1993 CHEVROLET PLYMOUTH ACCLAIM lights

(3) Inspect the spark plug condition. Refer to Spark
Plug Condition in this section.
SPARK PLUG GAP ADJUSTMENT
Check the spark plug gap with a gap gauge. If the
gap is not correct, adjust it by bending the ground
electrode (Fig. 6).
SPARK PLUG INSTALLATION
(1) Start the spark plug into the cylinder head by
hand to avoid cross threading. (2) Tighten spark plugs to 28 N Im (20 ft. lbs.)
torque. (3) Install spark plug cables over spark plugs.
IDLE RPM TESTÐ2.5L AND 3.0L ENGINES
WARNING: APPLY PARKING BRAKE AND/OR BLOCK
WHEELS BEFORE PERFORMING IDLE CHECK OR
ADJUSTMENT, OR ANY TESTS WITH A RUNNING
ENGINE.
Engine idle set rpmshould be recorded when the
vehicle is first brought into shop for testing. This
will assist in diagnosing complaints of engine stalling,
creeping and hard shifting on vehicles equipped with
automatic transaxles. Proceed to the Throttle Body Minimum Airflow pro-
cedures in Group 14.
IGNITION TIMING PROCEDUREÐ2.2L TBI, 2.5L
TBI, 2.5L MPI, AND 3.0L ENGINES
WARNING: APPLY PARKING BRAKE AND/OR BLOCK
WHEELS BEFORE PERFORMING SETTING IGNITION
TIMING OR PERFORMING ANY TEST ON AN OPER-
ATING ENGINE.
Proper ignition timing is required to obtain optimum
engine performance. The distributor must be correctly
indexed to provide correct initial ignition timing. (1) Set the gearshift selector in park or neutral and
apply the parking brake. All lights and accessories
must be off. (2) If using a magnetic timing light, insert the
pickup probe into the open receptacle next to the
timing scale window. If a magnetic timing unit is not
available, use a conventional timing light connected to
the number one cylinder spark plug cable. Do not puncture cables, boots or nipples with
test probes. Always use proper adapters. Punc-
turing the spark plug cables with a probe will
damage the cables. The probe can separate the
conductor and cause high resistance. In addition
breaking the rubber insulation may permit sec-
ondary current to arc to ground. (3) Turn selector switch to the appropriate cylinder
position. (4) Start engine and run until operating tempera-
ture is obtained. (5) With the engine at normal operating tempera-
ture, connect the DRBII scan tool to the data link
connector (diagnostic connector). Access the State Dis-
play screen. Refer to the appropriate Powertrain Diag-
nostics Procedures Manual. If not using the DRBII
scan tool, disconnect the coolant temperature
sensor electrical connector. The electric radiator
fan will operate and the malfunction indicator lamp
(instrument panel Check Engine light) will turn on
after disconnecting the coolant sensor or starting the
DRBII scan tool procedure. (6) Aim Timing Light at timing scale (Fig. 7 or Fig.
8) or read magnetic timing unit. If flash occurs when
timing mark is before specified degree mark, timing is
advanced. To adjust, turn distributor housing in direc-
tion of rotor rotation. If flash occurs when timing mark is after specified
degree mark, timing is retarded. To adjust, turn dis-
tributor housing against direction of rotor rotation.
Refer to Vehicle Emission Control Information label for
correct timing specification. If timing is within 62É of
value specified on the label, proceed to step (8). If
outside specified tolerance, proceed to next step. (7) Loosen distributor hold-down arm screw
enough to rotate the distributor housing (Fig. 9 or
Fig. 6 Setting Spark Plug GapÐTypical
8D - 16 IGNITION SYSTEMS Ä

shield washer fluid, door ajar for each door, and
trunk ajar. It also includes headlamp out, tail lamp
out, and brake lamp out warning lights (Fig. 3),
these lights are operated by a lamp outage module.
When there is no message center there is no door
ajar function.
