1995 JEEP CHEROKEE electrical

INSTRUMENT PANEL AND GAUGESÐYJ
CONTENTS
page page
INSTRUMENT PANEL AND GAUGESÐYJ..... 22
DIAGNOSIS............................ 23
GENERAL INFORMATION................. 20SERVICE PROCEDURES.................. 31
SPECIFICATIONS........................ 39
GENERAL INFORMATION
Following are general descriptions of major instru-
ment panel components. Refer to Group 8W - Wiring
Diagrams for complete circuit descriptions and dia-
grams.
INSTRUMENT PANEL
Modular instrument panel construction allows all
gauges and controls to be serviced from the front of
the panel. In addition, most instrument panel wiring
and heater components can be accessed without com-
plete instrument panel removal.
Removal of the left instrument cluster bezel allows
access to the main cluster assembly and most
switches. Removal of the center cluster bezel allows
access to the gauge package cluster assembly, the
heater controls, and the radio. Removal of the cluster
assemblies allows access to the individual gauges, il-
lumination and indicator lamp bulbs, printed cir-
cuits, and most wiring.
INSTRUMENT CLUSTERS
The instrument cluster used on YJ (Wrangler) mod-
els consists of two separate assemblies. The main
cluster assembly is located on the left side of the in-
strument panel, centered over the steering column
opening. The gauge package cluster assembly is lo-
cated near the center of the instrument panel. Each
cluster assembly is served by a separate printed cir-
cuit and wiring connector. Some variations of each
cluster exist due to optional equipment and regula-
tory requirements.
The main cluster assembly includes a speedometer/
odometer/trip odometer and a tachometer. It also in-
cludes provisions for the following indicator lamps:
²anti-lock brake system lamp
²brake warning lamp
²headlamp high beam indicator lamp
²malfunction indicator (Check Engine) lamp
²seat belt reminder lamp²turn signal indicator lamps
²upshift indicator lamp.
The gauge package cluster assembly includes a
four-wheel drive indicator lamp and the following
gauges:
²coolant temperature gauge
²fuel gauge
²oil pressure gauge
²voltmeter.
GAUGES
With the ignition switch in the ON or START posi-
tion, voltage is supplied to all gauges through the
two cluster printed circuits. With the ignition switch
in the OFF position, voltage is not supplied to the
gauges. A gauge pointer may remain within the
gauge scale after the ignition switch is OFF. How-
ever, the gauges do not accurately indicate any vehi-
cle condition unless the ignition switch is ON.
All gauges except the odometer are air core mag-
netic units. Two fixed electromagnetic coils are lo-
cated within the gauge. These coils are wrapped at
right angles to each other around a movable perma-
nent magnet. The movable magnet is suspended
within the coils on one end of a shaft. The gauge nee-
dle is attached to the other end of the shaft.
One of the coils has a fixed current flowing through
it to maintain a constant magnetic field strength.
Current flow through the second coil changes, which
causes changes in its magnetic field strength. The
current flowing through the second coil can be
changed by:
²a variable resistor-type sending unit (fuel level,
coolant temperature, or oil pressure)
²changes in electrical system voltage (voltmeter)
²electronic control circuitry (speedometer/odometer,
tachometer).
8E - 24 INSTRUMENT PANEL AND GAUGESÐYJJ

The gauge needle moves as the movable permanent
magnet aligns itself to the changing magnetic fields
created around it by the electromagnets.
COOLANT TEMPERATURE GAUGE
The coolant temperature gauge gives an indication
of engine coolant temperature. The coolant tempera-
ture sending unit is a thermistor that changes elec-
trical resistance with changes in engine coolant
temperature. High sending unit resistance causes
low coolant temperature readings. Low resistance
causes high coolant temperature readings. Sending
unit resistance values are shown in a chart in Spec-
ifications.
FUEL GAUGE
The fuel gauge gives an indication of the level of
fuel in the fuel tank. The fuel gauge sending unit has
a float attached to a swing-arm in the fuel tank. The
float moves up or down within the fuel tank as fuel
level changes. As the float moves, an electrical con-
tact on the swing-arm wipes across a resistor coil,
which changes sending unit resistance. High sending
unit resistance causes high fuel level readings. Low
resistance causes low fuel level readings. Sending
unit resistance values are shown in a chart in Spec-
ifications.
