1998 ISUZU TROOPER electrical system

ENGINE ELECTRICAL 6D1 Ð 3
BATTERY CHARGING
Observe the following safety precautions when
charging the battery:
1. Never attempt to charge the battery when the
fluid level is below the lower level line on the
side of the battery. In this case, the battery
must be replaced.
2. Pay close attention to the battery during the
charging procedure.
Battery charging should be discontinued or the
rate of charge reduced if the battery feels hot to
the touch.
Battery charging should be discontinued or the
rate of charge reduced if the battery begins to
gas or spew electrolyte from the vent holes.
3. In order to more easily view the hydrometer
blue dot or ring, it may be necessary to jiggle or
tilt the battery.
4. Battery temperature can have a great effect on
battery charging capacity.
5. The sealed battery used on this vehicle may be
either quick-charged or slow-charged in the
same manner as other batteries.
Whichever method you decide to use, be sure
that you completely charge the battery. Never
partially charge the battery.
JUMP STARTING
JUMP STARTING WITH AN AUXILIARY
(BOOSTER) BATTERY
CAUTION:
Never push or tow the vehicle in an attempt to
start it. Serious damage to the emission system
as well as other vehicle parts will result.
Treat both the discharged battery and the
booster battery with great care when using
jumper cables. Carefully follow the jump
starting procedure, being careful at all times to
avoid sparking.
WARNING:
Failure to carefully follow the jump starting
procedure could result in the following:
1. Serious personal injury, particulaly to
your eyes.
2. Property damage from a battery explo-
sion, battery acid, or an electrical fire.
3. Damage to the electronic components of
one or both vehicles particularly. Never expose the battery to an open flame or elec-
trical spark. Gas generated by the battery may catch
fire or explode.
Remove any rings, watches, or other jewelry before
working around the battery. Protect your eyes by
wearing an approved set of goggles.
Never allow battery fluid to come in contact with
your eyes or skin.
Never allow battery fluid to come in contact with
fabrics or painted surfaces.
Battery fluid is a highly corrosive acid.
Should battery fluid come in contact with your
eyes, skin, fabric, or a painted surface, immediately
and thoroughly rinse the affected area with clean
tap water.
Never allow metal tools or jumper cables to come
in contact with the positive battery terminal, or any
other metal surface of the vehicle. This will protect
against a short circuit.
Always keep batteries out of the reach of young
children.
JUMP STARTING PROCEDURE
1. Set the vehicle parking brake.
If the vehicle is equipped with an automatic
transmission, place the selector lever in the
ÒPARKÓ position.
If the vehicle is equipped with a manual trans-
mission place the shift lever in the ÒNEUTRALÓ
position.
Turn ÒOFFÓ the ignition.
Turn ÒOFFÓ all lights and any other accessory
requiring electrical power.
2. Look at the built-in hydrometer.
If the indication area of the built-in hydrometer
is completely clear, do not try to jump start.
3. Attach the end of one jumper cable to the posi-
tive terminal of the booster battery.
Attach the other end of the same cable to the
positive terminal of the discharged battery.
Do not allow the vehicles to touch each other.
This will cause a ground connection, effectively
neutralizing the charging procedure.
Be sure that the booster battery has a 12 volt
rating.
4. Attach one end of the remaining cable to the
negative terminal of the booster battery.
Attach the other end of the same cable to a
solid engine ground (such as the A/C com-
pressor bracket or the generator mounting
bracket) of the vehicle with the discharged bat-
tery.
This ground connection must be at least 450
mm (18 in) from the battery of the vehicle
whose battery is being charged.
ON-VEHICLE SERVICE

