2007 ISUZU KB P190 Circuit

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

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

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

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

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

1-108 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. 1 (C-55) or
(cooler only) the short connector No. 3 (B-
79) and ground (C-109).
NO YES
• Is there continuity between the engine room harness
connector (cooler only) terminal No. 4 (C-55) and the
chassis side harness connector terminal No. 11 (B-57)?
Open circuit between the engine room
harness connector (cooler only) terminal
No. 4 (C-55) and the chassis side harness
connector terminal No. 11 (B-57).
NO YES
• Is there battery voltage between the chassis side
harness connector terminal No. 10 (B-57) and ground?
Open circuit between the chassis side
harness connector No. 1 (B-79) and the
chassis side harness connector terminal
No. 10 (B-57).
NO
YES
• Is the electronic thermostat 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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ISUZU KB P190 2007

HEATER AND AIR CONDITIONING 1-111




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 (X-
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

1-112 HEATER AND AIR CONDITIONING



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)? 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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TO MODEL INDEX
ISUZU KB P190 2007