OIL PRESSURE GAUGE
The oil pressure gauge gives an indication of en-
gine oil pressure. The combination oil pressure send-
ing unit contains a flexible diaphragm. The
diaphragm moves in response to changes in engine
oil pressure. As the diaphragm moves, sending unit
resistance increases or decreases. High resistance on
the gauge side of the sending unit causes high oil
pressure readings. Low resistance causes low oil
pressure readings. Sending unit resistance values are
shown in a chart in Specifications.
SPEEDOMETER/ODOMETER
The speedometer/odometer give an indication of ve-
hicle speed and travel distance. The speedometer re-
ceives a vehicle speed pulse signal from the Vehicle
Speed Sensor (VSS). An electronic integrated circuit
contained within the speedometer reads and analyzes
the pulse signal. It then adjusts the ground path re-
sistance of one electromagnet in the gauge to control
needle movement. It also sends signals to an electric
stepper motor to control movement of the odometer
number rolls. Frequency values for the pulse signal
are shown in a chart in Specifications.
The VSS is mounted to an adapter near the trans-
fer case output shaft. The sensor is driven through
the adapter by a speedometer pinion gear. The
adapter and pinion vary with transmission, axle ratio
and tire size. Refer to Group 21 - Transmission and
Transfer Case for more information.
TACHOMETER
The tachometer gives an indication of engine speed
in Revolutions-Per-Minute (RPM). With the engine
running, the tachometer receives an engine speed
pulse signal from the Powertrain Control Module
(PCM). An electronic integrated circuit contained
within the tachometer reads and analyzes the pulse
signal. It then adjusts the ground path resistance of
one electromagnet in the gauge to control needle
movement. Frequency values for the pulse signal are
shown in a chart in Specifications.
TRIP ODOMETER
The trip odometer is driven by the same electronic
integrated circuit as the speedometer/odometer. How-
ever, by depressing the trip odometer reset knob on
the face of the speedometer, the trip odometer can be
reset to zero. The trip odometer is serviced only as a
part of the speedometer/odometer gauge assembly.
VOLTMETER
The voltmeter is connected in parallel with the bat-
tery. With the ignition switch ON, the voltmeter in-
dicates battery or generator output voltage,
whichever is greater.
INDICATOR LAMPS
All indicator lamps, except the four-wheel drive in-
dicator, are located in the main cluster tell-tale area
above the steering column opening. Each of the
lamps is served by the main cluster printed circuit
and cluster connector. The four-wheel drive indicator
lamp is located in the gauge package cluster and is
served by the gauge package printed circuit and clus-
ter connector.
Up to eleven indicator lamps can be found in the
tell-tale area of the main cluster. These lamps are ar-
ranged in two rows, with six lamps in the upper row
and five lamps in the lower row.
ANTI-LOCK BRAKE SYSTEM LAMP
The Anti-Lock Brake System (ABS) lamp is
switched to ground by the ABS module. The module
lights the lamp when the ignition switch is turned to
the START position as a bulb test. The lamp will
stay on for 3 to 5 seconds after vehicle start-up to in-
dicate a system self-test is in process. If the lamp re-
mains on after start-up, or comes on and stays on
while driving, it may indicate that the ABS module
has detected a system malfunction or that the system
has become inoperative. Refer to Group 5 - Brakes
for more information.
BRAKE WARNING LAMP
The brake warning lamp warns the driver that the
parking brake is applied or that the pressures in the
two halves of the split brake hydraulic system are
unequal. With the ignition switch turned ON, battery
JINSTRUMENT PANEL AND GAUGESÐYJ 8E - 25

AUDIO SYSTEMS
CONTENTS
page page
DIAGNOSIS............................. 2
GENERAL INFORMATION.................. 1SERVICE PROCEDURES................... 6
GENERAL INFORMATION
Following are general descriptions of major compo-
nents used in XJ (Cherokee)/YJ (Wrangler) audio sys-
tems. Refer to Group 8W - Wiring Diagrams for
complete circuit descriptions and diagrams.
