1994 JEEP CHEROKEE fuse chart

scan tool will be necessary to determine which ABS
component has malfunctioned.
ABS Light Illuminates During Brake Stop
A system fault such as loss of speed sensor signal
or solenoid failure, will cause the amber warning
light to illuminate. The most effective procedure here
is to check for obvious damage first. Then check the
electronic components with the DRB II scan tool.
BRAKE WARNING LIGHT DISPLAY
The red brake warning light and the ABS light op-
erate independently. If the red light remains on after
startup or illuminates during a brake stop, refer to
the standard brake system diagnosis section. Either
the parking brakes are applied, or a wheel brake
malfunction has occurred.
ECU DIAGNOSIS
The ECU controls all phases of antilock system op-
eration. It also differentiates between normal and an-
tilock mode braking.
The ECU monitors and processes the signals gen-
erated from all of the system sensors at all times.
The ECU program includes a self check routine
that tests each of the system components. The self
check occurs during both phases of the initialization
program. A failure of the self check program will
cause the immediate illumination of the amber warn-
ing light. The light will also illuminate if a solenoid
or other system component fails during the dynamic
phase of initialization.
If a system malfunction should occur, do not imme-
diately replace the ECU. A blown system fuse, bad
chassis ground, or loss of feed voltage will each cause
a system malfunction similar to an ECU failure.
Never replace the ECU unless diagnosis with the
DRB II scan tool indicates this is necessary.
HCU DIAGNOSIS
The HCU pump and motor and solenoid valve body
are serviced only as an assembly. The HCU assembly
should not be replaced unless a fault has actually
been confirmed. Verify fault conditions with the DRB
II scan tool before proceeding with repair.
ABS SYSTEM WIRING AND ELECTRICAL CIRCUITS
Location of the ABS fuse (in the fuse panel) is
shown in Figure 1. The engine compartment harness
routing for the ABS components is shown in Figure 2.
ABS FAULT DIAGNOSIS
The fault diagnosis chart provides additional infor-
mation on potential ABS system faults. Use the
chart as a guide when diagnosing a system problem.
Fig. 1 ABS Fuse Location
5 - 4 BRAKESJ

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

INSTRUMENT PANEL AND GAUGESÐYJE
CONTENTS
page page
GAUGE PACKAGE DIAGNOSIS............ 22
GAUGE PACKAGE GENERAL INFORMATION . 22
GAUGE PACKAGE SERVICE PROCEDURES . . 24
INSTRUMENT CLUSTER DIAGNOSIS....... 14INSTRUMENT CLUSTER GENERAL INFORMATION.14
INSTRUMENT CLUSTER SERVICE PROCEDURES.. 17
SPECIFICATIONS....................... 27
INSTRUMENT CLUSTER GENERAL INFORMATION
SPEEDOMETER/ODOMETER SYSTEM
The speedometer/odometer system consists of an
electric speedometer and pushbutton reset odometer
mounted in the cluster. The system also includes the
wire harness from the cluster to the vehicle speed
sensor at the transmission, and the adapter and pin-
ion in the transmission. A signal is sent from a
transmission mounted vehicle speed sensor to the
speedometer/odometer circuitry through the wiring
harness. Refer to Group 21 - Transmission for select-
ing the proper pinion, and selecting and indexing the
proper adapter.
TACHOMETER
The tachometer displays the engine speed (RPM).
With the engine running, the tachometer receives anengine speed signal from the Powertrain Control
Module pin 43 (values shown in Specifications chart).
INDICATOR LAMPS
The Brake, Upshift (2.5L with 5 speed transmis-
sion except California), and Malfunction Indicator
(Check Engine) lamps are located in the indicator
lamp panel above the steering column. The lamps
share a common battery feed connection through the
ignition switch and fuse #9.
The turn signals, high beam indicator, seat belt re-
minder, hazard lamp, master lighting and illumina-
tion bulbs are supplied battery voltage through
various switches and share a common ground.
INSTRUMENT CLUSTER DIAGNOSIS
INDEX
page page
Brake Indicator Lamp...................... 16
DiagnosingÐAll Lamps Out................. 16
Instrument Panel Illumination Lamps.......... 16
Malfunction Indicator Lamp (Check Engine)..... 16Seat Belt Reminder Lamp................... 16
Speedometer............................ 14
Tachometer............................. 14
Upshift Indicator Lamp..................... 16
SPEEDOMETER
(1) Raise vehicle.
(2) Disconnect the vehicle speed sensor connector.
(3) Connect a voltmeter between the black wire
pin of the connector and ground.
(4) Turn the ignition switch to the ON position.
(5) Check for approximately 5 volts. If OK, per-
form vehicle speed sensor test. Refer to the appropri-
ate Powertrain Diagnostic Procedures manual. If not
OK, continue with step 6.
(6) Turn ignition switch to OFF position.(7) Check continuity between vehicle speed sensor
connector and terminal 13 of instrument cluster con-
nector. If OK, replace speedometer. If not OK, repair
open circuit.
TACHOMETER
(1) Tachometer input is from the Powertrain Con-
trol Module (PCM) pin 43. Use the DRB scan tool to
perform actuator test. If OK, continue with step 2. If
not, replace PCM.
(2) Check for continuity between cluster connector
pin 12 and PCM pin 43. If OK, replace tachometer. If
not, repair open circuit.
8E - 14 YJ INSTRUMENT PANEL AND GAUGESJ

