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.
_. r.
; ST6 Revision
INTRODUCTION - Towing and Hoisting
HOISTING
POST TYPE
15
Special care should be taken when raising the vehicle on a
frame contact type hoist. The hoist must be equipped with the
proper adapters in order to support the vehicle at the proper
locations. (See next page)
Conventional hydraulic hoists may be used after determining
that the adapter plates will make firm contact with the side
frame.
FLOOR JACK
A regular floor jack may be used under the front crossmember
or rear axle housing.
Caution
1. A floor jack must never be used on any part of the
underbody.
2. Do not attempt to raise one entire side of the vehicle by
placing a jack midway between front and rear wheels.
This practice may result in permanent damage to the
body.
EMERGENCY JACKING
Jack receptacles are located at the No. 2 crossmember and
rear axle housing to accept the jack supplied with the vehicle
for emergency road service. Always block the opposite wheels
and jack only on a level surface.
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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
CHARGING SYSTEM -Specifications
SPECIFICATIONS
GENERAL SPECIFICATIONS
ALTERNATOR NOOEB-B
Type
Model No.
Part No.
Rated output
VIA
Voltage regulator Items Specifications
~--
Battery voltage sensing
A2T03477
MD1 10318
12150
Electronic built-in type
BAlTERY
Items
Type
1
Ampere hours (5 HR) Ah
Cranking rating [at - 178°C (O”F)] A
Reserve capacity min. Specifications
55824R (S)-MF
36
420
75
NOTES
1. CRANKING RATING is the current a battery can deliver for 30 seconds and maintain a terminal voltage of 7.2 or
greater at a specified temperature.
2. RESERVE CAPACITY RATING is the amount of time a battery can deliver 25 A and maintain a minimum terminal
voltage of 10.5 at 26.7”C (80°F).
SERVICE SPECIFICATIONS NOBEC-
Items
Standard values
Regulated voltage V
Ambient temp. at voltage regulator
- 20°C ( - 4°F)
20°C (68°F)
60°C (140°F)
80°C (176°F)
Slip ring O.D. mm (in.)
Field coil resistance R
Limit
Output current A
Slip ring O.D. mm (in.) 14.2-15.4
13.9-14.9
13.4-14.6
13.1-14.5
23 (.906)
3.1
Min. 35
22.2 (.874) Specifications
[ STB Revision
CHARGING SYSTEM - Service Adjustment Procedures 8-77
SERVICE ADJUSTMENT PROCEDUREswmAB
lEL15I
INSPECTION OF THE CHARGING SYSTEM
VOLTAGE DROP TEST OF ALTERNATOR OUTPUT WIRE
This test judges whether or not the wiring (including the fusible
link) between the alternator B terminal and the battery (+) terminal
is sound by the voltage drop method.
Preparation
(1) Turn the ignition switch to “OFF”.
(2) Disconnect the battery ground cable.
(3) Disconnect the alternator output lead from the alternator “B”
terminal.
(4) Connect a DC ammeter (0 to 100 A) in series to the “B”
terminal and the disconnected output lead. Connect the (+)
lead of the ammeter to the “B” terminal and the (-) lead to
the disconnected output wire.
NOTE
Use of a clamp type ammeter that can measure current with-
out disconnecting the harness is preferred. The reason is that
when checking a vehicles that has a low output current due to
poor connection of the alternator “B” terminal, such poor con-
nection is corrected as the “B” terminal is loosened and a test
ammeter is connected in its place and as a result, causes for
the trouble may not be determined.
(5) Connect a digital voltmeter between the alternator “B” termi-
nal and battery (+) terminal. Connect the (+) lead wire of the
voltmeter to the “B” terminal and the (-) lead wire to the
battery (+) terminal.
(6) Connect the battery ground cable.
(7) Leave the hood open.
Test
(1) Start the engine.
(2) Turn on or off the headlights and small lights and adjust the
engine speed so that the ammeter reads 20 A and read off the
voltmeter indication under this condition.
Result
(1) It is okay if the voltmeter indicates the standard value. ’
Standard value : 0.2 V max.
(2) If the voltmeter indicates a value that is larger than the stan-
dard value, poor wiring is suspected, in which case check the
wiring from the alternator “B” terminal to fusible link to bat-
tery (+) terminal. Check for loose connection, color change
due to overheated harness, etc. and correct them before test-
ing again.
(3) Upon completion of the test, set the engine speed at idle. Turn
off the lights and turn off the ignition switch.
(4) Disconnect the battery ground cable.
(5) Disconnect the ammeter and voltmeter that have been con-
nected for the test purpose.
(6) Connect the alternator output wire to the alternator “B” ter-
minal.
(7) Connect the battery ground cable.
( STB Revision
8-78 CHARGING SYSTEM - Service Adiustment Procedures
80A
n
Relay with diode
Voltmeter
Ammeter Iad
176
OUTPUT CURRENT TEST
This test judges whether or not the alternator gives an output
current that is equivalent to the nominal output.
Preparation
(1) Prior to the test, check the following items and correct as
necessary.
(a) Check the battery installed in the vehicle to ensure that it
is in sound state*. The battery checking method is de-
scribed in “BATTERY”.
