HORN SWITCH
(1) Remove horn relay from the Power Distribution
Center.
(2) Using ohmmeter, connect one lead to ground
and the other lead to cavity 65 of the power distribu-
tion center (Fig. 5).
(3) Depress horn switch, should have continuity. If
no continuity go to Step 4.(4) Test continuity at horn switch, remove the
Driver Airbag Module. Refer to Driver Airbag Module
Removal and Installation procedures.
(5) Using ohmmeter, connect one lead to the air-
bag module ground and the other lead to B+ wire
(Fig. 6).
(6) Depress horn switch, and the meter should
show continuity. If no continuity, replace the Driver
Airbag Module. If OK, repair as necessary.
SYSTEM TEST
Refer to Horn System Test Table. If the horn does
not sound, check horn fuse located in the Power Dis-
tribution Center. If the fuse is blown, replace with
Fig. 3 Horn and Connector
Fig. 4 Horn and Connector
Fig. 5 Power Distribution Center
Fig. 6 Test Horn Switch - Driver Airbag Module
8G - 2 HORNSPL
DIAGNOSIS AND TESTING (Continued)
the correct fuse. If the horn fail to sound and the
new fuse blows when depressing the horn switch, a
short circuit in the horn or the horn wiring between
the fuse terminal and the horn is responsible, or a
defective horn switch allowed the horn to burn out is
responsible.
If the fuse is OK, test horn relay refer to Horn
Relay Test.
If the relay is OK, test horn refer to Horn Test.CAUTION: Continuous sounding of horn may
cause horn relay to fail.
Should the horn sound continuously:
²Unplug the horn relay from Power Distribution
Center.
²Refer to Horn Relay Test.
Refer to Group 8W, wiring Disgrams for circuit and
wiring information.
HORN SYSTEM TEST
CONDITION POSSIBLE CAUSE CORRECTION
Horn sounds continuously.
NOTE: Immediately unplug
horn relay in the Power
Distribution Center (PDC)(1) Faulty horn relay.
(2) Horn control circuit to relay
shorted to ground.
(3) Pinched horn switch wire under
Driver Airbag Module.
(4) Defective horn switch(1) Refer to horn relay test.
(2) Check terminal 65 in PDC for
continuity to ground. If continuity to ground
indicates:
(a) Steering Wheel horn switch/lead
shorted to ground.
(b) Wiring harness shorted to ground. Find
the short and repair as necessary.
(3) Replace Driver Airbag Module.
(4) Replace Driver Airbag Module.
Horn sound intermittently as
the steering wheel is turned.(1) Horn relay control circuit X3 is
shorted to ground inside steering
wheel.
(2) Pinched horn switch wire under
Driver Airbag Module
(3) Defective horn switch(1) Remove Driver Airbag Module and/or
steering wheel. Check for rubbing or loose
wire/connector, repair as necessary.
(2) Replace Driver Airbag Module.
(3) Replace Driver Airbag Module.
Horn does not sound (1) Check fuse 23 in PDC
(2) No Voltage at horn RELAY
TERMINALS 62 & 66, and fuse is
OK.
(3) Open circuit from terminal 65 of
the horn relay to horn switch X3
circuit.
(4) Defective or damaged horn.
(5) Defective horn switch(1) Replace fuse if blown repair as
necessary.
(2) No voltage, repair PDC as necessary.
(3) Repair circuit as necessary.
(4) Voltage at horn when horn switch is
pressed, replace horn.
(5) Replace Driver Airbag Module.
Fuse blows when horn
sounds(1) Short circuit in horn or horn
wiring(1) Remove horn relay, check for shorted
horn or horn wiring. Disconnect horn wire
harness to isolate short and repair as
necessary.
Fuse blows without blowing
horn(1) Short circuit (1) Remove relay, install new fuse, if fuse
does not blow replace horn relay. If fuse
blows with relay removed, check for short
to ground with ohmmeter on circuit
between terminals 62 & 66 and the fuse
terminal. Repair as necessary.