RADIOS
Radio options for the XJ and YJ models include an
AM/FM stereo or an AM/FM stereo/cassette receiver.
Both units are Electronically-Tuned Radios (ETR)
and include a clock function. For more information
on radio features, setting procedures, and control
functions refer to the owner's manual.
IN-LINE FUSE
Each radio receives fused battery feed when the ig-
nition switch is in the ON or ACCESSORY position.
There is an additional in-line fuse in the back of the
radio chassis. The in-line fuse (Fig. 1) will blow to
protect the vehicle electrical system in the event of
internal radio failure.
IGNITION-OFF DRAW FUSE
All vehicles are equipped with an Ignition-Off
Draw (IOD) fuse that is removed when the vehicle is
shipped from the factory. This fuse feeds various ac-
cessories that require current when the ignition
switch is in the OFF position, including the clock and
radio station preset memory functions. The fuse is re-
moved to prevent battery discharge during vehicle
storage.The IOD fuse should be checked if the radio station
preset memory or clock functions are erratic or inop-
erative. The IOD fuse is located in the Power Distri-
bution Center (PDC). Refer to underside of PDC
cover for IOD fuse identification.
RADIO ILLUMINATION RELAY
All radios are connected to a radio illumination re-
lay. The relay controls the source of battery feed for
radio/clock display illumination.
When the park and headlamp switch is in the OFF
position, the radio illumination relay remains de-en-
ergized. The radio/clock display receives full battery
voltage through the normally closed contacts of the
relay. This results in the radio/clock display being il-
luminated at full brightness for easier visibility in
daylight.
When the park and headlamp switch is in the ON
position, the radio illumination relay coil is ener-
gized. With the relay coil energized, the normally
closed contacts of the relay open, and the normally
open contacts of the relay close. This causes the ra-
dio/clock display to receive battery feed through the
instrument panel dimmer switch. The display illumi-
nation brightness can now be adjusted with other
panel lamps for night visibility.
SPEAKERS
Speaker system options include two, four or six (XJ
only) speaker locations. On XJ model two-speaker
systems, one speaker is located in each front door.
Four-speaker systems add one speaker at each end of
a rear-mounted overhead sound bar. The premium
six-speaker option upgrades all the speakers in the
above locations, and adds one tweeter at each end of
the lower instrument panel.
On YJ model two-speaker systems, one speaker is
located at each end of the instrument panel. Four-
speaker systems add one speaker at each end of a
rear-mounted overhead sound bar.
Fig. 1 In-Line Fuse
JAUDIO SYSTEMS 8F - 1

SERVICE PROCEDURES
RADIO REMOVE/INSTALL - XJ
(1) Disconnect battery negative cable.
(2) Remove upper and lower steering column
shrouds and steering column to instrument panel be-
zel gap hider. If equipped with tilt steering, apply
tape to tilt mechanism on top of steering column to
protect instrument panel bezel from damage during
removal.
(3) Remove 4 instrument panel bezel attaching
screws (Fig. 4) and remove the bezel.
(4) Remove 2 radio attaching screws (Fig. 5).(5) Slide radio chassis out of instrument panel far
enough to disconnect radio electrical connector,
ground lead and antenna lead (Fig. 6). Remove radio
from instrument panel.
(6) To install radio, route harness above and to the
right of the radio cavity. Make radio harness, ground
and antenna connections.
(7) While installing the radio, make sure that clip
on top of radio (Fig. 7) is installed in mating slot of
instrument panel.
(8) Reverse removal procedures to complete instal-
lation.
SPEAKERS REMOVE/INSTALL - XJ
INSTRUMENT PANEL
(1) Remove parking brake retaining screw from
lower instrument panel (Fig. 8).
(2) Remove retaining screws and the lower instru-
ment panel (Fig. 9).
(3) Unplug wire harness connector.
(4) Remove speaker screws and speaker from lower
instrument panel (Fig. 10).
(5) Reverse removal procedures to install.