TRAVELER
The traveler is a five function trip computer. It
uses vacuum fluorescent displays to display: trip
miles, instantaneous fuel economy, trip elapsed time,
trip average fuel economy and, estimate distance to
empty. It is located in the message center (Fig. 4).
WARNING LAMPS AND INDICATOR LIGHTS
The mechanical instrument cluster assemblies
have warning lamps and indicator lights for ten dif-
ferent systems. These include left and right turn sig-
nals, low fuel level, low oil pressure, high beam indicator, seat belt reminder, brake system, malfunc-
tion indicator (check engine) lamp, check gauges, an-
ti-lock system and air bag system indicator. The low oil pressure indicator replaces the Check
Gauges indicator in the cluster assembly without a
tachometer. In the cluster assembly with tachometer, Check
Gauges indictor illuminates in a warning situation.
This will notify driver to check for a problem in cool-
ant temperature, oil pressure or electrical systems.
CLUSTER AND GAUGE SERVICE AND TESTING
CAUTION: Disconnect battery cable. Before servic-
ing the instrument panel. Reconnect battery cable
when power is required for test purposes.
FUEL GAUGEÐFLEXIBLE FUEL
The flexible fuel vehicle uses a dampened fuel
gauge. Methanol fuel causes erratic gauge movement
if the proper gauge is not used. The unique fuel gauge may be identified by either
a green logo on the face of the gauge or by checking
the part number. Remove cluster from the instru-
ment panel and check the part number on top of the
cluster. Refer to Mechanical/Electronic Cluster Re-
moval for proper procedures. Refer to parts catalog
for proper part number.
Fig. 3 Message Center
Fig. 4 Traveler and Message Center
8E - 2 INSTRUMENT PANEL AND GAUGES Ä

disconnected wire at switch. The lamp also lights
when the ignition switch is turned to START.To test service brake warning system, raise vehicle
on a hoist and open a wheel cylinder bleeder while a helper depresses brake pedal and observes warning
lamp. If lamp fails to light, inspect for a burned out
lamp, disconnected socket, a broken or disconnected
wire at switch. If lamp is not burned out and wire continuity is
proven, replace brake warning switch in brake line
Tee fitting mounted on frame rail in engine compart-
ment below master cylinder (Fig. 8 and 9).
CAUTION: If wheel cylinder bleeder was opened
check master cylinder fluid level.
SEAT BELT WARNING SYSTEM
For testing of this system refer to Group 8M, Re-
straint Systems.
MALFUNCTION INDICATOR (CHECK ENGINE) SYSTEM
For testing this system refer to the Powertrain Di-
agnostic Test Procedures booklet.
AIR BAG WARNING SYSTEM
For testing this system refer to Group 8M, Re-
straint Systems.
Fig. 8 Brake Warning Lamp Switch
Fig. 9 Brake System Warning Lamp Diagnosis
8E - 4 INSTRUMENT PANEL AND GAUGES Ä

off, there should be continuity in the system. Start
the engine. With the engine running, the ohmmeter
should show no continuity. If the above results are
not obtained, replace the switch.
BRAKE SYSTEM WARNING LAMP
The brake warning lamp illuminates when parking
brake is applied with ignition key turned ON. The
same lamp will also illuminate should one of the two
service brake systems fail when brake pedal is ap-
plied. To test system turn ignition key ON, and ap-
ply parking brake. If lamp fails to light, inspect for a
burned out lamp, disconnected socket, a broken or
disconnected wire at switch. The lamp also lights
when the ignition switch is turned to START. To test service brake warning system, raise vehicle
on a hoist and open a wheel cylinder bleeder while a
helper depresses brake pedal and observes warning
light. If lamp fails to light, inspect for a burned out
lamp, disconnected socket, a broken or disconnected
wire at switch. If lamp is not burned out and wire continuity is
proven, replace brake warning switch in brake line
Tee fitting mounted on frame rail in engine compart-
ment below master cylinder (Fig.6 and 7). CAUTION: If wheel cylinder bleeder was opened
check master cylinder fluid level.
SEAT BELT WARNING LAMP
For testing of this system, refer to Group 8M, Re-
straint System.
