coolant temperature ISUZU TROOPER 1998 Service User Guide

AIR CONDITIONING 1BÐ91
6. Heating Start Timing Control
When the automatic heater/air conditioner is
started, heating is turned on under following
conditions.
·The detected temperature of thermo unit is
136¡F or less.
·The temperature setting signal and the total
signal by each sensor meet the condition of
heating.
When the detected temperature by the coolant
temperature sensor is 136¡F or less the blower
fan motor is set to work at low speed and the
"DEF" mode is selected.
When the detected temperature by the coolant
temperature sensor is 77¡F or more, the blow
mode changes automatic control. And the
blower fan speed is controlled to be lineally up
from "LO" to "MAX HI".7. Cooling Start Timing Control
When the automatic heater/air conditioner is
started, cooling is turned on under following
conditions.
·The in car sensor is 86¡F or more.
·The temperature setting signal and the signals
from each sensor meet the specified condition.
The blower fan speed is set to "LO" for
maximum 7 seconds when cooling start
conditions meet, and then, is controlled to be
lineally up to "MAX HI" by 5.32%/S.
Ignition swich
"ON"
Time
Blower voltage to turn
on the cooling
7 SEC maximum3 SEC
100%
(MAX HI)
33.5%
(LO)5.32%/S
C06RY00001
33.5%
(LO)
2.63%/S
Mode
DEF
Auto
Mode
100%
(MAX HI)
Ignition
switch "ON"
Thermo Unit 58¡C(Gasoline)
52¡C(Diesel) Time
840RY00009

AIR CONDITIONING 1BÐ95
Performance and Movement checklist for Automatic Air Conditioner Related Parts
Start the engine, and when the engine coolant reached 60¡C check performance and movement of the
related parts according the following checklist.
1. Performance Check Using the Manual Switch
Checking ApproachNo.ItemAcceptance criteria
Condition Operation
Blowing
temperature
(check movement
of air mix door)
Airflow volume
(check movement
of the mode door)Set temperature to
25.0¡C.(1) Turn the fan knob
off.
(2) Turn the fan knob
from LOW to HI.(1) The fan shall be stopped, thus
stopping air blow, too.
(2) Airflow volume shall change
from LOW to HI.
Blowing
temperature
(check movement
of the mode door)Set temperature to
25.0¡C.
Set the fan knob to HI.Press the mode switch
to change the blow port
mode sequentially from
the VENT through BI-
LEVEL, FOOT up to
DEF.LED corresponding to each mode
shall be turned on and the blow
port mode shall be switched
smoothly.
The
interior/outside air
switching mode
(check movement
of intake door)Set temperature to
25.0¡C.Turn the LED off using
the interior/outside air
switch (this introduces
the outside air intake
mode). Then, the set
fan knob to HI and
press the
interior/outside switch
to turn on the LED.The LED indication shall be
switched from OFF to ON
accompanying a change in air
blowing sound.
Compressor Set the temperature to
FC. (Outside air
temperature is 0C or
above and interior
temperature at ordinary
temperature.)Press the "OFF" switch.
(1) Press the Auto
switch.
(2) Press the Air
Conditioner switch.(1) As the fan knob is set to the
Auto position, the A/C switch
LED shall come on and the
compressor shall be turned on.
(2) As the A/C LED comes off, the
compressor shall be turned off. Auto switch must be
turned on
(FAN-AUTO
MODE-AUTO)(1) Select FC for the
setup temperature.
(2) Select FH for the
setup temperature.
®Then, select the
MAX Control.(1) Cold air shall be blown out.
(2) Hot air shall be blown out.
1
2
3
4
5