Fig. 4 Instrument Bezel Remove/Install - XJ
Fig. 5 Radio Mounting Screws Remove/Install - XJ
Fig. 6 Radio Wiring Remove/Install - XJ
Fig. 7 Radio Clip Install - XJ
8F - 6 AUDIO SYSTEMSJ

(9) Apply a rubberized undercoating material to
the splash panel screws.
RADIO REMOVE/INSTALL - YJ
(1) Disconnect battery negative cable.
(2) Remove center cluster bezel attaching screws
(Fig. 17).
(3) Remove radio bezel.
(4) Remove radio attaching screws.
(5) Disconnect radio antenna cable.
(6) Disconnect radio wire harness.
(7) Remove radio.
(8) Reverse removal procedures to install.
SPEAKERS REMOVE/INSTALL - YJ
INSTRUMENT PANEL - YJ
RIGHT SIDE
The speaker is located behind grille panel at right
end of the instrument panel.
(1) Reach up behind instrument panel and remove
4 stamped nuts holding the speaker in place.
(2) Disconnect speaker electrical connector and re-
move speaker.
LEFT SIDE
The speaker is located behind grille panel at left
end of the dash panel.
(1) Remove nuts that attach the park brake assem-
bly mounting studs to the dash panel. The nuts are
accessible from the engine compartment (Fig. 18).
CAUTION: If vehicle is equipped with a rear window
wiper, there is a ground wire attached to top of bolt
that attaches the park brake assembly to the instru-
ment panel.
(2) Remove bolt that attaches the park brake as-
sembly to the instrument panel and allow assembly
to fall out of the way.
(3) Reach up behind instrument panel and remove
4 stamped nuts holding speaker in place.
(4) Disconnect speaker electrical connector and re-
move speaker.
(5) Reverse removal procedures to install.
SOUND BAR - YJ
(1) Pull sound bar padding away from bar on the
passenger side (Fig. 19).
(2) Disconnect speaker harness connector located
on the passenger side at the sound bar.
Fig. 16 Disconnect Antenna Lead - XJ
Fig. 17 Center Cluster Bezel Remove/Install - YJ
Fig. 18 Park Brake Assembly - YJ
JAUDIO SYSTEMS 8F - 9

WARNING: THE USE OF VEHICLE SPEED CON-
TROL IS NOT RECOMMENDED WHEN DRIVING
CONDITIONS DO NOT PERMIT MAINTAINING ACONSTANT SPEED, SUCH AS IN HEAVY TRAFFIC
OR ON ROADS THAT ARE WINDING, ICY, SNOW
COVERED, OR SLIPPERY.
DIAGNOSIS
Before beginning diagnosis, perform a vehicle road
test to verify reports of speed control system mal-
function. The road test should include attention to
the speedometer. Speedometer operation should be
smooth and without flutter at all speeds.
Flutter in the speedometer indicates a problem
which might cause surging in the speed control sys-
tem. The cause of any speedometer problems should
be corrected before proceeding. Refer to Group 8E -
Instrument Panel and Gauges for speedometer diag-
nosis.
If a road test verifies a system problem and the
speedometer operates properly, check for:
(1) Loose or corroded electrical connections at the
servo. Corrosion should be removed from electricalterminals and a light coating of Mopar MultiPurpose
Grease, or equivalent, applied.
(2) Correct installation of the vacuum check valve
in the hose from servo to vacuum source. The word
VAC on the valve must point toward the vacuum
source.
(3) Loose or leaking vacuum hoses or connections.
(4) Secure attachment of both ends of the speed
control servo cable.
CAUTION: When test probing for voltage or conti-
nuity at electrical connectors, care must be taken
not to damage connector, terminals, or seals. If
these components are damaged, intermittent or
complete system failure may occur.
Fig. 1 Vehicle Speed Control System
8H - 2 VEHICLE SPEED CONTROL SYSTEMJ

SERVICE PROCEDURES
SPEED CONTROL SERVO REMOVE/INSTALL
(1) Disconnect battery negative cable.
(2) Disconnect vacuum hose at servo.
(3) Remove 2 nuts on servo cable sleeve.
(4) Pull speed control cable away from servo to ex-
pose cable retaining clip (Fig. 9).
(5) Remove clip attaching cable to servo.