MALFUNCTION INDICATOR (CHECK ENGINE) LAMP
For testing of this system, refer to the Powertrain
Diagnostic Test Procedure Manual.
MECHANICAL/ELECTRONIC CLUSTER REMOVAL
CLUSTER BEZELS REMOVAL
(1) Move gear selector to the low position.
(2) Remove five screws attaching upper bezel to in-
strument panel (Fig. 8). (3) Lift cluster bezel over steering wheel.
(4) Remove four screws attaching lower bezel to in-
strument panel. (5) Lift lower cluster bezel from instrument panel.
(6) For installation reverse above procedures.
CLUSTER MASK AND LENS REMOVAL
(1) Remove cluster bezel.
(2) Remove trip reset knob by pulling straight
back. (3) Remove five screws attaching mask and lens to
cluster. (4) For installation reverse above procedures.
Fig. 4 Combination Oil Sending Unit
Fig. 5 Combination Oil Sending Unit Test
Fig. 6 Brake Warning Lamp Switch
Ä INSTRUMENT PANEL AND GAUGES 8E - 25

(3) With the ignition switch ON, an open (discon-
nected sending unit wire) causes the oil, fuel or tem-
perature gauge to read below low, empty or cold
indicators. (4) If steps 2 and 3 check OK, refer to the individ-
ual sending unit test procedures.
FUEL TANK SENDING UNIT TEST
Refer to Group 14, Fuel for test procedure.
CHECK GAUGES WARNING LAMP TESTS
The check gauges warning lamp will illuminated
when the ignition key is turned to the ON position.
The lamp will illuminate if the engine oil pressure
drops below a safe level. The check gauge lamp will
light for high engine temperature or for low voltage. To test the system turn ignition key to the ON po-
sition. If the lamp fails to light, inspect for a broken
or disconnected wire at the oil pressure combination
sending unit, which is located at the front of the en-
gine (Fig. 13). If the wire at the connector checks
good pull connector loose from the switch terminal
and with a jumper wire ground connector to the en-
gine. With the ignition key turned to the ON posi-
tion check the warning lamp. If lamp still fails to
light, inspect for a burned lamp. If lamp still fails to
light, inspect for a burned out lamp or disconnected
socket in the cluster.
To test the switch disconnect the switch electrical
connector. Attach positive lead of an ohmmeter to
the switch terminal for the gray (GY) wire and the
negative lead to an engine ground. With the engine
off, there should be continuity in the system. Start
the engine. With the engine running, the ohmmeter
should show no continuity. If the above results are
not obtained, replace the switch.
COMBINATION OIL SENDING UNIT TEST
The combination oil sending unit has two func-
tions: (1) The normal closed circuit keeps the oil pressure
warning lamp on until there is oil pressure. (2) The sending unit provides a resistance that
varies with oil pressure. To test the normally closed oil lamp circuit, discon-
nect the locking connector and measure the resis-
tance between the switch terminal and the metal
housing. The ohmmeter should read 0 ohms. Start
the engine (Fig. 14).
If there is oil pressure, the ohmmeter should read
an open circuit. To test the sending unit, measure the resistance
between the sending unit terminal and the metal
housing. The ohmmeter should read open. Start the
engine. The ohmmeter should read between 30 to 55 ohms,
depending on engine speed, oil temperature, and oil
viscosity. If the above results are not obtained, replace the
sending unit.
SEAT BELT WARNING SYSTEM
For testing of this system refer to Group 8U,
Chime Warning/Reminder System.
MALFUNCTION INDICATOR (CHECK ENGINE) SYSTEM
For testing this system refer to the Body Diagnos-
tic Procedures booklet.
