Circuit ISUZU KB P190 2007 Workshop Repair Manual

0A-2 GENERAL INFORMATION
GENERAL REPAIR INSTRUCTIONS
1. Park the vehicle on level ground and chock the front or rear wheels before lifting the vehicle.
2. Raise the vehicle with a jack set against the axle or the frame.
3. Support the vehicle on chassis stands.
4. Use covers on the vehicle body, seats, and floor to prevent damage and/or contamination.
5. Disconnect the grounding cable from the battery before performing service operations.
This will prevent cable damage or burning due to short circuiting.
6. Handle brake fluid and antifreeze solution with great care.
Spilling these liquids on painted surfaces will damage the paint.
7. The use of the proper tool(s) and special tool(s) where specified is essential to efficient, reliable, and safe
service operations.
8. Always use genuine ISUZU replacement parts.
9. Discard used cotter pins, gaskets, O-rings, oil seals, lock washers, and self-locking nuts at disassembly.
Normal function of these parts cannot be guaranteed if they are reused.
10. Prepare new cotter pins, gaskets, O-rings, oil seals, lock washers, and self-locking nuts for installation.
11. Keep the disassembled parts neatly in groups. This will facilitate smooth and correct reassembly.
12. Keep fixing nuts and bolts separate. Fixing nuts and bolts vary in hardness and design according to installation position.
13. Clean all parts before inspection or reassembly.
14. Clean the oil ports and other openings with compressed air to make certain that they are free from dirt and obstructions.
15. Lubricate the rotating and sliding faces of all moving parts with oil or grease before installation.
16. Use the recommended liquid gasket to prevent leakage.
17. Carefully observe all nut and bolt torque specifications.
18. W hen removing or replacing parts that require refrigerant to the discharged from the air conditioning system, be sure to use the Vehicle Refrigerant Recovery and Recycling Equipment (VRRRE) to recover and recycle R134a,
to promote the aim of the protection of the ozone layer covering the earth.
19. Check and recheck your work. No service operation is complete until you have done this.


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ISUZU KB P190 2007

1-30 HEATER AND AIR CONDITIONING
ON-VEHICLE SERVICE
PRECAUTIONS FOR REPLACEMENT OR
REPAIR OF AIR CONDITIONING PARTS
There are certain procedures, practices and precautions that
should be followed when servicing air conditioning systems:
• Keep your work area clean.
• Always wear safety goggle and protective gloves when
working on refrigerant systems.
• Beware of the danger of carbon monoxide fumes caused by
running the engine.
• Beware of discharged refrigerant in enclosed or improperly
ventilated garages.
•
Always disconnect the negative battery cable and discharge
and recover the refrigerant whenever repairing the air
conditioning system.
• W hen discharging and recovering the refrigerant, do not
allow refrigerant to discharge too fast; it will draw
compressor oil out of the system.
• Keep moisture and contaminants out of the system. W hen
disconnecting or removing any lines or parts, use plugs or
caps to close the fittings immediately.
Never remove the caps or plugs until the lines or parts are reconnected or installed.
• W hen disconnecting or reconnecting the lines, use two
wrenches to support the line fitting, to prevent from twisting
or other damage.
• Always install new O-rings whenever a connection is
disassembled.
• Before connecting any hoses or lines, apply new specified
compressor oil to the O-rings.
• W hen removing and replacing any parts which require
discharging the refrigerant circuit, the operations described
in this section must be performed in the following sequence:

1) Using the ACR
4 (HFC-134a Refrigerant Recovery/
Recycling/Recharging/System) or equivalent to
thoroughly discharge and recover the refrigerant.
ACR
4 (115V 60Hz) : 5-8840-0629-0 (J-39500-A)
ACR4 (220-240V 50/60Hz)
: 5-8840-0630-0 (J-39500-220A)
ACR
4 (220-240V 50/60Hz Australian model)
: 5-8840-0631-0 (J-39500-220ANZ)
2) Remove and replace the defective part.
3)
After evacuation, charge the air conditioning system and
check for leaks.


