Page 134 of 6020
1-100 HEATER AND AIR CONDITIONING
MAGNETIC CLUTCH DOES NOT RUN (4JH1-TC)
Replace
YES
• Are the A/C thermo (X-15) and heater & A/C (X-11)
and A/C compressor (X-14) relay OK?
• Are the No. SBF-6 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-3) 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-3) and ground?
Defective compressor
YESNO
Defective magnetic clutch
• Is the electronic thermostat (C-55) OK?
YES
Replace
NO
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ISUZU KB P190 2007
Page 135 of 6020
HEATER AND AIR CONDITIONING 1-101
Open circuit between the engine
harness connector terminal No.1 (E-3)
and the engine room harness
connector terminal No.2 (X-14).
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 No.38 (C-56) and the engine
room harness connector terminal No.5 (X-14)?
NO
Open circuit between the No. EB-13
fuse and the engine room harness
connector terminal No.1 (X-14).
NO
Open circuit between the engine room
harness connector terminal No.2 (X-
15) and the engine room harness
connector terminal No. 3 (X-14).
NO
• Is there continuity between the engine room
harness connector terminal No.3 (X-14) and No.2
(X-15)?
YES
• Is there continuity between the ECM harness
connector terminal No.33 (C-56) and the engine
room harness connector terminal No.1 (X-15)? Open circuit between the ECM
harness connector terminal No.38 (C-
56) and the engine room harness
connector terminal No. 5 (X-14).
NO
YES
• Is there battery voltage between the engine room
harness connector terminal No.3 (X-15) and
ground? Open circuit between the ECM
harness connector No. 33 (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. 5 (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. 3 (X-15).
NO
• Disconnect the ECM harness connector.
• Disconnect the pressure switch?
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ISUZU KB P190 2007
Page 136 of 6020
1-102 HEATER AND AIR CONDITIONING
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-9) and the engine
room harness connector terminal No.
4 (C-24).
NO
• Is there continuity between the relay terminal
No. 3 (X-9) 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 battery voltage between the engine
room harness connector terminal No.3 (C-55)
and ground? Open circuit between the engine room
harness connector terminal No. 2 (C-
55) and the engine room harness
connector terminal No. 2 (C-24).
NO
YES
• Is there continuity between the engine room
harness connector terminal No.1 (C-55) and
ground (C-109) ? Open circuit between the No. EB-13
fuse and the engine room harness
connector terminal No. 3 (C-55).
NO
• connect the A/C thermo relay connector.
• Disconnect the electronic thermostat.
• 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. 5 (X-
15) and the engine room harness
connector terminal No. 1 (C-24).
NO
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ISUZU KB P190 2007
Page 137 of 6020
HEATER AND AIR CONDITIONING 1-103
YES
• Disconnect the A/C switch.
• Is there battery voltage between the chassis side
harness connector terminal No. 6 (B-57) and ground (C-
109)?
Open circuit between the engine room
harness connector terminal No. 1 (C-55)
and ground (C-109).
NO
YES
• Defective ECM Open circuit between the No. EB-13 fuse
and the chassis side harness connector
No. 6 (B-57).
NO
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ISUZU KB P190 2007
Page 138 of 6020
1-104 HEATER AND AIR CONDITIONING
4JJ1-TC Standard Output, 4JJ1-TC High Output, 4JK1-TC High Output RHD MODEL
RTW 710XF000401
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ISUZU KB P190 2007
Page 139 of 6020
HEATER AND AIR CONDITIONING 1-105
MAGNETIC CLUTCH DOES NOT RUN (4JJ1-TC Standard Output, 4JJ1-TC
High Output, 4JK1-TC High Output RHD MODEL)
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-6 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-3) 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-3) and ground?
Defective compressor
YESNO
Defective magnetic clutch
• Is the electronic thermostat (C-55) OK?
YES
Replace
NO
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ISUZU KB P190 2007
Page 140 of 6020
1-106 HEATER AND AIR CONDITIONING
Open circuit between the engine
harness connector terminal No.1 (E-3)
and the engine room harness
connector terminal No.2 (X-14).
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 No.55 (C-58) and the engine
room harness connector terminal No.5 (X-14)?
NO
Open circuit between the No. EB-13
fuse and the engine room harness
connector terminal No.1 (X-14).
NO
Open circuit between the engine room
harness connector terminal No.3 (X-
14) and the engine room harness
connector terminal No. 1 (X-15).
NO
• Is there continuity between the engine room
harness connector terminal No.3 (X-14) and the
engine room harness connector terminal No.1 (X-
15).
YES
• Is there continuity between the ECM harness
connector terminal No.4 (C-58) and the engine
room harness connector terminal No.1 (X-15)? Open circuit between the ECM
harness connector terminal No.55 (C-
58) and the engine room harness
connector terminal No. 5 (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 No. 4 (C-
58) and the engine room harness
connector terminal No. 1 (X-15).
NO
YES
• Is there continuity between the engine room
harness connector terminal No. 5 (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
• Disconnect the ECM harness connector.
• Disconnect the pressure switch.
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ISUZU KB P190 2007
Page 141 of 6020
HEATER AND AIR CONDITIONING 1-107
YES
• Disconnect the condenser fan relay.
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-9) and the engine
room harness connector terminal No.
4 (C-24).
NO
• Is there continuity between the relay terminal
No. 3 (X-9) 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 battery voltage between the engine
room harness connector terminal No.3 (C-55)
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 continuity between the engine room
harness connector terminal No.1 (C-55) and
ground (C-109) ? or (cooler only) the short
connector terminal No.3 (B-79) and ground (C-
109
)?
Open circuit between the No. EB-13
fuse and the engine room harness
connector terminal No. 3 (C-55).
NO
• connect the A/C thermo relay connector.
• Disconnect the electronic thermostat.
• 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. 5 (X-
15) and the engine room harness
connector terminal No. 1 (C-24).
NO
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ISUZU KB P190 2007