BRAKE SYSTEM WARNING LAMP TEST
The brake warning lamp illuminates when parking
brake is applied with ignition key turned ON. The
same lamp will also illuminate should one of the two
service brake systems fail when brake pedal is ap-
plied. To test system turn ignition key ON, and ap-
ply parking brake. If lamp fails to light, inspect for a
burned out lamp, disconnected socket, a broken or
disconnected wire at switch. The lamp also lights
when the ignition switch is turned to START. Refer
to Brake System Warning Lamp Diagnosis Chart
(Fig. 15). To test service brake warning system, raise vehicle
on a hoist and open a wheel cylinder bleeder while aFig. 13 Combination Oil Sending Unit
Fig. 14 Combination Oil Sending Unit Test
Ä INSTRUMENT PANEL AND GAUGES 8E - 47

AP BODY INDEX
page page
Cluster and Gauge Service and Testing ....... 58
Gauges ................................ 61
General Information ....................... 58 Instrument Panel Replacement
.............. 72
Interior Lamp Replacement ................. 73
Switch and Panel Component Service ......... 67
GENERAL INFORMATION
INSTRUMENT CLUSTER
There are two conventional instrument cluster as-
semblies available. The clusters incorporates mag-
netic type gauges and an electronically driven
speedometer and odometer assembly (Fig. 1 and 2).
MAGNETIC GAUGES
All gauges on the AP Body clusters are the mag-
netic type gauges. When the ignition switch is in the
OFF position each gauge, except for the voltmeter
and tachometer will show a reading. However, the
readings are only accurate when the ignition switch
is in the ON position.
TACHOMETER DRIVE MODULE
The tachometer drive module is an electronic mod-
ule used to drive the magnetic tachometer in the
high line cluster. This module is located on top of the instrument
cluster.
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. 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
under the individual radio operating instructions re-
fer to the Sound Systems Manual supplied with the
vehicle.
WARNING LAMPS AND INDICATOR LIGHTS
The instrument cluster has warning and indicators
lamps for eight different systems:
² Low oil pressure
² Brake warning
² Seat belt warning
² Malfunction indicator (check engine) lamp
² Air Bag
² High beam indicator
² Right and left turn signals.
² Anti-lock (ABS)
CLUSTER AND GAUGE SERVICE AND TESTING
CAUTION: Disconnect the negative battery cable
before servicing the instrument panel. When power
is required for test purposes, reconnect battery ca-
ble for test only. Disconnect the negative battery
cable after test and before continuing service pro-
cedures.
SENDING UNIT TEST
Check for a defective sending unit or wiring, when
a problem occurs with a cluster gauge. Do this before
disassembling the cluster. (1) Sending units and wiring can be checked by
grounding the connector leads, at the sending unit,
in the vehicle. (2) With the ignition in the ON position, a
grounded input will cause the fuel or temperature
gauge to read at or above maximum.
Fig. 1 Instrument Cluster With Tachometer
Fig. 2 Instrument Cluster Without Tachometer
8E - 58 INSTRUMENT PANEL AND GAUGES Ä

FUEL TANK SENDING UNIT TEST
Refer to Group 14, Fuel for test procedures.
LOW OIL PRESSURE WARNING LAMP TEST
The low oil pressure warning lamp will illuminate
when the ignition key is turned to the ON position
without engine running. The lamp also illuminates
should the engine oil pressure drop below a safe oil
pressure level. To test the system turn ignition key to the ON po-
sition. If the lamp fails to light, inspect for a broken
or disconnected wire at the oil pressure combination
unit, located at the front of the engine (Fig. 3). If the
wire at the connector checks good, pull connector
loose from the switch and with a jumper wire ground
connector to the engine. With the ignition key turned
to the ON position check the warning lamp. If lamp
still fails to light, inspect for a burned out lamp or
disconnected socket in the cluster.
COMBINATION OIL SENDING UNIT TEST
The combination oil sending unit has two func-
tions: (1) The normal closed circuit keeps the oil pressure
warning lamp on until there is oil pressure (Fig. 4).