ENGINE MECHANICAL 6A – 13
VALVE CLEARANCE ADJUSTMENT
1. Install 2.80 mm valve adjuster (shim) first when
reassembling the engine.
Thickness mark faces down.
2. Measure the valve clearance after installing cam
carrier assy with camshafts.
3. Change the adjuster using a special tool when the
clearance is out of tolerance.
Valve Clearance Adjusting Tool: 5-8840-2590-0
VALVE CLEARANCE (When cold condition)
Inlet 0.15 ± 0.05 mm
Exh 0.25 ± 0.05 mm
COMPRESSION PRESSURE
MEASUREMENT
1. Start the engine and allow it to idle until the coolant
temperature reaches 70 – 80°C (158 – 176°F).
2. Remove the following parts.
•Glow plugs
•Fuel cut solenoid connector
•QOS (Quick-On Start System) fuse in the fuse
box.
3. Set the adapter and compression gauge to the No.
1 cylinder glow plug hole.
Compression Gauge
(with Adapter): 5-8840-2008-0
4. Turn the engine over with the starter motor and take
the compression gauge reading.
Compression Pressure at 200 rpm
Standard: 3040 kPa (31 kg/cm
2/441 psi)
Limit: 2160 kPa (22 kg/cm
2/313 psi)
5. Repeat the procedure (Steps 3 and 4) for the
remaining cylinders.
QUICK-ON START 4 SYSTEM
Quick-On Start System Inspection Procedure
1. Disconnect the ECT-sensor connection around the
thermostat outlet pipe.
2. Turn the starter switch to the “ON” position.
If the Quick-On Start 4 System is operating
properly, the glow relay will make a clicking sound
within seven seconds after the starter switch is
turned on.
3. Measure the glow plug terminal voltage with a
circuit tester immediately after turning the starter
switch to the “ON” position.
Glow Plug Terminal Voltage: approx. 12V
NOTE: Electrical power to the quick-on start system will
be cut after the starter has remained in the “ON”
position for twenty seconds.
Turn the starter switch to the “OFF” position and back
to the “ON” position.
This will reset the Quick-On Start 4 System.
014RW150

ENGINE ELECTRICAL 6D – 1
ENGINE ELECTRICAL
CONTENTS
Battery . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6D–1
General Description . . . . . . . . . . . . . . . . 6D–1
Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . 6D–1
On Vehicle Service . . . . . . . . . . . . . . . . . 6D–3
Main Data and Specification . . . . . . . . . . 6D–4
Starting System . . . . . . . . . . . . . . . . . . . . . 6D–5
General Description . . . . . . . . . . . . . . . . 6D–5
On Vehicle Service . . . . . . . . . . . . . . . . . 6D–7
Starter . . . . . . . . . . . . . . . . . . . . . . . . . . 6D–7
Unit Repair . . . . . . . . . . . . . . . . . . . . . . . 6D–8Charging System . . . . . . . . . . . . . . . . . . . . 6D–15
General Description . . . . . . . . . . . . . . . . 6D–15
Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . 6D–16
Unit Repair . . . . . . . . . . . . . . . . . . . . . . . 6D–17
Main Data and Specification . . . . . . . . . . 6D–22
QOS4 Preheating System . . . . . . . . . . . . . . 6D–23
General Description . . . . . . . . . . . . . . . . 6D–23
System Diagram . . . . . . . . . . . . . . . . . . . 6D–23
Inspection of QOS4 System Operation . . 6D–24
BATTERY
GENERAL DESCRIPTION
DIAGNOSIS
There are six battery fluid caps at the top of the battery.
These are covered by a paper label.
The battery is completely sealed except for the six
small vent holes at the side. These vent holes permit
the escape of small amounts of gas generated by the
battery.
This type of battery has the following advantages over
conventional batteries:1. There is no need to add water during the entire
service life of the battery.
2. The battery protects itself against overcharging.
The battery will refuse to accept an excessive
charge.
(A conventional battery will accept an excessive
charge, resulting in gassing and loss of battery
fluid.)
3. The battery is much less vulnerable to self-
discharge than a conventional type battery.
1. VISUAL INSPECTION (Step 1)
Inspect the battery for obvious physical damage, such
as a cracked or broken case, which would permit
electrolyte loss.
Replace the battery if obvious physical damage is
discovered during inspection.
Check for any other physical damage and correct it as
necessary. If not, proceed to Step 2.
2. HYDROMETER CHECK (Step 2)
There is a built-in hydrometer (Charge test indicator) at
the top of the battery. It is designed to be used during
diagnostic procedures.
Before trying to read the hydrometer, carefully clean the
upper battery surface.
If your work area is poorly lit, additional light may be
necessary to read the hydrometer.
a. BLUE RING OR DOT VISIBLE – Go to Step 4.
b. BLUE RING OR DOT NOT VISIBLE – Go to
Step 3.3. FLUID LEVEL CHECK (Step 3)
The fluid level should be between the upper level line
and lower level line on side of the battery.
a. CORRECT FLUID LEVEL – Charge the battery.
b. BELOW LOWER LEVEL – Replace battery.
4. VOLTAGE CHECK (Step 4)
(1) Put voltmeter test leads to battery terminals.
a. VOLTAGE IS 12.4V OR ABOVE – Go to Step 5.
b. VOLTAGE IS UNDER 12.4V – Go to procedure
(2) below.
(2) Determine fast charge amperage from
specification. (See Main Data and Specifications in
this section.)
Fast charge battery for 30 minutes at amperage
rate no higher than specified value.
Take voltage and amperage readings after charge.
a. VOLTAGE IS ABOVE 16V AT BELOW 1/3 OF
AMPERAGE RATE – Replace battery.

