heater ISUZU TROOPER 1998 Service Repair Manual

ABBREVIATIONS CHARTS
LIST OF AUTOMOTIVE ABBREVIATIONS WHICH MAY BE USED IN THIS MANUAL
A Ð Ampere(s)
ABS Ð Antilock Brake System
A/C Ð Air Conditioning
ACCEL Ð Accelerator
ACC Ð Accessary
Adj Ð Adjust
A/F Ð Air Fuel Ratio
AIR Ð Air Injection Reaction System
ALDL Ð Assembly Line Diagnostic Link
Alt Ð Altitude
AMP Ð Ampere(s)
ANT Ð Antenna
APS Ð Absolute Pressure Sensor
ASM Ð Assembly
A/T Ð Automatic Transmission/Transaxle
ATDC Ð After Top Dead Center
Auth Ð Authority
Auto Ð Automatic
BARO Ð Barometic
Bat Ð Battery
Bat+ Ð Battery Positive Terminal
Bbl Ð Barrel
BCM Ð Body Control Module
BHP Ð Brake Horsepower
BP Ð Back Pressure
BTDC Ð Before Top Dead Center
¡C ÐDegrees Celsius
Cat. Conv. Ð Catalytic Converter
cc Ð Cubic Centimeter
CCC Ð Computer Command Control
CCOT Ð Cycling Clutch Orifice Tube
CCP Ð Controlled Canister Purge
CID Ð Cubic Inch Displacement
CL Ð Closed Loop
CLCC Ð Closed Loop Carburetor Control
CO Ð Carbon Monoxide
Coax Ð Coaxial
Conn Ð Connector
Conv Ð Converter
CP Ð Canister Purge
CPS Ð Central Power Supply
Crank Ð Crankshaft
CTS Ð Coolant Temperature Sensor
Cu.In. Ð Cubic Inch
CV Ð Constant Velocity
Cyl Ð Cylinder(s)
C
3I Ð Computer Controlled Coil Ignition
DBM Ð Dual Bed Monolith
Diff Ð Differential
DIS Ð Direct Ignition System
Dist ÐDistributor
DOHC Ð Double Overhead Camshaft
DVM Ð Digital Voltmeter (10 meg.)
DVOM Ð Digital Volt Ohmmeter
DVDV Ð Differential Vacuum Delay Valve
EAC ÐElectric Air Control
EAS Ð Electric Air Switching
EBCM Ð Electronic Brake Control Module
ECC Ð Electronic Climate Control
ECM Ð Electronic Control Module
ECU Ð Electronic Control Unit
Ð Engine Calibration Unit (PROM)
EECS Ð Evaporative Emission Control System
EFE Ð Early Fuel Evaporation
EFI Ð Electronic Fuel Injection
EGR Ð Exhaust Gas Recirculation
EGR/TVS Ð Exhaust Gas Recirculation/Thermostatic
Vacuum Switch
ELC Ð Electronic Level Control
ESC Ð Electronic Spark Control
EST Ð Electronic Spark Control
ETR Ð Electronically Tuned Receiver
EVRV Ð Electronic Vacuum Regulator Valve (EGR)
Exh Ð Exhaust
¡F Ð Degrees Fahrenheit
FF Ð Front Drive Front Engine
FL Ð Fusible Link
FLW Ð Fusible Link Wire
FRT ÐFront
FWD Ð Front Wheel Drive
4WD Ð Four Wheel Drive
4x4 Ð Four Wheel Drive
4 A/T Ð Four Speed Automatic Transmission/Transaxle
Gal Ð Gallon
Gen Ð Generator
Gov Ð Governor
g Ð Gram
Harn Ð Harness
HC Ð Hydrocarbons
HD ÐHeavy Duty
HEI Ð High Energy Ignition
Hg Ð Mercury
HiAlt Ð High Altitude
HVAC Ð Heater-Vent-Air Conditioning
IAC Ð Idle Air Control
IC Ð Integrated Circuit
ID Ð Identification
Ð Inside Diameter
IDI Ð Integrated Direct Ignition
IGN Ð Ignition
ILC Ð Idle Load Compensator
INJ ÐInjection
IP Ð Instrument Panel
IPC Ð Instrument Panel Cluster
INT Ð Intake
J/B Ð Junction Block
km Ð Kilometers
km/h Ð Kilometer per Hour
kPa Ð KiloPascals
KV Ð Kilovolts (thousands of volts)
KW Ð Kilowatts
0AÐ12 GENERAL INFORMATION