1BÐ118 AIR CONDITIONING
Inspection of the Magnet Clutch System
6VE1 Engine
I-32
C-1C-3I-33
E-3E-19
12345678
9 10111213141516
1
112
123
134
145
156
167
178
189
1910
20
B-19C-25
A 2
B-361
H-14
C-19
25A
BLOWER
MOTOR
C-20
10A
A/C FL-1
80A
MAIN
Heater
Relay
1B-3610
H-13
0.3
B 0.85
W/G0.85
W/R
3.0
W
3.0
L/R
0.5
BR
1.25
B
B-19
BODY-LH3
B-36
4B-36
BATT.(+)
Blower
MotorIntake
Actuator STARTER
RELAY(1)
0.5
LG 0.5
BR0.5
BR
0.5
G/W
0.5
P/G0.5
P/G0.5
G/O
0.5
G/O
PCM
(C3-E15)
31 13
COMP-F/B 70.5
BR
0.5
BR/Y 0.3
G/B0.5
G/B0.5
BR/Y 0.5
BR
Triple
Pressure
Switch
0.5
BR
A
A/C
Thermo Relay
Auto A/C Control Unit
3X-5
16
H-1617H-16
14
I-3218I-33
1X-5
13H-24
12
H-41
2 1
C-25
C-25
4X-5X-5 2
X-57
H-16
A/C
Compressor
Relay
Magnetic
clutch
1X-7
3X-74X-72
X-7
PCM
(C-1-B14)
E-39
1
H-67
H-41
5
H-41
Engine
Coolant
Temperature
Sensor
ENGINE COOLANT
TEMPERATURE GAUGE
0.5
Y/B
0.5
Y/B
0.5
Y/B
E-1911
1
H-61
H-24
I-334
B-36X-5X-7
H-14
1
2
1
2
H-16
H-24
H-13
H-6H-41
12
3412111
362
51
4 123
45 610987654321
22212019181514131211171612345111213141567891018192021221617
6H-41
4321
8765
12 11 10 9
16 15 14 13123 4
567 8
9101112
13 14 15 16
17 18 16 15 1478 6 5
12 13 11 10 94 132
5 6 7 8
15 16 17 18 142 3 41
10 11 12 13 9A1 A2 A3 A4 A5 A6 A7 A8 A9A10 A11 A12 A13 A14 A15 A16B1 B2 B3 B4 B5 B6 B7 B8 B9B10 B11 B12 B13 B14 B15 B16E1 E2 E3 E4 E5 E6 E7 E8 E9E10 E11 E12 E13 E14 E15 E16F1 F2 F3 F4 F5 F6 F7 F8 F9F10 F11 F12 F13 F14 F15 F16
D08RY00182

6A±6
ENGINE MECHANICAL
Rough Engine Idling or Engine Stalling
ConditionPossible causeCorrection
Trouble in fuel injection systemIdle air control valve defectiveReplace
Throttle shutting off incompleteCorrect or replace
Throttle position sensor circuit open
or shortedCorrect or replace
Fuel injector circuits open or shortedCorrect or replace
Fuel injectors damagedReplace
Fuel pump relay defectiveReplace
Mass Airflow Sensor circuit open or
poor connectionsCorrect or replace
Mass Airflow Sensor defectiveReplace
Manifold Absolute Pressure Sensor
circuit open or poor connectionsCorrect or replace
Manifold Absolute Pressure Sensor
defectiveReplace
Engine Coolant Temperature Sensor
circuit open or poor connectionsCorrect or replace
Engine Coolant Temperature Sensor
defectiveReplace
Intake Air Temperature sensor circuit
open or poor connectionsCorrect or replace
Intake Air Temperature sensor
defectiveReplace
Knock Sensor (KS) cable broken or
poor connectionsCorrect or replace
KS defectiveReplace
KS Module circuits open or groundCorrect or replace
KS Module defectiveReplace
Vehicle Speed Sensor circuit open or
shortedCorrect or replace
Vehicle Speed Sensor defectiveReplace
Trouble in emission control systemPowertrain Control Module defectiveReplace
Exhaust Gas Recirculation Valve
circuit open or poor connectionsCorrect or replace
Exhaust Gas Recirculation Valve
faultyReplace
Canister purge valve circuit open or
poor connectionsCorrect or replace
Canister purge valve defectiveReplace
Evaporative Emission Canister
Purge control valve defectiveReplace
Trouble in ignition systemRefer to ªHard Startº

