Page 147 of 6020
HEATER AND AIR CONDITIONING 1-113
YES
• Is the electronic thermostat OK?
Open circuit between the engine room
harness connector terminal No. 1 (C-55)
and ground (C-109).
NO YES
• Disconnect the A/C switch.
• Is there battery voltage between the chassis side
harness connector terminal No. 6 (B-57) and ground?
Open circuit between the No. EB-13 fuse
and the chassis side harness connector
No. 6 (B-57)
NO
YES
• Defective ECM Replace electronic thermostat
NO
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ISUZU KB P190 2007
Page 148 of 6020
1-114 HEATER AND AIR CONDITIONING
C24SE
RTW 610XF000501
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Page 149 of 6020

HEATER AND AIR CONDITIONING 1-115
MAGNETIC CLUTCH DOES NOT RUN (C24SE)
Replace
YES
• Are the A/C thermo (X-15), heater & A/C (X-11)
and A/C compressor (X-14) relay OK?
• Are the No. SBF 8 fuse (30A) and the No. EB-13
(10A) fuses OK?
YES
• Is the pressure switch (C-24) OK?
YES
• Are the A/C switch (B-57) and the fan switch (B-13)
OK?
NO
YES
• Is there continuity between the engine harness
connector terminal No.1 (E-2) and the engine room
harness connector terminal No.2 (X-14)?
• Disconnect the A/C compressor relay.
• Turn the ignition switch "ON" (Engine is running)
• A/C switch and fan control knob (fan switch "ON")
NO
Replace
NO
Defective switch or insufficient
refrigerant
NO
NO
Does the magnetic clutch
operate?
YES
Replace
• Disconnect the magnetic clutch connector.
• Is there battery voltage between the engine room
harness connector terminal No.1 (E-2) and ground?
Defective compressor
YESNO
Defective magnetic clutch
• Is the electronic thermostat (C-55) OK?
Replace
NOYES
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Page 150 of 6020

1-116 HEATER AND AIR CONDITIONING
Open circuit between the No. EB-13
fuse and the engine room harness
connector terminal No.1 (X-14).
NO
YES
• Is there battery voltage between the engine room
harness connector terminal No.1 (X-14) and
ground?
YES
• Disconnect the A/C thermo relay.
YES
• Is there continuity between the ECM harness
connector terminal C24SE No. 14 (C-56) and the
engine room harness connector terminal No.4
(X-14)?
Open circuit between the No. EB-13
fuse and the engine room harness
connector terminal No. 3 (X-14).
NO
• Is there battery voltage the engine room harness
connector terminal No.3 (X-14) and ground?
YES
• Is there continuity between the ECM harness
connector terminal C24SE No. 26 (C-56) and the
engine room harness connector terminal No. 1
(X-15)? Open circuit between the ECM
harness connector terminal C24SE
No.14 (C-56) and the engine room
harness connector terminal No. 4 (X-
14).
NO
YES
• Is there battery voltage between the engine room
harness connector terminal No. 2 (X-15) and
ground? Open circuit between the ECM
harness connector terminal C24SE
No. 26 (C-56) and the engine room
harness connector terminal No. 1 (X-
15).
NO
YES
• Is there continuity between the engine room
harness connector terminal No. 3 (X-15) and the
engine room harness connector terminal No. 1 (C-
24).
Open circuit between the No. EB-13
fuse and engine room harness
connector terminal No. 2 (X-15).
NO
• Disconnect the ECM harness connector.
• Disconnect the pressure switch?
Open circuit between the engine harness
connector terminal No.1 (E-2) and the
engine room harness connector terminal
No.2 (X-14).
NO
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Page 151 of 6020

