1987 MITSUBISHI MONTERO Wiring

Service Manual
MONTERO
1987 : Volume 2
FOREWORD
This Service Manual has been prepared with the
latest service information available at the time of
publication. It is subdivided into various group
categories and each section contains diagnosis,
disassembly, repair, and installation procedures
along with complete specifications and tightening
references. Use of this manual will aid in properly
performing any servicing necessary to maintain or
restore the high levels of performance and reliability
designed into these outstanding vehicles.
WE SUPPORT
VOLUNTARY TECHNICIAN
CERTIFICATION THROUGH
MITSUBISHI MOTOR SALES OF AMERICA. Inc.
Mitsubishi Motors corporation reserves the right to make changes in
design or to make additions to or improvements in its products without
imposing any obligations upon itself to install them on its products
previously manufactured.
I
GROUP/SECTION INDEX ‘kme-.
INTRODUCTION ..............................
Electrical ...........................................
Electrical System Parts
Location .........................................
Relays, Control Units, Sensors,
Fuses, Groundings
Inspection of Harness
Connector ......................................
Wiring Harness .............................
Charging System ..........................
Starting System ............................
Ignition System .............................
Meters and Gauges ......................
Lighting System .............................
Wiper and Washer System ..........
Horn ...............................................
Accessory ......................................
Audio System ................................
Back Door Window Defogger ......
Automatic Free-wheeling Hub
Indicator System ..........................
Heaters and Air-conditioning .........
Heaters ..........................................
Air-conditioning ............................
**, For Engine Chassis & Body refer to
0 1986 Mitsubishi Motors Corporation Printed in Japan

INTRODUCTION - Precautions Before Service 9
nm (in.)
so0059
PARTS
When replacing parts, use MITSUBISHI genuine parts.
VEHICLE WVASHING
If high-pressure car-washing equipment or steam car-washing
equipment is used to wash the vehicle, be sure to maintain the
spray nozzle at a distance of at least 300 mm (1 1.8 in.) from
any plastic parts and all opening parts (doors, luggage
compartment, etc.).
SERVICING THE ELECTRICAL SYSTEM
When servicing the electrical system, disconnect the negative
cable terminal from the battery.
Caution
Before connecting or disconnecting the negative cable, be
sure to turn off the ignition switch and the lighting switch.
(If this is not done, there is the possibility of semiconductor
parts being damaged.)
WIRING HARNESSES
1. Secure the wiring harnesses by using clamps so that there
is no slack. However, for any harness which passes to the
engine or other vibrating parts of the vehicle, allow some
slack within a range that does not allow the engine
vibrations to cause the harness to come into contact with
any of the surrounding parts. Then secure the harness by
using a clamp.
In addition, if a mounting indication mark (yellow tape) is
on a harness, secure the indication mark in the specified
location.
2. If any section of a wiring harness contacts the edge of a
part, or a corner, wrap the section of the harness with tape
or something similar in order to protect it from damage.
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INTRODUCTION - Precautions Before Service 11
I
OOY63:
oOY58S IOA 15A
1 Permissible current 1
Nominal
size
0.3 mm2 AWG22 5A
05mm’ AWG 20
AWG18 ~ zi 13A
0.85 mm2 17A
1.25 mm2 AWG 16 12A 22A
2.0 mm2 AWG14 I 16A 30A
ELECTRICAL COMPONENTS
1. When installing any of the vehicle parts, be careful not to
pinch or damage any of the wiring harnesses.
2. Sensors, relays, etc., are sensitive to strong impacts.
Handle them with care so that they are not dropped or
mishandled.
3. The electronic parts used for relays, etc., are sensitive to
heat, If any service which causes a temperature of 80°C
(176°F) or more is performed, remove the part or parts in
question before carrying out the service.
FUSES AND FUSIBLE LINKS
1. If a blown-out fuse is to be replaced, be sure to use only a
fuse of the specified capacity. If a fuse of a capacity larger
than that specified is used, parts may be damaged and the
circuit may not be protected adequately.
Caution
If a fuse is blown-out, be sure to eliminate the cause of
the problem before installing a new fuse.
