ISUZU TROOPER 1998 Service Workshop Manual

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

SERVICE INFORMATION 00 Ð 13
D08RY00133
ECM
(J2-11)
0.5 L/P 0.5 L/P
I-25
I-25
3
I-25 2
I-25 6
I-25
5
4
1H-1614
0.3R/G0.85G/R 0.85G/R
ILLUMINATION
CONTROLLER TAIL RELAY(4)
ENGINE
WARMING
SW
1.25B 0.5B
C-74C-741 2THERMO SWH-919
0.5G/W 0.5G/W
0.5 L/P
0.5G/B
H-265
H-4216
H-52
0.5B
H-1615

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

SERVICE INFORMATION 00 Ð 15
D08RY00135
ECM
(J2-11)
0.5 L/P
I-25
I-25
3
I-25 2
I-25 6
I-25
5
4
1H-166
0.3R/G0.85G/R 0.85G/R
ILLUMINATION
CONTROLLER TAIL RELAY(4)
ENGINE
WARMING
SW
1.25B 0.5B
C-74C-741 2THERMO SWH-2417
0.5G/W 0.5G/W
0.5 L/P
0.5G/B
H-2516
H-4216
H-52
0.5B
H-1615

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

00 Ð 18 SERVICE INFORMATION
BLOWER MOTOR DOES NOT RUN
·IS NO. C-19 (25A) FUSE OK?
·IS BLOWER RELAY (B-36) OK?
YESNO
REPLACE
NO
REPLACE
NO
REPLACE
NO
REPLACE CONTROL LEVER ASSEMBLY
NO
REPLACE
NO
OPEN CIRCUIT BETWEEN NO. C-19
(25A) FUSE AND NO. B5-1 (NO. B5-2;
RHD)
YES
·IS RESISTOR OK?
YES
·IS FAN CONTROL KNOB (FAN SWITCH) OK?
YES
·IS BLOWER MOTOR OK?
YES
·TURN THE IGNITION SWITCH ÒONÓ (ENGINE IS
RUNNING)
·FAN CONTROL KNOB (FAN SWITCH) ÒONÓ
·CHECK TO SEE IF BATTERY VOLTAGE IS PRESENT
AT CHASSIS SIDE CONNECTOR TERMINAL NO. B5-1
(NO. B5-2; RHD)
YES
POOR GROUND OR OPEN CIRCUIT EITHER BETWEEN
CHASSIS SIDE CONNECTOR TERMINAL NO. B5-2
(NO. B5-1; RHD) AND NO. I-41-2 OR NO. I18-1 AND BODY
GROUND NO. B-2 (NO. B-1; RHD)

SERVICE INFORMATION 00 Ð 19
BLOWER MOTOR DOES NOT RUN IN CERTAIN
POSITION
A1 : (LOW)
BLOWER MOTOR DOES
B2 : (MEDIUM LOW)
NOT RUN AT
C3 : (MEDIUM HI) POSITION
D4 : (HIGH)
* CHECKING IS PERFORMED ONLY WHEN IN
THE MALFUNCTION MODE.
·IS RESISTOR OK?
YES
·IS FAN CONTROL KNOB (FAN SWITCH) OK?
YES
ACONDITION:
·OPEN CIRCUIT BETWEEN CHASSIS SIDE CONNECTOR
TERMINAL NO. I41-1 AND NO. I18-2
BCONDITION:
·OPEN CIRCUIT BETWEEN CHASSIS SIDE CONNECTOR
TERMINAL NO. I41-4 AND NO. I18-5
CCONDITION:
·OPEN CIRCUIT BETWEEN CHASSIS SIDE CONNECTOR
TERMINAL NO. I41-6 AND NO. I18-3
DCONDITION:
·OPEN CIRCUIT BETWEEN CHASSIS SIDE CONNECTOR
TERMINAL NO. I41-3 AND NO. I18-6
NO
REPLACE
NO
REPLACE CONTROL LEVER
ASSEMBLY
BLOWER MOTOR DOES NOT STOP AT ÒOFFÓ
POSITION
·IS FAN CONTROL KNOB (FAN SWITCH) OK?
YES
SHORT CIRCUIT BETWEEN CHASSIS SIDE
CONNECTOR TERMINAL
·NO. B5-2 (NO. B5-1 : RHD) AND NO. I41-2
(OR)
·NO. I41-3 AND NO. I18-6
(OR)
·NO. I41-6 AND NO. I18-3
(OR)
·NO. I41-4 AND NO. I18-5
(OR)
·NO. I41-1 AND NO. I18-2
NO
REPLACE CONTROL LEVER
ASSEMBLY

00 Ð 20 SERVICE INFORMATION
CERAMIC HEATER
When the fan control knob (fan switch) turns on
with the temperature control knob set to ÒFULL
HOTÓ (full hot switch ÒONÓ), the ceramic heater in
the heater unit turns on and the blow temperature
goes up. When the ceramic heater turns on, FICDstarts to operate at the same time. When either one
of the fan switch, the full hot switch or the thermo
switch (which turns on when the coolant tempera-
ture gets below 80°C (176°F) turns off, the ceramic
heater also turns off.
FL-3
40A
C/HEATER
RELAY;
HEATER A/CECM
(J1-23)
24
13
C-20
10A
A/C
FL-1
80A
MAIN
B-18B-1
B-36
1
3
X-12
2
4
1
3
X-21
2
4
1
2
1
2
4
13
24
1
1
2CERAMIC
HEATER
FAN SW.
B-19
B-48
I-18
B-44
B-49
RELAY;
THERMO
SW
RELAY;
CERAMIC
HEATER
DIODE
FULL HOT
SW.
B-1
B-48
1
21
22112
B-49
I-18
213
5 4612
34
B-36X-12X-21
1234
B-44
(RHD)
B-2(LHD)
B-2
D08RWD66

SERVICE INFORMATION 00 Ð 21
CERAMIC HEATER DOES NOT OPERATE
·ARE NO. FL-3 (40A) AND NO. C-20 (10A) OK?
YESNO
REPLACE
REPLACE
REPLACE
REPLACE
·ARE A/C AND CERAMIC HEATER RELAYS OK?
YESNO
·ARE BLOWER MOTOR AND FAN SW. OK?
YESNO
·IS FULL HOT SW. OK?
·DOES TEMP. CONTROL LINK (HEATER UNIT)
OPERATE CORRECTLY?
YESNO
REPLACE·TURN THE IGNITION SW. ÒONÓ (ENGINE IS RUNNING)·CERAMIC HEATER ÒONÓ
·CHECK TO SEE IF BATTERY VOLTAGE IS PRESENT AT
CHASSIS SIDE CONNECTOR TERMINAL NO. B48-1
YESNO
OPEN CIRCUIT·CHECK TO SEE IF BATTERY VOLTAGE IS PRESENT AT
CHASSIS SIDE CONNECTOR TERMINAL NO. B48-2
YESNO
CERAMIC HEATER DEFECTIVE·CHECK THE CERAMIC HEATER OR CERAMIC HEATER-
RELATED HARNESS FOR A POOR GROUND AND REPAIR
IT AS NECESSARY
YESNO
·DOES CONTROL LEVER CABLE OPERATE CORRECTLY?·IS THERMO RELAY OK?
YESNO
NOYES
ADJUST OR REPLACEREPAIR OR REPLACE
TEMP. CONTROL UNIT