1994 JEEP CHEROKEE Service Repair Manual

taching screws. Do not allow the ignition switch to
move from the ACCESSORY detent position.
Because the ignition switch and the headlamp dim-
mer switch share the same two mounting screws, one
of the screws must be removed from the ignition
switch. This must be doneafterthe ignition switch
has been adjusted andbeforethe dimmer switch has
been installed. Remove one screw.Do notremove
the stud/nut.
(7) Install the headlamp dimmer switch as follows:
Slip switch into actuator rod and position over the ig-
nition switch. Install screws finger tight. Remove the
dimmer switch actuator rod securing-tape from steer-
ing column.
(8) Adjust dimmer switch as follows: Depress the
switch slightly and insert a 3/32-inch drill bit into
the adjustment hole (Fig. 1). This is done to prevent
horizontal switch movement.
(9) Move switch toward steering wheel to remove
any lash from switch actuator rod. Tighten dimmer
and ignition switch fasteners to 4 Nzm (35 in. lbs.)
torque.
(10) XJ models: Install the lower instrument panel
trim assembly. YJ models: Install the windshield
wiper intermittent control module and its bracket (if
equipped).
(11) Install the negative battery cable.
Test dimmer switch. Test ignition switch operation
in all switch positions. If equipped with a tilt steer-
ing column, test operation of dimmer switch and ig-
nition switch in all tilt positions.
Fig. 4 Detent PositionsÐNon-Tilt Steering Column
Fig. 5 Detent PositionsÐTilt Steering Column
8D - 32 IGNITION SYSTEMSJ

SPECIFICATIONS
GENERAL INFORMATION
The following specifications are published from the
latest information available at the time of publica-
tion.If anything differs between the specifica-
tions found on the Vehicle Emission Control
Information (VECI) label and the following spec-
ifications, use specifications on VECI label.The
VECI label is located in the engine compartment.
SPARK PLUGS
ENGINE FIRING ORDERÐ2.5L ENGINE
ENGINE FIRING ORDERÐ4.0L ENGINE
TORQUE
JIGNITION SYSTEMS 8D - 33

INSTRUMENT PANEL AND GAUGES
GROUP INDEX
page page
INSTRUMENT PANEL AND GAUGESÐXJ..... 1INSTRUMENT PANEL AND GAUGESÐYJ.... 14
INSTRUMENT PANEL AND GAUGESÐXJE
CONTENTS
page page
INSTRUMENT CLUSTER DIAGNOSIS........ 3
INSTRUMENT CLUSTER GENERAL INFORMATION.. 1
INSTRUMENT CLUSTER SERVICE PROCEDURES... 5
SPECIFICATIONS....................... 13
INSTRUMENT CLUSTER GENERAL INFORMATION
INDEX
page page
4WD Indicator Lamp........................ 2
Anti-Lock Brake Indicator Lamp............... 2
Brake Indicator Lamp....................... 2
Coolant Temperature Gauge................. 1
Coolant Temperature Indicator Lamp........... 1
Fuel Gauge.............................. 2
Low Fuel Warning Lamp..................... 2Malfunction Indicator Lamp (Check Engine)...... 2
Oil Pressure Gauge....................... 1
Oil Pressure Indicator Lamp.................. 1
Speedometer/Odometer System.............. 2
Tachometer.............................. 2
Upshift Indicator Lamp...................... 2
Voltmeter............................... 1
With the ignition switch in the ON or START posi-
tion, voltage supplied to the instrument cluster is lim-
ited by fuse #17. The voltage is supplied to all the
gauges and indicator lamps through the instrument
cluster printed circuit.
With the ignition switch in the OFF position, volt-
age is not supplied to the instrument cluster and the
gauges do not indicate any vehicle condition.
VOLTMETER
The voltmeter measures battery or generator out-
put voltage, whichever is greater.
OIL PRESSURE GAUGE
The oil pressure gauge pointer position is controlled
by a magnetic field created by electrical current flow
through the coils within the gauge. A change in current
flow will change the magnetic field which changes the
pointer position. The oil pressure sender is a variable
resistor that changes electrical resistance with a change
in oil pressure (values shown in Specifications chart).