2 If additional optional equipment is to be installed in the
vehicle, follow the procedure listed in the appropriate
instruction manual; however, be sure to pay careful
attention to the following points:
(1) In order to avoid overloading the wiring, take the
electrical current load of the optional equipment into
consideration, and determine the appropriate wire size.
(2) Where possible, route the wiring through the existing
harnesses.
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INTRODUCTION - Precautions Before Service 13
IKITE ON INSTALLATION OF RADIO EQUIPMW&
The computers of the electronic control system has been
designed so that external radio waves will not interfere with
their operation.
However, if antenna or cable of amateur transceiver etc. is
routed near the computers, it may affect the operation of the
computers, even if the output of the transceiver is no more
than 25W.
To protect each of the computers from interference by
transmitter (hum, transceiver, etc.), the following should be
observed.
1. Install the antenna on the roof.
2. Because radio waves are emitted from the coaxial cable of
the antenna, keep it 200 mm (8 in.) away from the
computers and the wiring harness. If the cable must cross
the wiring harness, route it so that it runs at right angles to
the wiring harness.
3. The antenna and the cable should be well matched, and
the standing-wave ratio* should be kept low.
4. A transmitter having a large output should not be installed
in the vehicle.
5. After installation of transmitter, run the engine at idle, emit
radio waves from the transmitter and make sure that the
engine is not affected.
High-frequency power supply If an antenna and a cable having different impedances are
connected, the input impedance Zi will vary in accordance
with the length of the cable and the frequency of the
transmitter, and the voltage distribution will also vary in
accordance with the location.
The ratio between this maximum voltage and minimum
voltage is called the standing-wave ratio. It can also be
represented by the ratio between the impedances of the
antenna and the cable.
The amount of radio waves emitted from the cable increases
as the standing-wave ratio increases, and this increases the
possibility of the electronic components being adversely
affected.
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8-1
ELECTRICAL
CONTENTS
NOBAA-
ACCESSORY ......................................................
188
Cigarette Lighter ............................................
,190
Clock ...............................................................
,191
AUDIO SYSTEM ................................................
.192
AUTOMATIC FREE-WHEELING HUB
INDICATOR SYSTEM ........................................
208
Automatic Free-wheeling Hub
Indicator Control Unit
..................................... ,216
Pulse Generator ..............................................
215
BACK DOOR WINDOW DEFOGGER
................ .203
Defogger switch ............................................
,206
Printed Heater Lines
...................................... ,207
CHARGING SYSTEM .........................................
71
Alternator ........................................................
83
Service Adjustment Procedures
..................... 77
Battery Charging ........................................
82
Inspection of Battery ..................................
81
Output Current Test ...................................
78
Regulated Voltage Test ..............................
79
Voltage Drop Test of Alternator Output
Wire ............................................................
77
ELECTRICAL SYSTEM PARTS LOCATION
...... 2
Diode ...............................................................
5
Fusible Link and Fuse
..................................... 6
Grounding .......................................................
7
Relay and Control Unit ....................................
2
Sensor .............................................................
4
HORN ..................................................................
184
Horn Switch
.................................................... 187
IGNITION SYSTEM ............................................
105
Ignition Switch
................................................ 122
Ignition System ...............................................
1 14
Service Adjustment Procedures
.................... .l 1 1
Checking Ignition System
..........................
11 1
Checking Ignition Timing
...........................
11 1
Spark Plug Cable Test
................................
1 12
Spark Plug Test
.......................................... 1 12 INSPECTION OF HARNESS CONNECTOR ...... 9
Check for Improper Engagement of
Terminal .......................................................... 9
Continuity and Voltage Test for Connector .... 9
Engaging and Disengaging of Connector
Terminal ..........................................................
9
LIGHTING SYSTEM ........................................... 143
Column Switch
................................ .
.............. .I59
Dimmer Control Switch
................................. .I62
Hazard Warning Switch
................................. .I61
Headlight ........................................................ ,158
Service Adjustment Procedures
.................... .I57
Headlight Aiming .......................................