(2) The sending unit provides a resistance that
varies with oil pressure. To test the normally closed oil lamp circuit, discon-
nect the locking connector and measure the resis-
tance between the switch terminal and the metal
housing. The ohmmeter should read continuity. Start
the engine. If there is oil pressure, the ohmmeter should read
an open circuit. To test the sending unit, measure the resistance
between the sending unit terminal and the metal
housing. The ohmmeter should no continuity. Start
the engine. The ohmmeter should read between 30 to 55 ohms,
depending on engine speed, oil temperature and oil
viscosity. If the above results are not obtained, replace the
sending unit.
SEAT BELT WARNING SYSTEM
For testing of this system refer to Group 8M, Re-
straint Systems.
AIR BAG WARNING SYSTEM
For testing of this system refer to Group 8M, Re-
straint Systems.
MALFUNCTION INDICATOR (CHECK ENGINE) SYSTEM
For testing of this system using DRB II, refer to
the Body Powertrain Diagnostic Procedures.
BRAKE SYSTEM WARNING LAMP TEST
The brake warning lamp illuminates when parking
brake is applied with ignition key turned ON. The
same lamp will also illuminate should one of the two
service brake systems fail when brake pedal is ap-
plied. Refer to Brake system warning Lamp Diagno-
sis (Fig. 5). To test system turn ignition key ON and apply
parking brake. If lamp fails to light, inspect for a
burned out lamp, disconnected socket, a broken or
disconnected wire at switch. The lamp also lights
when the ignition switch is turned to start. To test service brake warning system, raise vehicle
on a hoist and open a wheel cylinder bleeder while a
helper depresses brake pedal and observes warning
lamp. If lamp fails to light, inspect for a burned out
lamp, disconnected socket, a broken or disconnected
wire at switch. If lamp is not burned out and wire continuity is
proven, replace brake warning switch in brake line
Tee fitting mounted on frame rail in engine compart-
ment below master cylinder (Fig. 6).
CAUTION: If wheel cylinder bleeder was opened
check master cylinder fluid level.
Fig. 3 Combination Oil Sending Unit
Fig. 4 Combination Oil Sending Unit Test
Ä INSTRUMENT PANEL AND GAUGES 8E - 59

² If no short to ground at connector, check speaker
resistance at amplifier connector for an reading of
three to five ohms.
² If resistance is OK, refer to Radio Diagnosis. If ra-
dio checks OK, replace amplifier.
² If resistance is less than three ohms check
speaker. Check across the speaker connector if less
than three ohms replace speaker. If resistance is OK
repair wires
CONDITION: MECHANICAL NOISE DISTORTION
² Check trim for loose parts and speaker attach-
ments for buzzes
² Remove speaker still connected and listen for dis-
tortion. Distortion replace speaker.
CONDITION: ONE SPEAKER NON-OPERATIVE
² Remove output signal connector from amplifier
and check for three to five ohms resistance to the
non-operative speaker. Refer to Fig. 34 for the appro-
priate pin numbers.
² If resistance is less than three ohms, test speaker
for resistance.
² If OK repair wire. If not replace speaker.
CONDITION: ALL SPEAKERS NON-OPERATIVE
²Check radio for being ON, are the display lights
on
² Radio not ON, refer to Radio Diagnosis
² Check Amplifier Connectors and wires for proper
connection
² Check pin 9 and pin 27 for battery voltage
² If voltage OK replace amplifier ²
If pin 27 has battery voltage and pin 9 has 0 volt-
age. Refer to Power Antenna Diagnosis and test volt-
age at antenna relay.
² If pin 9 has battery voltage and pin 27 has 0 volt-
age. Check pin 27 for short to ground.
² If shorted to ground repair wire
² If no short to ground check fuse cavity number 16
for blown fuse.
² If fuse blows again replace amplifier
RELAY/CHOKEÐINFINITY SPEAKER
If the audio system is lacking bass, check for con-
tinuity across the relay and choke connectors. If no
continuity, replace relay/choke assembly (Fig. 35).
LOCATION
(1) AA and AP Bodies, attached to the reinforce-
ment above glove box. (2) AG Body, attached to the dimmer module bay-
onet bracket on the bulkhead behind the glove box.
Fig. 35 Relay/Choke Assembly
Ä AUDIO SYSTEM 8F - 29