OIL PRESSURE INDICATOR LAMP
Voltage is supplied to one side of the indicator bulb
and the oil pressure switch is connected to the other
side. When oil pressure is too low the switch closes
providing a path to ground, and the indicator bulb
lights.
COOLANT TEMPERATURE GAUGE
The coolant temperature gauge pointer position is
controlled by a magnetic field created by electrical
current flow through the coils within the gauge. A
change in current flow will change the magnetic field
which changes the pointer position. The coolant tem-
perature sensor is a thermistor that changes electri-
cal resistance with a change in coolant temperature
(values shown in Specifications chart).
COOLANT TEMPERATURE INDICATOR LAMP
Voltage is supplied to one side of the indicator bulb
and the coolant temperature switch is connected to the
JINSTRUMENT PANEL AND GAUGES 8E - 1

other side. When coolant temperature is too high the
switch closes providing a path to ground, and the indi-
cator bulb lights.
TACHOMETER
The tachometer displays the engine speed (RPM).
With the engine running, the tachometer receives an
engine speed signal from the Powertrain Control
Module pin 43 (values shown in Specifications chart).
SPEEDOMETER/ODOMETER SYSTEM
The speedometer/odometer system consists of an elec-
tric speedometer and pushbutton reset odometer
mounted in the cluster. The system also includes the
wire harness from the cluster to the vehicle speed sen-
sor at the transmission, and the adapter and pinion in
the transmission. A signal is sent from a transmission
mounted vehicle speed sensor to the speedometer/odom-
eter circuitry through the wiring harness. Refer to
Group 21 - Transmission for selecting the proper pinion,
and selecting and indexing the proper adapter.
FUEL GAUGE
The fuel gauge pointer position is controlled by a
magnetic field created by electrical current flow through
the coils within the gauge. A change in current flow will
change the magnetic field which changes the pointer po-
sition. The fuel level sender is a variable resistor that
changes electrical resistance with a change of the level
of fuel in the tank (values shown in Specifications
chart).
LOW FUEL WARNING LAMP
The low fuel warning lamp will light when the fuel
level falls below approximately 4 gallons. A low fuel
warning module controls when the lamp will light.
When the module senses 66.5 ohms or less from the
fuel level sender for 10 continuous seconds, the lamp
will light. The lamp will remain on until the module
senses 63.5 ohms or more from the fuel level sender
for 20 continuous seconds.
UPSHIFT INDICATOR LAMP
Vehicles equipped with manual transmissions have an
optional upshift indicator lamp. The lamp is controlled
by the Powertrain Control Module. The lamp lights to
indicate when the driver should shift to the next high-
est gear for best fuel economy. The Powertrain Control
Module will turn the lamp off after 3 to 5 seconds if the
upshift is not performed. The lamp will remain off until
the vehicle stops accelerating and is brought back to the
range of lamp operation or shifted into another gear.
The indicator lamp is normally illuminated when
the ignition switch is turned ON and is turned off
when the engine is started. The lamp will be lighted
during engine operation according to engine speed
and load.
BRAKE INDICATOR LAMP
The brake indicator lamp warns the driver that the
parking brake is applied or that hydraulic pressure in
the split brake system is unequal.
Voltage is supplied through the brake indicator
bulb to 3 switches. A path to ground for the current
is available if:
²The brake warning switch is closed (with unequal
brake system hydraulic pressures), or
²
The ignition switch is in the START position (to test
the bulb), or
²The park brake switch is closed (with the parking
brake applied).
ANTI-LOCK BRAKE SYSTEM (ABS) INDICATOR
LAMP
The anti-lock brake system (ABS) lamp lights to in-
dicate a system self-check is in process at vehicle
start-up. If light remains on after start-up or comes
on and stays on while driving, it may indicate that
the ABS system has detected a malfunction or has
become inoperative.
4WD INDICATOR LAMP
COMMAND-TRAC 4WD
The PART TIME lamp lights when the vehicle is en-
gaged in four-wheel drive mode. Voltage is supplied to
one side of the indicator bulb. A switch in the transfer
case area is connected to the other side of the indicator
bulb. When the switch is closed, a path to ground is pro-
vided and the indicator bulb lights.