6A±7
ENGINE MECHANICAL
Condition CorrectionPossible cause
OthersEngine lacks compressionRefer to ªHard Startº
Valve incorrectly seatedLap valve
Air Cleaner Filter cloggedReplace filter element
Valve timing incorrectReadjust
Idle air control valve brokenReplace
Fast idle solenoid defectiveReplace
Positive Crankcase Ventilation valve
defective or cloggedReplace
Rough Engine Running
ConditionPossible causeCorrection
Engine misfires periodicallyIgnition coil layer shortedReplace
Spark plugs foulingClean or install hotter type plug
Spark plug(s) insulator nose leakingReplace
Fuel injector(s) defectiveReplace
Powertrain control module faultyReplace
Engine knocks periodicallySpark plugs running too hotInstall colder type spark plugs
Powertrain control module faultyReplace
Engine lacks powerSpark plugs fouledClean
Fuel injectors defectiveReplace
Mass Airflow Sensor or Intake
Airflow Sensor circuit defectiveCorrect or replace
Manifold Absolute Pressure (MAP)
Sensor or Manifold Absolute
Pressure Sensor circuit defectiveCorrect or replace
Engine Coolant Temperature Sensor
or Engine Coolant Temperature
Sensor circuit defectiveCorrect or replace
Powertrain Control Module faultyReplace
Intake Air Temperature Sensor or
Intake Air Temperature Sensor
circuit defectiveCorrect or replace
Throttle Position Sensor or Throttle
Position Sensor circuit defectiveCorrect or replace
Knock Sensor or Knock Sensor
circuits defectiveCorrect or replace
Knock Sensor Module or Knock
Sensor Module circuits defectiveCorrect or replace

6A±9
ENGINE MECHANICAL
Condition CorrectionPossible cause
Hesitation at high speedsPowertrain Control Module defectiveReplace
Throttle Position Sensor cable
broken or poor connectionsCorrect or replace
Throttle Position Sensor defectiveReplace
Engine Coolant Temperature Sensor
circuit open or shortedCorrect or replace
Engine Coolant Temperature Sensor
defectiveReplace
Mass Airflow Sensor circuit open or
poor connectionsCorrect or replace
Mass Airflow Sensor defectiveReplace
MAP Sensor cable broken or poor
connectionsCorrect or replace
MAP Sensor defectiveReplace
IAT Sensor circuit open or poor
connectionsCorrect or replace
IAT Sensor defectiveReplace
KS circuit open or poor connectionsCorrect or replace
KS defectiveReplace
KS Module circuit open or shortedCorrect or replace
KS Module defectiveReplace
Throttle valve not fully openedCheck and correct or replace
Air Cleaner Filter cloggedReplace filter element
Power supply voltage too lowCheck and correct or replace

6A±10
ENGINE MECHANICAL
Engine Lacks Power
ConditionPossible causeCorrection
Trouble in fuel systemFuel Pressure Control Valve not
working normallyReplace
Fuel injector cloggedClean or replace
Fuel pipe cloggedClean
Fuel filter clogged or fouledReplace
Fuel pump drive circuit not working
normallyCorrect or replace
Fuel tank not sufficiently breathing
due to clogged Evaporative
Emission Control System circuitClean or replace
Water in fuel systemClean
Inferior quality fuel in fuel systemUse fuel of specified octane rating
Powertrain Control Module supplied
poor voltageCorrect circuit
Throttle Position Sensor cable
broken or poor connectionsCorrect or replace
Throttle Position Sensor defectiveReplace
Mass Airflow Sensor not working
normallyReplace
Manifold Absolute Pressure Sensor
not working normallyReplace
Intake Air Temperature Sensor not
working normallyReplace
Engine Coolant Temperature Sensor
circuit open or shortedCorrect or replace
Engine Coolant Temperature Sensor
defectiveReplace
Powertrain Control Module defectiveReplace
Trouble in intake or exhaust systemAir Cleaner Filter cloggedReplace filter element
Air duct kinked or flattenedCorrect or replace
Ignition failureÐÐÐÐRefer to Hard Start Troubleshooting
Guide
Heat range of spark plug inadequateInstall spark plugs of adequate heat
range
Ignition coil defectiveReplace