SERVICE INFORMATION 00 Ð 3
TROUBLESHOOTING
CONTENTS
PAGE
Circuit Diagram.........................................................00Ð 4
Heating Cycle Troubleshooting............................................00Ð16
Fan Control Knob (Fan Switch)............................................00Ð17
Blower Motor Does Not Run............................................00Ð18
Blower Motor Does Not Run In Certain Position............................00Ð19
Blower Motor Does Not Stop at ÒOFFÓ Position............................00Ð19
Ceramic Heater.........................................................00Ð20
Ceramic Heater Does Not Operate.......................................00Ð21
Ceramic Heater Does Not Stop..........................................00Ð22
Air Conditioning Cycle Troubleshooting.....................................00Ð23
Checking Refrigerant System with Manifold Gauge.........................00Ð24
Magnetic Clutch........................................................00Ð27
6VD1/6VE1 Engine....................................................00Ð27
4JG2 Engine.........................................................00Ð31
4JX1 Engine..........................................................00Ð34
Condenser Fan..........................................................00Ð37
Condenser Fan Does Not Run...........................................00Ð38
Condenser Fan Does Not Stop..........................................00Ð39
Compressor Troubleshooting.............................................00Ð40
Individual Inspection.....................................................00Ð41

00 Ð 4 SERVICE INFORMATION
CIRCUIT DIAGRAM
6VD1/6VE1 (RHD)
0.5 LG
0.5 LG
B -1 BODY-RH
BODY-LH
FRAME
ENG.5B
BODY
8B / R
8 B
+
_
P - 6
30B
P - 1
P - 5
P - 10
P - 7
P - 2
FL-1
80A MAINFL-4
30A CONDENSER FAN
F-6
15A RR COOLER
I-232
I-236 A/C SW
BLOWER
MOTOR
0.3 G/Y
I-42 I-42
I-421 3
216
0.5 LG
1
5W
B-190.5 BR
0.5 BR
0.5 P/G H-24 H-5113 1
H-167
H-16
2 L/R
I-41
I-18
I-18
I-18
I-18 1.25 L/O
1.25 L/Y
0.85 L/W 3
36
5
2 4
1 6
FAN SW HEATER BEZEL
ILLUMINATION
I-23 I-23
I-18
I-183
5
4
10.3 R/G0.85 G/R
ILLUMINATION
CONTROLLER (3) RELAY ; TAIL (4)
H-201
2 B
2BLOWER
RESISTOR
I-41
I-41
I-41
I-41
2L/B
2 B
1.25B
M
B-52
1B-5
B-361
B-36
B-36 B-362
34
I-23
10.85W/G
3L/R 3LC-19
25A BLOWER
0.3B
ELECTRONIC
THERMOSTAT
5W 3W
0.5 BR
1.25 L/O
0.5 LG/Y
0.3 G/Y 0.3 G/Y RELAY ;
HEATER AND
A/C
C-20 10A
AIR CON.
0.5 BR 0.5 BR
RELAY;STARTER (1)
5W
H-14
16
H-26
2L/B
2
H-20
H-1310
0.3 G/Y
0.5 LG
D08RY00128

00 Ð 6 SERVICE INFORMATION
6VD1/6VE1-(LHD)
0.5 LG
H - 2614
B - 2 BODY-LH
BODY-RH
FRAME
ENG.5B
BODY
8B / R
8 B
+
_
P - 6
30B
P - 1
P - 5
P - 10
P - 7
P - 2
FL-1
80A MAIN
I - 232
I - 23
I - 236
1A/C SW
BLOWER
MOTOR
0.3 G/Y
I-42 I-42
I-421 3
221 0.5LG
H-141
5W
B-190.5 BR
B
OFF ST
IG2
ACCSTARTER SWIG1
B2 1
4
2
5WFL-2
50A KEY SW
H-142
3W/B
B-11
0.5 BR
0.5 P/G H - 9
H - 51 19 1
H-1617
H-16 0.5LG
0.5 LG
0.5 LG
0.3G/Y
2 L/R
I-41
I - 18
I - 18
I - 18
I - 18 1.25 L/O
1.25 L/Y
0.85 L/W 3
36
5
2 4
1 6
FAN SW HEATER BEZEL
ILLUMINATION
I - 23 I - 23
I - 18
I - 183
5
4
10.5 R/G0.85 G/R
ILLUMINATION
CONTROLLER (3) FUSE F-12
H - 4815
2 B
2BLOWER
RESISTOR
I-41
I-41
I-41
I-41
2L/B
2 B
0.3G/Y
1.25B
M
B - 51
2
C-11 10A
AUDIO(ACC),MIRROR
B - 5
B-361
B-36
B-36 B-362
34
3L/B
0.5O/G
3L/R 3LC-19
25A BLOWER
0.5B
ELECTRONIC
THERMOSTAT
5W 3W
3W/B
3W/B
0.3 G/Y
1
RELAY ;
HEATER AND
A/C
C-20 10A
AIR CON.
0.5 BR
0.5 BR
B - 11B - 11
FL-4
30A CONDENSER FAN
F-1
15A RR COOLER1.25 L/O
0.5LG/Y
0.3 G/Y
D08RY00130