SELECT-TRAC 4WD
The four-wheel drive icon or FULL TIME lamp
lights when the vehicle is engaged in full time four-
wheel drive mode. The PART TIME lamp lights when
the vehicle is in part time four-wheel drive mode.
Voltage is supplied to one side of the indicators.
Switches in the transfer case area are connected to
the other side of the indicator bulbs. When a switch
is closed, a path to ground is provided and the indi-
cator bulb lights.
MALFUNCTION INDICATOR LAMP (CHECK ENGINE)
The Malfunction Indicator Lamp (Check Engine)
lights each time the ignition switch is turned ON and
stays on for 3 seconds as a bulb test.
If the PCM receives an incorrect signal or no signal
from certain sensors or emission related systems the
lamp is turned on (pin 32 of PCM). This is a warning
that the PCM has recorded a system or sensor mal-
function. In some cases when a diagnostic trouble
code is declared the PCM will go into a limp-in mode
in an attempt to keep the system operating. It sig-
nals an immediate need for service.
The lamp also can be used to display diagnostic
trouble codes (DTC). Cycle the ignition switch ON,
OFF, ON, OFF, ON within 5 seconds. This will allow
any trouble codes stored in the PCM memory to be
displayed in a series of flashes representing digits.
8E - 2 XJ INSTRUMENT PANEL AND GAUGESJ

INSTRUMENT CLUSTER DIAGNOSIS
INDEX
page page
4WD Indicator Inoperative................... 4
Anti-Lock Indicator......................... 4
Brake Indicator Inoperative.................. 4
Coolant Temperature Gauge Inoperative........ 3
Coolant Temperature Indicator Inoperative....... 3
Fuel Gauge Inoperative..................... 3
Gauges and Indicators Inoperative............ 3
Instrument Panel Lamps.................... 4
Low Fuel Warning Inoperative................ 4
Low Washer Indicator Inoperative............. 4Malfunction Indicator Lamp (Check Engine)...... 4
Oil Pressure Gauge Inoperative............... 3
Oil Pressure Indicator Inoperative............. 3
Radio/Clock Illumination.................... 4
Seat Belt Indicator........................ 4
Speedomete/Odometer Inoperative............. 3
Tachometer Inoperative..................... 3
Upshift Indicator Inoperative................. 4
Voltmeter Inoperative....................... 3
SPEEDOMETER/ODOMETER INOPERATIVE
(1) Check for continuity in the wire between the
vehicle speed sensor and cluster connector pin A5.
(2) With the ignition switch in the ON position,
check for battery voltage across pin A8 (B+) and pin
B2 (ground).
(3) Perform vehicle speed sensor test. Refer to the
appropriate vehicle Diagnostic Test Procedures man-
ual.
(4) If all the previous tests prove good, replace
speedometer/odometer.
GAUGES AND INDICATORS INOPERATIVE
(1) Remove and inspect fuse #17. Replace as re-
quired.
(2) Measure resistance at instrument cluster con-
nector terminal A3. Meter should read zero ohms. If
not, repair open to ground.
VOLTMETER INOPERATIVE
(1) Turn ignition switch to ON. Voltmeter should
read battery voltage. If not, go to step 2.
(2) Measure voltage at instrument cluster connec-
tor terminal A8. Meter should read battery voltage.
If OK, replace meter. If not, repair open to fuse #17.
OIL PRESSURE GAUGE INOPERATIVE
(1) Turn ignition switch to ON.
(2) Disconnect oil pressure sender connector (Fig.
1). Needle goes to H. If not, go to step 3.
(3) Touch oil pressure sender connector to ground.
Needle goes to L. If OK, replace sender. If not, repair
open to gauge (instrument cluster connector terminal
B7).
OIL PRESSURE INDICATOR INOPERATIVE
(1) Turn ignition switch to ON.
(2) Touch oil pressure switch connector to ground.
Lamp should light. If OK, replace switch. If bulb is
OK, repair open to instrument cluster connector ter-
minal B7.
COOLANT TEMPERATURE GAUGE INOPERATIVE
(1) Turn ignition switch to ON.
(2) Disconnect coolant temperature sender connec-
tor. Needle goes to C. If not, go to step 3.