NOTE
*The battery that is used to test the output current should
be one that has been rather discharged. With a fully
charged battery, the test may not be conducted correctly
due to an insufficient load.
(b) Check tension of the alternator drive belt. The belt tension
check method is described in “GROUP 7 COOLING -
Service Adjustment Procedures”.
(2) Turn off the ignition switch.
(3) Disconnect the battery ground cable.
(4) Disconnect the alternator output wire from the alternator “B”
terminal.
(5) Connect a DC ammeter (0 to 100 A) in series between the “B”
terminal and the disconnected output wire. Connect the (+)
lead of the ammeter to the “B” terminal and connect the (-)
lead wire to the disconnected output wire.
NOTE
Tighten each connection by bolt and nut securely as a heavy
current will flow. Do not relay on clips.
(6) Connect a voltmeter (0 to 20 V) between the “B” terminal and
ground. Connect the (+) lead wire to the alternator “B” ter-
minal and (-) lead wire to a sound ground.
(7) Set the engine tachometer and connect the battery ground
cable.
(8) Leave the engine hood open.
Test
(1) Check to see that the voltmeter reads the same value as the
battery voltage.
If the voltmeter reads 0 V, an open circuit in the wire between
the alternator “B” terminal and battery (-) terminal, a blown
fusible link or poor grounding is suspected.
(2) Turn on the headlight switch and start the engine.
(3) Set the headlight at high beam and the heater blower switch
at HIGH, quickly increase the engine speed to 2500 rpm and
read the maximum output current value indicated by the am-
meter.
NOTE
After the engine start up, the charging current quickly drops.
therefore, above operation must be done quickly to read max-
imum current value correctly.
[ STB Revision
--I
CHARGING SYSTEM - Service Adjustment Procedures 8-79
Result
(1) The ammeter reading must be higher than the limit value. If it
is lower but the alternator output wire is normal, remove the
alternator from the vehicle and check it.
Limit value : 31 A min.
Caution
1. The nominal output current value is shown on the
nameplate affixed to the alternator body.
2. The output current value changes with the electrical
load and the temperature of the alternator itself.
Therefore, the nominal output current may not be ob-
tained if the vehicle electrical load at the time of test is
small. In such a case, keep the headlights on to cause
discharge of the battery or use lights of another vehi-
cle as a load to increase the electrical load. The nom-
inal output current may not be obtained if the temper-
ature of the alternator itself or abmient temperature is
too high. In such a case, reduce the temperature be-
fore testing again.
(2) Upon completion of the output current test, lower the engine
speed to the idle speed and turn off the ignition switch.
(3) Disconnect the battery ground cable.
(4) Remove the test ammeter and voltmeter and the engine ta-
chometer.
(5) connect the alternator output wire to the alternator “B” ter-
minal.
(6) Connect the battery ground cable.
REGULATED VOLTAGE TEST
The purpose of this test is to check that the electronic voltage
regulator controls the voltage correctly.
Preparation
(1) Prior to the test, check the following items and correct if nec-
essary.
(a) Check the battery installed on the vehicle to see that it is
fully charged. For battery checking method, see “BAT-
TERY”.
(b) Check the alternator drive belt tension. For belt tension
check, see “GROUP 7 COOLING - Service Adjustment
Procedures”.
(2) Turn the ignition switch to “OFF”.
(3) Disconnect the battery ground cable.
(4) Connect a digital voltmeter between the “S” terminal of the
alternator and ground. Connect the (+) lead of the voltmeter to
the “S” terminal of the alternator, inserting from the wire side
of the 2-way connector and connect the (-1 lead to sound
ground or battery (-) terminal.
1 ST6 Revision
8-80 CHARGING SYSTEM - Service Adjustment Procedures
Ignition
switch Alternator
Voltmeter
I
lid-hi! @ Ammeter e Load
6EK52
(5) Disconnect the alternator output wire from the alternator “B”
terminal.
(6) Connect a DC ammeter (0 to 100 A) in series between the “B”
terminal and the disconnected output wire. Connect the (+I
lead of the ammeter to the “B” terminal and connect the (-1
lead wire to the disconnected output wire.
(7) Set the engine tachometer and connect the battery ground
cable.
Test
(1) Turn on the ignition switch and-check that the voltmeter indi-
cates the following value.
Voltage : Battery voltage
If it reads 0 V, there is an open circuit in the wire between the
alternator “S” terminal and the battery (+) or the fusible link
is blown.
(2) Start the engine. Keep all lights and accessories off.
(3) Run the engine at a speed of about 2500 rpm and read the
voltmeter when the alternator output current drops to 10 A or
less.
Result
(1) If the voltmeter reading agrees with the value listed in the
regulating voltage table below, the voltage regulator is func-
tioning correctly. If the reading is other than the standard
value, the voltage regulator or the alternator is faulty.
Regulating voltage table
Voltage regulator ambient Regulating voltage V
temperature “C (“F)
-20 (-4) 14.2-15.4
20 (68) 13.9-14.9
60 (140) 13.4-14.6
80 (176) 13.1-14.5
1 STB Revision