GAUGE PACKAGE GENERAL INFORMATION
The gauge package contains 4 gauges and the 4
wheel drive indicator. The gauges have a common
battery feed from fuse #9 and ignition switch. Al-
though they have separate power sources, the 4
gauges share a common ground connection.
The voltmeter indicates electrical system voltage.
When the engine is not running, the voltage regis-
tered is from the battery. After the engine is started,
charging system voltage is indicated. In the gauge
package, the voltmeter forms a parallel connectionacross the battery feed and ground.
The remaining gauges - oil pressure, fuel and cool-
ant temperature - are connected to individual sender
units. Variable resistors in the senders will change
the amount of current allowed to flow through the
gauge coils. As current flow through the coils varies,
the position of the indicator needle also will vary.
The 4 gauges are connected to battery feed, ground
and the sender units through a printed circuit
mounted on the back of the gauge housing.
GAUGE PACKAGE DIAGNOSIS
ALL GAUGES INOPERATIVE (Fig. 15)
(1) Check the fuse #9. Replace as required.
(2) Turn ignition switch to ON and measure volt-
age at battery side of fuse #9. Meter should read bat-
tery voltage. If not, repair open from ignition switch.
(3) Unplug gauge package connector from gauge
package.
(4) Turn ignition switch to OFF and measure resis-
tance from instrument cluster connector terminals 1
and 13 to a clean chassis ground. Meter should read
zero ohms. If not, repair open to ground.
(5) Turn ignition switch to ON and measure volt-
age at instrument cluster connector terminals 2 and
12. Meter should read battery voltage. If not, repair
open from fuse panel.
ONE GAUGE INOPERATIVE
Does not apply to voltmeter.
OIL PRESSURE SENDER
(1) Turn ignition switch to ON.
(2) Unplug oil pressure sender connector from oil
pressure sender.
(3) Touch connector to engine block (ground).
Gauge should read at low end of scale.
(4) When connector is NOT touching ground (open
circuit) gauge should read at high end of scale. If OK
replace sender. If not, proceed with step 5.
(5) Check circuit between sender and gauge for an
open. Repair as required. If wiring is OK, replace
gauge.
COOLANT TEMPERATURE SENDER
(1) Turn ignition switch to ON.
(2) Unplug coolant temperature sender connector
from coolant temperature sender.
(3) Touch connector to engine block (ground).
Gauge should read at high end of scale.
(4) When connector is NOT touching ground (open
circuit) gauge should read at low end of scale. If OK
replace sender. If not, proceed with step 5.
(5) Check circuit between sender and gauge for an
open. Repair as required. If wiring is OK, replace
gauge.
FUEL GAUGE SENDER
(1) Turn ignition switch to ON.
(2) Separate fuel gauge sender connector from fuel
gauge sender near tank.
(3) Ground the center wire of the body harness
side of the connector. The gauge should read at low
end of scale. If OK, check sending unit (step 4). If
not, check circuit between connector and gauge. Re-
pair as required. If circuit is OK, replace gauge.
(4) Turn ignition switch to OFF.
(5) Measure resistance from fuel gauge sender con-
nector center terminal to a clean chassis ground.
Meter readings should correspond to those shown in
Specifications. If not OK, replace sender. If OK, re-
pair open from fuel gauge sender connector to
ground.
PRINTED CIRCUIT
(1) Turn ignition switch to ON.
(2) Unplug gauge package connector from gauge
package.
(3) Measure resistance from gauge package termi-
nal 12 (fuel and coolant temperature gauge) or from
terminal 2 (voltmeter and oil pressure gauge) to
gauge battery terminal. Meter should read zero
ohms. If not, replace/repair printed circuit.
(4) Measure resistance from gauge package termi-
nal 13 (fuel and coolant temperature gauge) or from
terminal 1 (voltmeter and oil pressure gauge) to
gauge ground terminal. Meter should read zero
ohms. If not, replace/repair printed circuit. If zero
ohms, replace gauge.
GAUGE CALIBRATION VALUES
Use the charts in Specifications. The calibration of
the gauge can be checked. If the indicator needle is
not in the correct position, replace the gauge.
4WD INDICATOR
The four-wheel drive indicator lamp circuit is com-
pleted by the Command-Trac switch located below
the battery.
8E - 22 YJ INSTRUMENT PANEL AND GAUGESJ