00 Ð 8 SERVICE INFORMATION
4JG2 (RHD)
C-69
FENDER-LHB-1 BODY-RH
BODY-LH
FRAME
ENG.5B
BODY
8B / R
8 B
+
_
P - 6
30B
P - 1
P - 5
P - 10
P - 7
P - 2
FL-1
80A MAINFL-4 30A
CONDENSER FAN
F-6 10A
RR COOLER
1
2 I-232
I-23
I-236
1A/C SW
BLOWER
MOTOR
0.5G/O
I-42 I-42
I-421 3
216
0.5
G/W 0.5 LG
C-25
C-25
0.5LGH-141
5W
B-190.5 BR
0.5BR
X-5 X-5
X-5 X-5
34 RELAY ;
A/C THERMO1
2
0.5 P/G 0.5 P/G
H-41100.5
G/W0.5
G/W
0.5 BR0.5
BR0.5
LG
PRESSURE SW
(CONDENSER) H-2413
0.5 LG
H-16 0.5LG
0.3GY
H-416
H-51
E-31
0.5 G/O
2L/R
I-41
I-18
I-18
I-18
I-18 1.25L/O
1.25L/Y
0.85L/W 3
36
5
2 4
1 6
FAN SW HEATER BEZEL
ILLUMINATION
I-23 I-23
I-18
I-18 3
5
4
10.3 R/G0.85 G/R
ILLUMINATION
CONTROLLER (3)RELAY ; TAIL (4)
H-201 2
BLOWER
RESISTOR
I-41
I-41
I-41
I-41
2L/B
2 B
1.25B
M
B-52
1B-5
B-361
B-36
B-36 B-362
34
3L/R 3LC-19
25A BLOWERRELAY ;
HEATER AND
A/C
0.3B
ELECTRONIC
THERMOSTAT
MAGNETIC CLUTCH
0.5G/O
5W 3W
0.5 BR 1.25 L/O
0.5 LG/Y
2B
C-20 10A
AIR CON.
0.5BR
7H-16
0.3G/Y
0.3G/Y0.3G/Y5W
0.85W/G
RELAY ; CHARGE (1)
H-1310
2
H-202L/B
VSV; FICD
C-69
2 1
0.5G/O 0.5 G/O
C-167
0.5 B
H-2616
H-514
H-511
D08RY00124