(3) Touch coolant temperature sender connector to
ground. Needle goes to H. If OK, replace sender. If
not, repair open to gauge (instrument cluster connec-
tor terminal A1).
COOLANT TEMPERATURE INDICATOR
INOPERATIVE
(1) Turn ignition switch to ON.
(2) Touch coolant temperature indicator connector
to ground. Lamp should light. If OK, replace switch.
If bulb is OK, repair open to instrument cluster con-
nector terminal A1.
TACHOMETER INOPERATIVE
Tachometer input is from the Powertrain Control
Module pin 43. Use the DRB scan tool to test.
FUEL GAUGE INOPERATIVE
(1) Turn ignition switch to ON.
(2) Disconnect fuel gauge sender connector. Needle
should go to E.
Fig. 1 Oil Pressure Sending UnitÐ4.0L
JXJ INSTRUMENT PANEL AND GAUGES 8E - 3

(3) Connect a jumper between terminal A and B on
the body half of the fuel gauge sender connector. The
gauge should move to F. If gauge is OK, replace
sender. If not, go to step 4.
(4) Measure resistance of sender. Meter should
read 105 to 5 ohms. If OK, go to step 5. If not, re-
place sender.
(5) Check for an open between sender connector
and gauge. If OK, replace gauge. If not, repair open
to gauge.
LOW FUEL WARNING INOPERATIVE
(1) Turn ignition switch to ON.
(2) Disconnect terminal B1 of the instrument clus-
ter connector. Wait at least 10 seconds. Lamp (LED)
should light. If OK, replace sender. If not, replace
low fuel warning module.
UPSHIFT INDICATOR INOPERATIVE
(1) Turn ignition switch to ON.
(2) Ground pin 7 of connector B. Lamp should
light. If not, replace bulb. If OK, continue with
step 3.
(3) Turn ignition switch to OFF. Check for conti-
nuity between connector B pin 2 and pin 54 of the
Powertrain Control Module. If OK, replace PCM. If
not, repair open.
BRAKE INDICATOR INOPERATIVE
(1) Turn ignition switch to ON. Apply parking
brake, brake warning switch connector unplugged.
(2) Jumper brake warning switch connector termi-
nal B to ground. Lamp should light. If bulb is OK,
repair open to indicator.
(3) Turn ignition switch to OFF. Measure resis-
tance between brake warning switch connector ter-
minal A and ground. Meter should read zero ohms. If
OK, check switch and/or brake system. If not, repair
open to park brake switch ground.
4WD INDICATOR INOPERATIVE
(1) Apply parking brake, start engine, vehicle in
4WD Lock or 4WD.
(2) Unplug switch and touch harness side of wire
to ground. Lamp should light. If OK, check switch
operation, replace if bad. If bulb is OK, repair open
to indicator.
LOW WASHER INDICATOR INOPERATIVE
(1) Turn ignition switch to ON.
(2) Jumper 12 volts to fluid level switch connector
terminal B. Lamp should light. If not, go to step 3.
(3) Measure resistance between terminal B and
ground. Meter should read zero ohms. If not, repair
open to bulb. If OK, go to step 4.
(4) Measure voltage at fluid level switch connector
terminal A. Meter should read battery voltage. If
OK, replace switch. If not, repair open to fuse.
MALFUNCTION INDICATOR LAMP (CHECK ENGINE)
(1) Turn ignition switch to ON.
(2) Jumper Powertrain Control Module terminal 2
to ground. Lamp should light. If bulb is OK, check
for open to instrument cluster connector terminal 2.
ANTI-LOCK INDICATOR
(1) Turn ignition switch to ON.
(2) Jumper instrument cluster connector terminal
6 to ground. Lamp should light. If bulb is OK, check
wiring for an open to module. Refer to Group 5 -
Brakes.
SEAT BELT INDICATOR
Jumper instrument cluster connector terminal 15
to 12 volts. Lamp should light. If not, replace bulb. If
OK, check wiring for an open to buzzer module. Re-
fer to Group 8U - Chime/Buzzer Warning Systems.