WIRING DIAGRAMS
CONTENTS
page page
FUSE CHARTS AND RELAY BANKS......... 8
GENERAL INFORMATION.................. 1
SPLICE LOCATIONS..................... 53
WIRING AND COMPONENT IDENTIFICATION . 13WIRING DIAGRAMS XJ.................. 149
WIRING DIAGRAMS XJ RHD............. 271
WIRING DIAGRAMS YJ.................. 73
GENERAL INFORMATION
INDEX
page page
Circuit Identification........................ 2
Component Identification.................... 2
Connector and Terminal Assembly Replacement . . 5
Connector Replacement.................... 4
Connectors.............................. 3
Fusible Link Replacement................... 4
Fusible Links............................. 3
Locating A System........................ 2Secondary Ignition Wiring................... 1
Splice Locations.......................... 2
Symbols, Fuses and Abbreviations............ 6
Terminal Replacement...................... 5
Troubleshooting Wiring Problems.............. 3
Wire Code Identification.................... 2
Wiring Diagram Sheets and Indexes........... 1
Wiring Repair............................ 4
The wiring diagrams contain the latest information
at the time of publication.
Throughout this group references may be made to
a particular vehicle by letter or number designation.
A chart showing the breakdown of these designations
is included in the Introduction Section at the front of
this service manual.
SECONDARY IGNITION WIRING
Secondary ignition wiring is shown in Figures 1
and 2. For additional information on ignition systems
or distributor operation refer to Group 8D Ignition
Systems.
WIRING DIAGRAM SHEETS AND INDEXES
The diagrams are organized to show the basic ve-
hicle and all of its options. Add-on or non-factory op-
tions are not covered. The diagram pages are
identified by a sheet number which is located at the
lower right or left hand corner of each sheet.Page
numbers at the top of each page do not apply to
diagram sheets.
Diagram sheets show all information relating to
the system. This includes feeds, grounds, switch in-
ternal circuity, connectors, splices, and pin identifica-
tion for controllers and modules. All components,switches, and relays are shown in the at rest position
with the key removed from the ignition and the doors
closed.
In certain instances a wire may be referenced to
another sheet. When this happens, the wire will be
identified as to where it is going.
The index used for the diagrams is located at the
beginning of the section. The main system and all re-
lated components are covered.
Fig. 1 Secondary Ignition Wiring 2.5L
JWIRING DIAGRAMS 8W - 1

WIRE CODE IDENTIFICATION
Each wire shown in the diagrams contains a code
(Fig. 3) which identifies the main circuit, part of the
main circuit, gauge of wire, and color. The color is
shown as a two letter code which can be identified by
referring to the Wire Color Code Chart (Fig. 4). If the
wire has a tracer and it is a standard color an aster-
isk will follow the main wire color. If the tracer is
non-standard the main wire color will have a slash (/)
after it followed by the tracer color.
CIRCUIT IDENTIFICATION
All circuits in the diagrams use an alpha/numeric
code to identify the wire and its function. To identify
which circuit code applies to a system, refer to the
Circuit Identification Code Chart. This chart shows
the main circuits only and does not show the second-
ary codes that may apply to some models.
LOCATING A SYSTEM
To locate a system or component in the diagrams,
refer to the alphabetical index at the front of the di-
agrams. Determine the diagram sheet number. Sheet
numbers are located at the lower right or left handcorner of each sheet.Page numbers at the top of
the page do not apply to diagram sheets.
The index identifies the main system and all com-
ponents that relate to that system. There are also
sections of the index that identify specific compo-
nents only (for example modules, lamps, etc.). Refer
to a components name in the index if you are unclear
as to what a system may be called.
Diagram sheets are arranged starting with the bat-
tery and fuses. Then working into charging, starting,
and ignition systems. After this they start at the
front of the vehicle and work to rear. The diagrams
end with connector identification pages.
COMPONENT IDENTIFICATION
When looking for a components location in the vehicle
refer to the Component Identification section index.
This section shows the wire harness routing and the
components location in the vehicle. When using this sec-
tion refer to the wiring diagrams for the general loca-
tion of the component. Then use the component
identification index to locate the proper figure number.
SPLICE LOCATIONS
Splice locations are indicated in the diagrams by a
diamond with a splice circuit code within it (Fig. 5
example 1). If there is more than one splice per cir-
cuit a small box will be connected to it with the
splice number in it (Fig. 5 example 2).
To locate a splice in the wiring harness determine
the splice number from the wiring diagrams then re-
fer to the splice location index. This section shows
the general location of the splice in the harness.
Fig. 2 Secondary Ignition Wiring 4.0L
Fig. 3 Wire Color Code Identification
Fig. 4 Wire Color Code Chart
8W - 2 WIRING DIAGRAMSJ