HEATER AND AIR CONDITIONING 1-117
YES
• Disconnect the condenser fan relay connector condenser
fan.
YES
• Is there battery voltage between the engine room
harness connector terminal NO. 3 (C-24) and ground?Open circuit between the condenser fan
relay No.3 (X-10) and engine room harness
connector terminal No. 4 (C-24).
NO
• Is there continuity between the relay terminal No. 3 (X-
10) and engine room harness connector terminal No.4
(C-24)?
YES
Open circuit between the No. EB-13 fuse
and engine room harness connector
terminal No. 3 (C-24).
NO
YES
• Is there continuity between the engine room harness
connector terminal No. 2 (C-55) and the engine room
harness connector terminal No. 2 (C-24)?
Open circuit between the engine room
harness connector terminal No. 4 (X-15)
and the engine room harness connector
terminal No. 1 (C-24).
NO
• Disconnect the pressure switch.
• Is there continuity between the engine room harness
connector terminal No. 4 (X-15) and the engine room
harness connector terminal No. 1 (C-24).
Open circuit between the No. EB-13 fuse
and the engine room harness connector
terminal No. 2 (X-15).
NO
• Connect the A/C thermo relay connector.
• Disconnect the electronic thermostat.
Open circuit between the engine room
harness connector terminal No.3 (X-15)
and the engine room harness connector
terminal No. 1 (C-24).
NO
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ISUZU KB P190 2007
Page 152 of 6020
1-118 HEATER AND AIR CONDITIONING
YES
• Disconnect the A/C switch.
• Is there battery voltage between the chassis side
harness connector terminal No. 6 (B-57) and ground?
Open circuit between the engine room
harness connector terminal No. 2 (C-24)
and the engine room harness connector
terminal No. 2 (C-55).
NO YES
• Is there battery voltage between the engine room
harness connector terminal No. 3 (C-55) and ground?
Open circuit between the No. EB-13 fuse
and the engine room harness connector
terminal No. 3 (C-55).
NO YES
• Is there continuity between the engine room harness
connector terminal No. 1 (C-55) and ground (C-109)?
Open circuit between the engine room
harness connector No. 1 (C-55) and ground
(C-109).
NO
YES
• Is the electronic themostat OK? Open circuit between the No. EB-13 fuse
and the chassis side harness connector
No. 6 (B-57).
NO
YES
• Defective ECM Replace electronic thermostat
NO
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Page 153 of 6020
HEATER AND AIR CONDITIONING 1-119
SPECIAL SERVICE TOOL
ILLUSTRATION PART NO. PART NAME
5-8840-0629-0 (J-39500-A)
5-8840-0630-0
(J-39500-220A)
5-8840-0631-0
(J-39500-220ANZ)
5-8840-4056-0 (J-37872)
Drive plate holder
5-8840-0121-0 (J-33943)
Clutch pulley puller pilot
5-8840-0111-0 (J-8433)
Clutch pulley puller
5-8840-0118-0 (J-33940)
Clutch pulley installer
5-8840-0007-0 (J-8092)
Driver handle
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ISUZU KB P190 2007
Page 832 of 6020

ENGINE MECHANICAL 6A – 27
111R300001
COOLING SYSTEM
Coolant Level
Check the coolant level and replenish the radiator reserve
tank as necessary.
If the coolant level falls below the “MIN” line, carefully
check the cooling system for leakage. Then add enough
coolant to bring the level up to the “MAX” line.
Engine coolant Filling up procedure
1. Make sure that the engine is cool.
Warning:
When the coolant is heated to a high temperature, be
sure not to loosen or remove the rediator cap.
Otherwise you might get scalded by hot vapor or
boiling water.
To open the radiator cap, put a piece of thick cloth on
the cap and loosen the cap slowly to reduce the
pressure when the coolant has become cooler.
2. Open rediator cap pour coolant up to filler neck
3. Pour coolant into reservoir tank up to “MAX” line
4. Tighten radiator cap and start the engine. After idling for 2 to 3 minutes, stop the engine and reopen radiator
cap. If the water level is lower, replenish.
5. After replenish the coolant tighten radiator cap, warm up the engine at about 2000 rpm. Set heater
adjustment to the highest temperature position, and let
the coolant circulate also into heater water system.
6. Check to see the thermometer, continuously idling 5 minutes and stop the engine.
7. W hen the engine has been cooled, check filler neck for water level and replenish if required. Should
extreme shortage of coolant is found, check the
coolant system and reservoir tank hose for leakage.
8. Pour coolant into the reservoir tank up to “MAX” line.
Engine Coolant Total Capacity Lit (U.S / UK gal)
4JA1 / TC 9.4 (2.5 / 2.1)
4JH1TC M/T: 10.1 (2.7 / 2.2)
A/T: 10.0 (2.6 / 2.2)
Mixing Ratio (Anti-Freeze Solution/W ater)
50 %
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