ENGINE ELECTRICAL 6D – 3
ON-VEHICLE SERVICE
BATTERY CHARGING
Observe the following safety precautions when
charging the battery:
1. Never attempt to charge the battery when the fluid
level is below the lower level line on the side of the
battery. In this case, the battery must be replaced.
2. Pay close attention to the battery during the
charging procedure.
Battery charging should be discontinued or the rate
of charge reduced if the battery feels hot to the
touch.
Battery charging should be discontinued or the rate
of charge reduced if the battery begins to gas or
spew electrolyte from the vent holes.
3. In order to more easily view the hydrometer blue
dot or ring, it may be necessary to jiggle or tilt the
battery.
4. Battery temperature can have a great effect on
battery charging capacity.
5. The sealed battery used on this vehicle may be
either quick-charged or slow-charged in the same
manner as other batteries.
Whichever method you decide to use, be sure that
you completely charge the battery. Never partially
charge the battery.
JUMP STARTING
JUMP STARTING WITH AN AUXILIARY
(BOOSTER) BATTERY
CAUTION: Never push or tow the vehicle in an
attempt to start it. Serious damage to the emission
system as well as other vehicle parts will result.
Treat both the discharged battery and the booster
battery with great care when using jumper cables.
Carefully follow the jump starting procedure, being
careful at all times to avoid sparking.
WARNING: Failure to carefully follow the jump
starting procedure could result in the following:
1. Serious personal injury, particularly to your
eyes.
2. Property damage from a battery explosion,
battery acid, or an electrical fire.
3. Damage to the electronic components of one or
both vehicles.
Never expose the battery to an open flame or electrical
spark. Gas generated by the battery may catch fire or
explode. Remove any rings, watches, or other jewelry
before working around the battery. Protect your eyes by
wearing an approved set of goggles.
Never allow battery fluid to come in contact with your
eyes or skin.
Never allow battery fluid to come in contact with fabrics
or painted surfaces.
Battery fluid is a highly corrosive acid.Should battery fluid come in contact with your eyes,
skin, fabric, or a painted surface, immediately and
thoroughly rinse the affected area with clean tap water.
Never allow metal tools or jumper cables to come in
contact with the positive battery terminal, or any other
metal surface of the vehicle. This will protect against a
short circuit.
Always keep batteries out of the reach of young
children.
JUMP STARTING PROCEDURE
1. Set the vehicle parking brake.
If the vehicle is equipped with an automatic
transmission, place the selector lever in the “PARK”
position.
If the vehicle is equipped with a manual
transmission place the shift lever in the “NEUTRAL”
position.
Turn “OFF” the ignition.
Turn “OFF” all lights and any other accessory
requiring electrical power.
2. Look at the built-in hydrometer.
If the indication area of the built-in hydrometer is
completely clear, do not try to jump start.
3. Attach the end of one jumper cable to the positive
terminal of the booster battery.
Attach the other end of the same cable to the
positive terminal of the discharged battery.
Do not allow the vehicles to touch each other.
This will cause a ground connection, effectively
neutralizing the charging procedure.
Be sure that the booster battery has a 12 volt rating.
4. Attach one end of the remaining cable to the
negative terminal of the booster battery.
Attach the other end of the same cable to a solid
engine ground (such as the A/C compressor
bracket or the generator mounting bracket) of the
vehicle with the discharged battery.
This ground connection must be at least 450 mm
(18 in) from the battery of the vehicle whose battery
is being charged.
WARNING: Never attach the end of the jumper
cable directly to the negative terminal of the dead
battery.
5. Start the engine of the vehicle with the good battery.
Make sure that all unnecessary electrical
accessories have been turned “OFF”.
6. Start the engine of the vehicle with the dead battery.
7. To remove the jumper cables, follow the above
directions in the reverse order.
Be sure to first disconnect the negative cable from
the vehicle with the discharged battery.