CONNECTORS
The connectors shown in the diagram sheets are
viewed from the terminal end unless otherwise speci-
fied. For viewing bulkhead, powertrain control module,
and transmission control module connectors refer to the
rear of the wiring diagrams. This area shows major con-
nectors and identifies pin and cavity information.
The connectors shown in the diagrams are identi-
fied in two ways. The first is an actual view of the
connector. This view shows the connector and which
cavity the wire is in.
The second way is with the use of arrows to indicate
the connector. This is done when the connector is to
large to be shown on the diagram page. A box placed
next to the connector identifies the connector and the
cavity the wire is in. In certain instances there may be
more than one connector in the same location. When
this happens the connector identification box will have a
number placed in it. Refer to the rear of the diagrams
for a complete pin out of the connector.
TROUBLESHOOTING WIRING PROBLEMS
When troubleshooting wiring problems there are
six steps which can aid in the procedure. The steps
are listed and explained below.(1) Verify the problem.
(2) Verify any related symptoms. Do this by per-
forming operational checks on components that are
in the same circuit as the problem area. Refer to the
wiring diagrams fuse application chart for circuit
identification.
(3) Analyze the symptoms. Use the wiring dia-
grams to determine what the circuit is doing, where
the problem most likely is occurring and where the
diagnosis will continue.
(4) Isolate the problem area.
(5) Repair the problem.
(6) Verify proper operation. For this step check for
proper operation of all items on the circuit repaired.
Refer to the wiring diagram fuse application chart for
circuit identification.
FUSIBLE LINKS
Vehicle wiring harnesses are equipped with fusible
links to protect against harness damage in the event
of a short in the system. Fusible links are color coded
to indicate wire gauge and size. Refer to the fusible
link chart for color and gauge identification (Fig. 6).
Fig. 5 Wiring Splice Examples
Fig. 6 Fusible Link Chart
JWIRING DIAGRAMS 8W - 3

(10) Spread the strands of the wire apart on each
of the exposed wires (Fig. 7 example 1).
(11) Push the two ends of wire together until the
strands of wire are close to the insulation (Fig. 7 ex-
ample 2).
(12) Twist the wires together (Fig. 7 example 3).
(13) Solder the connection together using rosin
core type solder only.Do not use acid core solder.
(14) Center the heat shrink tubing over the joint
and heat using a heat gun. Heat the joint until the
tubing is tightly sealed and sealant comes out of both
ends of the tubing.
(15) Insert the repaired wire into the connector.
(16) Install the connector locking wedge and recon-
nect the connector to its mating half.
(17) Re-tape the wire harness starting 1-1/2 inches
behind the connector and 2 inches past the repair.(18) Connect battery and test affected systems.
SYMBOLS, FUSES AND ABBREVIATIONS
Various symbols are used throughout the wiring di-
agrams. These symbols can be identified by referring
to the symbol identification chart (Fig. 11).
Certain abbreviations are also used in the dia-
grams. These have been developed in such a way
that there meaning should be clear. For fuse block,
relay bank, and power distribution center informa-
tion refer to the fuse charts and relay bank index.
CAUTION: When replacing a blown fuse it is impor-
tant to replace it with a fuse having the correct am-
perage rating. The use of a fuse with a rating other
than indicated may result in an electrical overload.
If a proper rated fuse continues to blow, it indicates
a problem that should be corrected.
8W - 6 WIRING DIAGRAMSJ