RADIO/CLOCK ILLUMINATION
With the ignition switch in ACCESSORY or ON,
power comes from the radio fuse. It then goes
through the normally closed contacts of the radio il-
lumination relay to the radio at connector terminal
11.
Pulling the headlamp switch to ON energizes the
radio illumination relay. This closes the normally
open contacts of the relay, and the brightness for the
radio display is controlled by the headlamp switch
rheostat. The back-lighting for the radio is also con-
trolled by the headlamp rheostat through radio con-
nector terminal 10.
Refer to Group 8F - Audio Systems, for radio illu-
mination relay diagnosis.
INSTRUMENT PANEL LAMPS
Voltage is supplied at all times from the 40 amp
Maxi fuse (located in the Power Distribution Center)
through the park lamps fuse to the headlamp switch.
The circuit continues through the instrument lamps
fuse to the individual instrument panel lamps to
ground. Lamp brightness is controlled by turning the
headlamp switch knob.
DIAGNOSIS
(1) Turn parking lamps ON.
(2) Check park lamps fuse. Replace as required.
(3) Check instrument lamps fuse. Replace as re-
quired.
(4) Measure voltage at battery side of instrument
lamps fuse with rheostat turned counterclockwise to
clockwise (LO to HI). Meter should read zero volts to
battery voltage. If not, replace headlamp switch.
(5) Measure resistance at ground side of instru-
ment lamps fuse with parking lamps OFF. Meter
should read almost zero ohms (except bulb filament).
If not, repair open to ground. If zero ohms, 12 volt
supply wire from fuse is shorted to ground, repair short.
8E - 4 XJ INSTRUMENT PANEL AND GAUGESJ

INSTRUMENT CLUSTER SERVICE PROCEDURES
INDEX
page page
Gauge ReplacementÐInstrument Cluster Removed.. 5
Gear Selector Indicator ReplacementÐInstrument
Cluster Removed........................ 6
Instrument Cluster Replacement.............. 5
Instrument Panel Replacement (Fig. 9)......... 8
Printed Circuit ReplacementÐInstrumentCluster Removed........................ 6
Speedometer ReplacementÐInstrument
Cluster Removed........................ 5
Tachometer ReplacementÐInstrument
Cluster Removed........................ 5
INSTRUMENT CLUSTER REPLACEMENT
(1) Disconnect negative cable from battery.
(2) Remove 4 instrument panel bezel attaching
screws and remove instrument panel bezel. Bezel is
snap fit at locations shown (Fig. 2).
(3) Remove cigar lighter housing attaching screws
(Fig. 3).
(4) Remove switch housing attaching screws (if
equipped).
(5) Remove instrument panel cluster attaching
screws.
(6) Pull out cluster assembly far enough to discon-
nect 2 multiple plugs and remove instrument cluster.
To install cluster, reverse the removal procedures.
GAUGE REPLACEMENTÐINSTRUMENT CLUSTER
REMOVED
(1) Remove cluster lens and gauge bezel (Fig. 4). If
equipped with trip odometer, gently pull knob off trip
odometer push pin.
(2) Remove gauge attaching screws from rear of
mounting bezel. Remove gauge from front.
(3) Install gauge. Install attaching screws.
(4) Install cluster bezel and lens.
(5) Install knob on trip odometer push pin.
SPEEDOMETER REPLACEMENTÐINSTRUMENT
CLUSTER REMOVED
(1) Remove cluster lens and gauge bezel. If
equipped with trip odometer, gently pull knob off trip
odometer push pin.
(2) Remove 6 mounting screws from cluster hous-
ing.
(3) Remove 3 screws from rear of cluster housing
(Fig. 5).
(4) Remove speedometer assembly including circuit
board.
(5) Install speedometer with 3 screws.
(6) Install gauge bezel and lens.
(7) Install knob on trip odometer push pin.
TACHOMETER REPLACEMENTÐINSTRUMENT
CLUSTER REMOVED
(1) Remove cluster lens and gauge bezel. If
equipped with trip odometer, gently pull knob off trip
odometer push pin.
Fig. 2 Instrument Bezel Removal/InstallationÐXJFig. 3 Instrument Cluster Removal/InstallationÐXJ
JXJ INSTRUMENT PANEL AND GAUGES 8E - 5