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ISUZU KB P190 2007

1-86 HEATER AND AIR CONDITIONING
BLOWER MOTOR DOES NOT RUN


Replace
YES
• Is No.SBF-6 (30A) (except C24SE) or No.SBF-8
(30A) (C24SE) slow blow fuse OK?
• Is heater & A/C relay (X-11) OK?
YES
• Is resistor OK?
YES
• Is fan control knob (Fan switch) OK?
YES
YES
• Check to see if battery voltage is present at
chassis side connector terminal No.C105-1 is there a
battery voltage?
• Turn the ignition switch "ON" (Engine is running)
• Fan control knob (Fan switch) "ON"
• Is blower motor OK?
YES
Open circuit either between chassis side connector
terminal No.C105-2 and No.C104-3 or No.B13-1 and
body ground No.C-109.
NO
Replace
NO
Replace
NO
NO
Replace control lever
assembly
Replace
NO
NO
Open circuit between
No.SBF-6 (30A) (except
C24SE) or No.SBF-8 (30A)
(C24SE) slow blow fuse and
No.C105-1.


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ISUZU KB P190 2007

HEATER AND AIR CONDITIONING 1-87
BLOWER MOTOR DOES NOT RUN IN CERTAIN POSITION

A 1: (Low)
Blower motor does not
B 2: (Medium Low) Position
run at
C 3: (Medium Hi)

D 4: (High)
* Checkin
g is performed only when in the malfunction
mode.
•
Is resistor OK?
YES
•
Is fan control knob (Fan switch) OK?
YES
Condition:
•
O
pen circuit between chassis side connector
terminal No. C104-2 and No. B13-3
B Condition :
•
O
pen circuit between chassis side connector
terminal No. C104-4 and No. B13-6
C Condition:
•
O
pen circuit between chassis side connector
terminal No. C104-1 and No. B13-5
D Condition:
•
O
pen circuit between chassis side connector
terminal No. C105-2 and No. B13-4
Replace
NO
NO
Replace control leverassembly A


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ISUZU KB P190 2007

1-88 HEATER AND AIR CONDITIONING
BLOWER MOTOR DOES NOT STOP AT “OFF” POSITION

•
Is fan control knob (Fan switch)OK?

YES


Check the circuit between chassis side connector terminals
for short to GND
•
No.


C105-2 and No. C104-3

(or)

•
No

. C105-2 and No. B13-4
(or)

•
No

. C104-1 and No. B13-5
(or)

•
No

. C104-4 and No. B13-6
(or)

•
No

. C104-2 and No. B13-3
NO
Replace control lever assembly



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ISUZU KB P190 2007

1-96 HEATER AND AIR CONDITIONING




Open circuit between the engine room
harness connector terminal No.1 (X-
15).
NOYES
• Is there continuity between the engine room
harness connector terminal No.2 (X-15) and
ground?
YES
• Is there battery voltage between the engine room
harness connector terminal No.3 (X-15) and
ground? Open circuit between the engine room
harness connector terminal No. 2 (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. 2 (C-
24)?
Open circuit between the No. EB-13
fuse and the engine room harness
connector terminal No. 3 (X-15).
NO
• Disconnect the pressure switch.
• Disconnect the condenser fan relay connector
condenser fan.
• Is there battery voltage between the engine room
harness connector terminal No.4 (C-24) and
ground? Open circuit between the condenser
fan relay No. 3 (X-13) and engine
room harness connector terminal No.3
(C-24).
• Is there continuity between the relay terminal
No.3 (X-13)and engine room harness connector
terminal No.3 (C-24)?
Open circuit between the engine room
harness connector terminal No. 5 (X-
15) and the engine room harness
connector terminal No. 2 (C-24).
YES NO
YES NO



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ISUZU KB P190 2007

HEATER AND AIR CONDITIONING 1-97



YES
Open circuit between the No. EB-13
fuse and engine room harness
connector terminal No. 4 (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. 1 (C-24).
NO
YES
• Is there continuity between the engine room
harness connector terminal No.1 (C-55) and the
chassis side harness connector terminal No.5
(B-57) ? or (cooler only) the short connector
terminal No.3 (B-79) and the chassis side
harness connector terminal No.5 (B-57)? 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. 1
(C-24)?
Open circuit between the engine room
harness connector terminal No. 1 (C-
55) or (cooler only) the short
connector No. 3 (B-79) and the
chassis side harness connector
terminal No.5 (B-57). • 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)?
YES NO


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ISUZU KB P190 2007

1-98 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 (C-
109)?
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
• 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

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