157
METERS AND GAUGES .................................... 123
Service Adjustment Procedures
.................... .I30
Fuel Gauge Simple Test ................................. .I31
Fuel Gauge Unit Inspection ........................... .I31
Oil Pressure Gauge Simple Test
.................... .I32
Oil Pressure Gauge Unit Simple Test
............ ,132
Speedometer Inspection
............................... .I30
Tachometer Inspection .................................. ,130
Voltage Meter Simple Test
............................ .I33
Water Temperature Gauge Simple Test
....... ..I3 1
Water Temperature Gauge Unit Inspection
. ..I3 2
STARTING SYSTEM .......................................... 91
Starter Motor ............ ....................................... 97
WIPER AND WASHER SYSTEM
....................... .163
WIRING HARNESS ............................................ 13
Centralized Junction ....................................... 69
Circuit Diagram ............................................... 34
Configuration Diagram .................................... 27
How to Read Wiring Diagrams ....................... 20
Troubleshooting .............................................. 13

WIRING HARNESS - Troubleshooting 8-13
WIRING HARNESS
TROUBLESHOOTING NO8DAAA
The most important point in troubleshooting is to determine “Probable Causes”. Once the probable causes are
determined, parts to be checked can be limited to those associated with such probable causes. Therefore, unnec-
essary checks can be eliminated. The determination of the probable causes must be based on a theory and be
supported by facts and must not be based on intuition only.
TROUBLESHOOTING STEPS
If an attempt is made to solve a problem without going through correct steps for troubleshooting, the problem
symptoms could become more complicated, resulting in failure to determine the causes correctly and making
incorrect repairs. The four steps below should be followed in troubleshooting.
1 1 Observe the
1 problems. symptom carefully. Check if there are also other
1 Observation of Problem Symptoms
b
0,
2 Determination of Probable Causes
In determining the probable causes, it is necessary to check the
wiring diagram to understand the circuit as a system. Knowledge
of switches, relays and other parts is necessary for accurate de-
termination. The causes of similar problems in the past must be
taken into account.
Checking of Parts Associated with Troubleshooting is carried out by making step by step checks until
the true cause is found. Always go through the procedures con-
sidering what check is to be made where for the best results.
14 1 Repair and Confirmation
After the problems are corrected, be sure to check that the sys-
1 been caused by the repair, tem operates correctly Also check that new problems have not
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8-14 WIRING HARNESS - Troubleshooting
1680222
Changeover knob 1680224
1680225 1
1680226
INSPECTION
1. Visual and aural checks
Check relay operation, blower motor rotation, light illumina-
tion, etc. visually or aurally. The flow of current is invisible but
can be checked by the operation of the parts.
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2. Simple checks
For example, if a headlight does not come on and a faulty fuse
or poor grounding is suspected, replace the fuse with a new
one or ground the light to the body by a jumper wire to deter-
mine which part is responsible for the problem.
3. Checking with instruments
Use an appropriate instrument in an adequate range and read
the indication correctly. You must have sufficient knowledge
and experience to handle instruments correctly.
INSPECTION INSTRUMENTS
In inspection, make use of the following instruments.
1. Test lamps
A test lamp consists of a 12 V bulb and lead wires. It is used
to check voltages or shortcircuits.
2. Self-power test lamp
A self-power test lamp consists of a bulb, battery and lead
wires connected in series. It is used to check continuity or
grounding.
,.!‘?i,
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WIRING HARNESS - Troubleshooting 8-15
1660227
Black lead wire
Ground y
1680228
Normal open (NO) type
OFF
ax
Current does not flow ON
Current flows
Normal close (NC) type
OFF
l-2
Current flows ON
-op--
IX
Current does not flow
1680229
pm I 3. Jumper wire
A jumper wire is used to close an open circuit. Never use one
to connect a power supply directly to a load.
4. Voltmeter
A voltmeter is used to measure the circuit voltage. Normally,
the positive (red lead) probe is applied to the point of voltage
measurement and the negative (black lead) probe to the body
ground.
5. Ohmmeter
An ohmmeter is used to.check continuity or measure resis-
tance of a switch or coil. If the measuring range has been
changed, the zero point must be adjusted before measure-
ment.
CHECKING SWITCHES In a circuit diagram, a switch is represented by a symbol and in the
idle state.
1. Normal open or normal close switch
Switches are classified into those which make the circuit open
and those which make the circuit closed when off.
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