NOTE: For wiring repairs
refer to Group 8W, Wire
Diagrams.
PLHORNS 8G - 3
DIAGNOSIS AND TESTING (Continued)
REMOVAL AND INSTALLATION
HORN
REMOVAL
Disconnect connector and remove horn attaching
nuts from the bumper support bracket (Fig. 7).
INSTALLATION
For installation, reverse the above procedures.
Insure that the horn projector does not touch bumper
reinforcement or the sound output may be altered.
HORN RELAY
REMOVAL
(1) Remove the Power Distribution Center cover
and locate the horn relay.
(2) Remove the horn relay (Fig. 5).
INSTALLATION
For installation, reverse the above procedures.
HORN SWITCHES
The Horn Switch is part of the Driver Airbag Mod-
ule. Refer to Driver Airbag Module Removal and
Installation procedures in Group 8M.
Fig. 7 Horn Location
8G - 4 HORNSPL
VEHICLE SPEED CONTROL SYSTEM
CONTENTS
page page
GENERAL INFORMATION
INTRODUCTION......................... 1
DESCRIPTION AND OPERATION
POWERTRAIN CONTROL MODULE.......... 3
SERVO CABLE.......................... 3
SPEED CONTROL SERVO.................. 1
SPEED CONTROL SWITCHES.............. 2
STOP LAMP SWITCH..................... 3
VACUUM RESERVOIR.................... 3
VEHICLE SPEED AND DISTANCE............ 3
DIAGNOSIS AND TESTING
CHECKING FOR DIAGNOSTIC CODES........ 4
ELECTRICAL TESTS AT POWERTRAIN
CONTROL MODULE..................... 7
OVERSHOOT/UNDERSHOOT FOLLOWING
SPEED CONTROL SET................... 6ROAD TEST............................ 3
SERVO VACUUM TEST.................... 6
SPEED CONTROL ELECTRICAL TEST........ 4
SPEED CONTROL SWITCH TEST............ 6
STOP LAMP SWITCH TEST................ 6
VACUUM SUPPLY TEST................... 8
VEHICLE SPEED SENSOR................. 8
REMOVAL AND INSTALLATION
POWERTRAIN CONTROL MODULE......... 10
SPEED CONTROL SERVO CABLE............ 9
SPEED CONTROL SERVO.................. 8
SPEED CONTROL SWITCH................. 8
STOP LAMP SWITCH.................... 8
VACUUM RESERVOIR................... 10
VEHICLE SPEED SENSOR................ 10
GENERAL INFORMATION
INTRODUCTION
The speed control system is electronically con-
trolled and vacuum operated. The electronic control
is integrated into the powertrain control module
which is located in the engine compartment. The con-
trols are located on the steering wheel and consist of
five switches. The ON, OFF, and SET buttons are
located on the left side of the airbag module. The
RESUME/ACCEL, CANCEL and COAST buttons are
located on the right side of the airbag module (Fig.
1). For identification and location of the major com-
ponents (Fig. 2) and (Fig. 3).
The system is designed to operate at speeds above
30 mph (50 km/h).
WARNING: THE USE OF SPEED CONTROL IS NOT
RECOMMENDED WHEN DRIVING CONDITIONS DO NOT
PERMIT MAINTAINING A CONSTANT SPEED, SUCH AS
IN HEAVY TRAFFIC OR ON ROADS THAT ARE WIND-
ING, ICY, SNOW COVERED, OR SLIPPERY.
DESCRIPTION AND OPERATION
SPEED CONTROL SERVO
The servo unit consists of a solenoid valve body,
and a vacuum chamber. The PCM controls the sole-noid valve body. The solenoid valve body controls the
application and release of vacuum to the diaphragm
of the vacuum servo. The servo unit cannot be
repaired and is serviced only as a complete assembly.
Fig. 1 Speed Control Switch
PLVEHICLE SPEED CONTROL SYSTEM 8H - 1