00 Ð 10 SERVICE INFORMATION
4JG2 (LHD)
0.5 LG
B - 2 BODY-LH
BODY-RH
FRAME
ENG.5B
BODY
8B / R
8 B
+
_
P - 6
30B
P - 1
P - 5
P - 10
P - 7
P - 2
FL-1
80A MAIN
I - 232
I - 23
I - 236
1A/C SW
BLOWER
MOTOR
0.3 G/Y
I - 42 I - 42
I - 421 3
221
0.5 LG
0.5LG
H-141
5W
B-190.5 BR
B
OFF ST
IG2
ACCSTARTER SWIG1
B2 1
4
2
5WFL-2
50A KEY SW
H-142
3W/B
B-11
0.5 P/G 19
H-1617
H - 161
H - 51 14
H - 26
0.5LG
0.5 LG
2 L/R
I - 41
I - 18
I - 18
I - 18
I - 18 1.25 L/O
1.25 L/Y
0.85 L/W 3
36
5
2 4
1 6
FAN SW HEATER BEZEL
ILLUMINATION
I - 23 I - 23
I - 18
I - 183
5
4
10.5 R/G0.85 G/R
ILLUMINATION
CONTROLLER (3) FUSE F-12
H - 4815
2 B
2BLOWER
RESISTOR
I - 41
I - 41
I - 41
I - 41
2L/B 2L/B
2 B
0.3G/Y1.25B
M
B - 51
2
C-11 10A
AUDIO(ACC),MIRROR
B - 5
4 H - 48
B-361
B-36
B-36 B-362
34
3L/B
0.5O/G
3L/R 3LC-19
25A BLOWER
0.5B
ELECTRONIC
THERMOSTAT
5W 3W
3W/B
3W/B
0.3 G/Y
1
RELAY ;
HEATER AND
A/C
C-20 10A
AIR CON.
0.5 BR
0.5 BR
0.5 BR
B - 11B - 11
FL-4
30A CONDENSER FAN
F-1
15A RR COOLER1.25 L/O
0.5LG/Y
H - 9
D08RY00126

00 Ð 12 SERVICE INFORMATION
4JX1 (RHD)
B-2 BODY-RH
BODY-LH
5B
8B / R
8 B
+
_
P - 6
BODY
30B
P - 1
P - 5
P - 10
P - 7
ENG.
FRAME
P - 2
FL-1
80A MAIN
I-232
I-23
I-236
1A/C SW
BLOWER
MOTORI-42 I-42
I-421 3
216
0.5 LG 0.5 LG0.5 LG
0.5LG1
2
C-25
C-25
H-141
5W
B-19
0.5BR
X-5 X-5
X-5 X-5
34 A/C THERMO
RELAY12
0.5 P/G 0.5 P/GPRESSURE SW
(CONDENSER)THRMO SW
RELAYH-16
E-271
2L/R
I-41
I-18
I-18
I-18
I-18 1.25L/O
1.25L/Y
0.85L/W 3
36
5
2 4
1 6
FAN SW HEATER BEZEL
ILLUMINATION
I-23 I-23
I-18
I-18 3
5
4
10.3 R/G0.85 G/R
TAIL RELAY (4)
H-201
2BLOWER
RESISTOR
I-41
I-41
I-41
I-41
2L/B
2 B
0.3G/Y
1.25B
M
B-52
1B-5
B-361
B-36
B-36 B-362
343L/R 3L
C-19
25A BLOWERHEATER &
A/C RELAY
0.3B
ELECTRONIC
THERMOSTAT
MAGNETIC
CLUTCH
5W 3W
X-12 X-12
X-12 X-12
34 12
B-44
B-441
H-1511
2
0.5
G/W 0.3
G/YECM
(JI-31)
0.5
Y/G
B-491
B-49
2
0.3G/Y
DIODE
FULL HOT
SW
H-1315
CERAMIC
HEATER
B-48
B-482 1
CERAMIC HEATER
RELAY
2B
0.5G/B FL-3
40A C/HEATER
3W/L
2B
3W/G 3W/G
0.5BR
C-20 10A
AIR CON.
0.5BR
0.5 BR7H-16
0.3G/Y
0.3G/Y0.3G/Y5W
0.85W/G
CHARGE
RELAY(1)
H-1310
2
H-202L/B
0.5G/O 0.5G/O 0.5G/O
0.5G/O
H-268
0.5 G/W
0.5 G/Y 0.5 G/B
ECM
(J1-23)
H-4112
0.5 G/W
H-417
H-62
H-174
H-41 5
X-21 X-21
X-21 X-21
43 21H-2413H-2616
ILLUMINATION
CONTROLLER
D08RY00132