(6) Pull servo away from mounting bracket.
(7) To install, insert servo studs through holes in
sevo mounting bracket.
(8) Block throttle to full open position, align hole
in cable sleeve with hole in servo pin and install re-
taining clip.
(9) Reverse remaining removal procedures to in-
stall. Tighten servo mounting nuts to 6 Nzm (50 in.
lbs.).
SPEED CONTROL SWITCH REMOVE/INSTALL
WARNING: ON VEHICLES EQUIPPED WITH AN AIR-
BAG, REFER TO GROUP 8M - RESTRAINT SYS-
TEMS BEFORE ATTEMPTING STEERING WHEEL
COMPONENT DIAGNOSIS OR SERVICE. FAILURE
TO TAKE PROPER PRECAUTIONS COULD RESULT
IN ACCIDENTAL AIRBAG DEPLOYMENT AND POS-
SIBLE PERSONAL INJURY.
(1) Disconnect negative cable from battery.
(2) From underside of steering wheel, remove
speed control switch mounting screws (Fig. 10).
(3) Pull switches from wheel and unplug connector.
(4) Plug electrical connector into new switches.
(5) Install new switches with 2 screws.
Fig. 9 Servo Cable Remove/Install
Fig. 10 Speed Control Switch Remove/Install -
Typical
JVEHICLE SPEED CONTROL SYSTEM 8H - 9

allowing current flow to the lamps. As the bimetal
strip cools, the contact points are pushed open and
the cycle repeats.
COMBINATION FLASHER (XJ ONLY)
The combination flasher functions as both the turn
signal and hazard warning flasher on XJ models. The
combination flasher is a smart relay that is located in
the relay center under the lower instrument panel
and inboard of the steering column. The combination
flasher can not be repaired. If faulty, it must be
replaced.
The combination flasher is designed to handle the
current flow requirements of the factory installed
lighting. If supplemental lighting is added to the turn
signal circuits such as when towing a trailer with
lights, the combination flasher will automatically
compensate. This allows the flash rate to remain the
same, regardless of electrical load increases. However,
if a bulb fails in the turn signal or hazard warning
circuits, the flash rate of the remaining bulbs in that
circuit will increase to 120 flashes per minute or
higher.
TURN SIGNAL/HAZARD WARNING SWITCH
(YJ ONLY)
The turn signal and hazard warning switches are
combined into a single unit mounted within the upper
steering column bowl and beneath the steering wheel.
The turn signal lever on the left side of the steering
column is moved up or down to select the right or left
turn signal switch position. The turn signals will only
operate with the ignition switch in the ACCESSORY
or ON position.
The hazard warning button on the right side of the
steering column is pushed in to turn the hazard
warning system on, or pulled out to turn the system
off. The hazard warning system will operate regard-
less of ignition switch position. The turn signal/haz-
ard warning switch can not be repaired. If faulty, the
entire unit must be replaced.
MULTI-FUNCTION SWITCH (XJ ONLY)
The multi-function switch assembly (Fig. 1) is
mounted to the left side of the steering column. This
switch contains electrical circuitry for the following
functions:²turn signals
²hazard warning
²headlamp beam selection
²headlamp optical horn
²windshield wipers
²windshield washers.
The information contained in this group addresses
only the switch functions for the turn signal and
hazard warning circuits. For information relative to
other switch functions, refer to the appropriate group.
However, the multi-function switch can not be re-
paired. If any function of the switch is faulty, the
entire switch assembly must be replaced.
TURN SIGNAL INDICATOR LAMPS
These lamps are located in the instrument cluster.
They flash with the exterior turn signal lamps to give
the driver a visual indication that a turn signal or the
hazard warning circuit is operating. For diagnosis
and service of this component, refer to Group 8E -
Instrument Panel and Gauges.
TURN SIGNAL LAMPS
The exterior lamps included in the turn signal and
hazard warning circuits include: the front park/turn
signal, and the rear tail/stop/turn signal. For diagno-
sis and service of these lamps, refer to Group 8L -
Lamps.
Fig. 1 Multi-Function Switch
8J - 2 TURN SIGNAL AND HAZARD WARNING SYSTEMSJ