ENGINE ELECTRICAL 6D – 5
STARTING SYTEM
GENERAL DESCRIPTION
STARTING CIRCUIT
The cranking system consists of a battery, starter, starter switch, starter relay, etc. and these main
components are connected as shown in the illustration.
“S”
“B”
“M”
Battery
5
4
32 IG1ST
B2
B1
1
76
P
NN
Legend
(1) Inhibitor Switch
(2) Starter Switch
(3) Battery(4) Magnetic Switch
(5) Pinion Clutch
(6) Starter Motor
(7) Starter Relay
065RW039
STARTER
The starting system employs a magnetic type reduction
starter in which the motor shaft is also used as a pinion
shaft. When the starter switch is turned on, the contacts
of the magnetic switch are closed, and the armature
rotates. At the same time, the plunger is activated, and
the pinion is pushed forward by the shift lever to mesh
with ring gear.Then, the ring gear runs to start the engine. When the
engine starts and the starter switch is turned off, the
plunger returns, the pinion is disengaged from the ring
gear, and the armature stops rotation. When the engine
speed is higher than the pinion, the pinion idles, so that
the armature is not driven.

ENGINE ELECTRICAL 6D – 15
CHARGING SYSTEM
GENERAL DESCRIPTION
GENERATOR
CHARGING CIRCUIT
The charging system is the IC integral regulator
charging system and its main components are
connected as shown in Figure.
The regulator is a solid state type and it is mounted
along with the brush holder assembly inside the
generator installed on the rear end cover.The generator does not require particular maintenance
such as voltage adjustment. The rectifier connected to
the stator coil has nine diodes to transform A.C. voltage
into D.C. voltage. This D.C. voltage is connected to the
output terminal of generator.
A06RW001
Condenser
GeneratorStator Coil
IC RegulatorStarter
SW
Rotor Coil
Battery
P F
EBS LRelay B
S
L
QOS
065R200028

6D – 16 ENGINE ELECTRICAL
DIAGNOSIS
GENERAL ON-VEHICLE INSPECTION
The operating condition of the charging system is
indicated by the charge warning lamp. The warning
lamp comes on when the starter swtich is turned to
“ON” position. The charging system operates normallyif the lamp goes off when the engine starts. If the
warning lamp shows abnormality or if undercharged or
overcharged battery condition is suspected, perform
diagnosis by checking the charging system as follows:
Condenser
GeneratorStator Coil
IC RegulatorStarter
SW
Rotor Coil
Battery
P F
EBS LRelay B
S
L
QOS
065R200028
1. Check visually the belt and wiring connector.
2. With the engine in stop status, turn the starter
switch to “ON” position and observe the warning
lamp.
1) If lamp does not come on:
Disconnect wiring connector from generator,
and ground terminal “L” on connector side.
2) If lamp comes on:
Repair or replace the generator.

ENGINE ELECTRICAL 6D – 23
QOS4 PREHEATING SYSTEM
GENERAL DESCRIPTION
QOS4 preheating system features a quick-on glow plug
with thermometer control of the glowing time and the
afterglow time function.
The system consists of the ECM, indicator lamp, ECT
sensor, vehicle speed sensor, relay and temperature
self-control type glow plugs.With the employment of the ECT sensor, the glow time
changes according to the engine coolant temperature,
thus allowing optimum starting conditions to be
obtained.
The after glow time function is controlled by ECM.
NOTE:
Refer to DTC P0380 and P0381 of 6E section.
SYSTEM DIAGRAM
+
-KEY
50A
ECM
50A
GLOW
50A
2
WHT/
RED
0.5
BLK/
BLU
ECM J1-15 3
WHT/
RED
3
RED/
BLKMAIN
80A
8BLK/RED
Glow
Relay
GLOW PLUG 4
BATTHeater & A/C
Relay
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