00 Ð 14 SERVICE INFORMATION
4JX1 (LHD)
B-2 BODY-LH
BODY-RH
5B
8B / R
8 B
+
_
P - 6
BODY
30B
P - 1
P - 5
P - 10
P - 7
ENG.
FRAME
P - 2
FL-1
80A MAIN
I-232
I-23
I-236
1A/C SW
BLOWER
MOTORI-42 I-42
I-421 3
216
0.5 LG 0.5 LG0.5 LG
0.5LG1
2
C-25
C-25
H-141
5W
B-19
0.5BR
X-5 X-5
X-5 X-5
34 A/C THERMO
RELAYTHERMO
SW
RELAY
12
0.5 P/G 0.5 P/GPRESSURE SW
(CONDENSER)H-13
E-271
2L/R
I-41
I-18
I-18
I-18
I-18 1.25L/O
1.25L/Y
0.85L/W 3
36
5
2 4
1 6
FAN SW HEATER BEZEL
ILLUMINATION
I-23 I-23
I-18
I-18 3
5
4
10.3 R/G0.85 G/R
TAIL RELAY (4)
H-4815
2BLOWER
RESISTOR
I-41
I-41
I-41
I-41
2L/B
2 B
0.3G/Y
1.25B
M
B-51
2B-5
B-361
B-36
B-36 B-362
343L/R 3L
C-19
25A BLOWERHEATER &
A/C RELAY
0.5B
ELECTRONIC
THERMOSTAT
MAGNETIC
CLUTCH
5W 3W
X-12 X-12
X-12 X-12
34 12
B-44
B-441
H-1214
2
0.3
G/W ECM
(JI-31)
0.5
Y/G
B-491
B-49
2
0.3G/Y
DIODE
FULL HOT
SW
H-135
CERAMIC
HEATER
B-48
B-48
2 1
CERAMIC HEATER
RELAY
2B
0.5G/B FL-3
40A C/HEATER
3W/L
2B
3W/G 3W/G
0.5BR
C-20 10A
AIR CON.
0.5BR
0.5 BR17H-16
0.3G/Y
0.3G/Y0.3G/Y5W
0.5O/G
STARTER SW
(ACC)
4
H-482L/B
0.5G/O 0.5G/O 0.5G/O
0.5G/O
H-2610
0.5 G/W
0.5 G/Y 0.5 G/B
ECM
(J1-23)
H-4112
0.5 G/W
H-417
H-62
H-174
H-41 5
X-21 X-21
X-21 X-21
43 21H-919H-2614
ILLUMINATION
CONTROLLER
D08RY00134

00 Ð 16 SERVICE INFORMATION
TROUBLE POSSIBLE CAUSE CORRECTION
HEATING CYCLE TROUBLESHOOTING
No heating or
Insufficient heating.·Refer to ÒFAN CONTROL KNOB (FAN
SWITCH)Ó Troubleshooting.
·Check the engine coolant temperature
after warming up the engine and check
the thermostat. Replace as necessary.
·Add engine coolant as required.
·Check if the water hose to the heater
core is clogged, collapsed or twisted.
Repair or replace as necessary.
·Check water pump function. Repair or
replace as necessary.
·Clean or replace as necessary.
·Repair the temperature control link unit
or mode doors.
·Repair or adjust the control cables.
·Repair or replace as necessary.
·Refer to ÒCERAMIC HEATERÓ
Troubleshooting.
·Repair.
·Repair.
·Repair.
·Adjust. 1. Blower motor does not run, or
runs improperly.
2. Engine coolant temperature is
low.
3. Insufficient engine coolant.
4. Circulation volume of engine
coolant is insufficient.
5. Heater core clogged or
collapsed.
6. The heater core is not provided
with air sent from the blower
motor.
7. Duct connections defective or
unsealing.
8. Ceramic heater defective.
1. Cable attaching clip is not
correct.
2. Link unit of heater unit or
blower assembly defective.
1. Link unit of heater unit or
blower assembly defective
2. Control cable is not adjusted. Control knob moves
but mode door does
not operate.
The mode door
cannot be set to the
mode selected.

SERVICE INFORMATION 00 Ð 17
FAN CONTROL KNOB (FAN SWITCH)
Current flows to the blower motor through the
Heater & A/C relay (B-36) to activate the rotation of
the blower motor by turning ÒONÓ the fan controlknob (fan switch). Blower motor speed is controlled
in stages by the resistor, by operating the switch
from ÒLOWÓ to ÒHIGH.Ó
12
34
B-36B-1B-2
1234561
2123
45 6
I-41B-5I-18
1
2
B-36RELAY;
HEATER & ACC-19
25A
BLOWER
2
3
6
4
1
6
3
5
2
1
MBLOWER
MOTOR2
1
RHD
OFF
B-5B-5
I-18
BLOWER
RESISTOR FAN SW.
I-41
B-1
B-2(LHD) BODY-RH (RHD) BODY-LH
D08RY00167