6A±13
ENGINE MECHANICAL
Condition CorrectionPossible cause
Engine knockingPreignition due to use of spark plugs
of inadequate heat rangeInstall Spark Plugs of adequate heat
range
Carbon deposits in combustion
chambersClean
Fuel too low in octane ratingReplace fuel
Wide Open Throttle enrichment
system failureRefer to Section 6E
Selection of transmission gear
incorrectCaution operator of incorrect gear
selection
Engine overheatingRefer to ªEngine Lacks Powerº
OthersWater pump defectiveReplace
Drive belt slippingReplace auto tentioner or drive belt
Abnormal Combustion
ConditionPossible causeCorrection
Trouble in fuel systemFuel pressure control valve defectiveReplace
Fuel filter cloggedReplace
Fuel pump cloggedClean or replace
Fuel tank or fuel pipe cloggedClean or replace
Fuel injector cloggedClean or replace
Fuel pump relay defectiveReplace
Power supply cable for fuel pump
broken or poor connectionsReconnect, correct or replace
Mass Airflow (MAF) sensor circuit
open or defectiveCorrect or replace
MAF Sensor defectiveReplace
Manifold Absolute Pressure Sensor
circuit open or shortedCorrect or replace
Manifold Absolute Pressure Sensor
defectiveReplace
Engine Coolant Temperature (ECT)
Sensor circuit open or shortedCorrect or replace
ECT Sensor defectiveReplace
Throttle Position Sensor adjustment
incorrectReadjust
Throttle Position Sensor defectiveReplace
Throttle Position Sensor connector
poor connectionsReconnect
Vehicle Speed Sensor cable poor
connections or defectiveCorrect or replace
Vehicle Speed Sensor loosely fixedFix tightly
Vehicle Speed Sensor in wrong
contact or defectiveReplace
Powertrain Control Module cable
poor connections or defectiveCorrect or replace

6A±17
ENGINE MECHANICAL
Malfunction Indicator Lamp
The instrument panel ªCHECK ENGINEº Malfunction
Indicator Lamp (MIL) illuminates by self diagnosticsystem when the system checks the starting of engine, or
senses malfunctions.
Condition
Possible causeCorrection
ªCHECK ENGINEº MIL does not
illuminate at the starting of engine
Bulb defectiveReplace
illuminate at the starting of engineMIL circuit openCorrect or replace
Command signal circuit to operate
self diagnostic system shortedCorrect or replace
Engine Control Module (PCM) cable
loosely connected, disconnected or
defectiveCorrect or replace
PCM defectiveReplace
ªCHECK ENGINEº MIL illuminates,
and stays onDeterioration of heated oxygen
sensor internal elementReplace
Heated oxygen sensor connector
terminal improper contactReconnect properly
Heated oxygen sensor lead wire
shortedCorrect
Heated oxygen sensor circuit openCorrect or replace
Deterioration of engine coolant
temperature sensor internal elementReplace
Engine coolant temperature sensor
connector terminal improper contactReconnect properly
Engine coolant temperature sensor
lead wire shortedCorrect
Engine coolant temperature sensor
circuit openCorrect or replace
Throttle position sensor open or
shorted circuitsCorrect or replace
Deterioration of crankshaft position
sensorReplace
Crankshaft position sensor circuit
open or shortedCorrect or replace
Vehicle speed sensor circuit openCorrect or replace
Manifold absolute pressure sensor
circuit open or shortedCorrect or replace
Intake air temperature sensor circuit
open or shortedCorrect or replace
Fuel injector circuit open or shortedCorrect or replace
PCM driver transistor defectiveReplace PCM
Malfunctioning of PCM RAM
(Random Access Memory) or ROM
(Read Only Memory)Replace PCM

6A±18
ENGINE MECHANICAL
Cylinder Head Cover LH
Removal
1. Disconnect battery ground cable.
2. Drain engine coolant from faucet bottom of radiator.
3. Remove engine cover from the dowels on the
common chamber.
F06RW018
4. Remove air cleaner duct assembly (3) and air cleaner
element (4).
130RW001
Legend
(1) Positive Crankcase Ventilation Hose Connector
(2) Intake Air Temperature Sensor
(3) Air Cleaner Duct Assembly
(4) Air Cleaner Element
(5) Mass Air Flow Sensor
NOTE: Disconnect the mass air flow (MAF) sensor
connector, intake air temperature (IAT) sensor connector,
and positive crankcase ventilation (PCV) hose before
hand the air cleaner duct assembly is removed.5. Disconnect following wiring connectors and bonding
cable:

Manifold Absolute Pressure (MAP) sensor

Vacuum Switching Valve (VSV) for Induction Air
Control Valve (IACV) actuator

Ignition coils for left bank

Fuel injectors for left bank

Idle air control (IAC) valve

Throttle position sensor (TPS)

Bonding cable

Others as necessitated
6. Disconnect following vacuum hoses:

Brake master VAC

Canister

VSV for IACV actuator

Duty solenoid valve

PCV
7. Disconnect radiator upper and lower hoses
8. Remove engine harness from the cylinder head
cover.
9. Remove the upper fan guide.
10. Remove cooling fan and clutch assembly.
11. Remove drive belt by pushing down the auto
tensioner using spanner as illustrated.
F06RW019