2002 ISUZU AXIOM Service Repair Manual

HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
1A±111
ConditionPossible causeCorrection
The fan dose not rotate at allÐRefer to Chart A
The fan dose not rotate in the
MAX±HI modeÐRefer to Chart B
The fan dose not rotate in any mode
other than MAX±HIÐRefer to Chart C
The fan dose not stopÐRefer to Chart D
Chart A: Fan Does Not Rotate At All
StepActionValue(s)Ye sNo
1Are the fuse No.F±5, F±6 and No.F±7 normal?
ÐGo to Step 2
Replace the
fuse
2Are the relay No.X±1 and No.C±35 normal?
ÐGo to Step 3
Replace the
relay
3Turn on the ignition switch (the engine is run).
Is the battery voltage applied between the harness side
connector terminal No.C36±1 and ground?
ÐGo to Step 5Go to Step 4
4Repair an open circuit between terminal No.C36±1 and
No.F±5 and F±6 fuse.
Is the action complete?
ÐGo to Step 3Ð
5Is there continuity between the harness side connector
terminal No.C36±2 and ground (No.C±10)?
ÐGo to Step 7Go to Step 6
6Repair an open circuit between terminal No.C36±2 and
ground.
Is the action complete?
ÐÐÐ
7Is the battery voltage applied between the harness side
connector terminal No.C36±2 and No.C36±1?
ÐGo to Step 8Go to Step 9
8Replace the blower motor.
Is the action complete?
ÐVerify repairÐ
9Refer to chart B and C.
Is the action complete?
ÐVerify repairÐ

1A±112
HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
Chart B: Fan Does Not Rotate in MAX HI Mode
StepActionValue(s)Ye sNo
1Is the MAX-HI relay (C±35) normal?
ÐGo to Step 2
Replace the
relay
21. Turn on the ignition switch (the engine is run).
2. Set the fan switch to the MAX-HI.
Is there continuity between the harness side connector
terminal No.C36±2 and No.C35±5?
ÐGo to Step 4Go to Step 3
3Repair an open circuit between terminal No.C36±2 and
No.C35±5.
Is the action complete?
ÐGo to Step 3Ð
4Is there continuity between the harness side connector
terminal No.C35±1 and ground (No.C±10)?
ÐGo to Step 6Go to Step 5
5Repair an open circuit between terminal No.C35±1 and
ground (No.C±10).
Is the action complete?
ÐGo to Step 4Ð
6Is the battery voltage applied between the harness side
connector terminal No.C35±2 and ground?
ÐGo to Step 8Go to Step 7
7Repair an open circuit between terminal No.C35±2 and
No.F±7 fuse.
Is the action complete?
ÐGo to Step 6Ð
8Is the battery voltage applied between the harness side
connector terminal No.I19±2 and ground?
ÐGo to Step 10Go to Step 9
9Repair an open circuit between terminal No.C35±4 and
No.I19±2.
Is the action complete?
ÐVerify repairÐ
10Replace the auto air conditioner control unit.
Is the action complete?
ÐVerify repairÐ

HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
1A±113
Chart C: Fan Does Not Rotate In Any Mode Other Than MAX HI
StepActionValue(s)Ye sNo
1Is the power transistor performance normal? (Refer to
the
later section on ªindividual inspectionº)
ÐGo to Step 2
Replace the
power
transistor
2Is there continuity between the harness side connector
terminal No.C36±2 and No.C34±1, No.C36±2 and
No.I20±17?
ÐGo to Step 4Go to Step 3
3Repair an open circuit between terminal.
No.C36±2 and C34±1
No.C36±2 and I20±17
ÐGo to Step 2Ð
4Is there continuity between the harness side connector
terminal No.C34±3 and ground (No.C±10)?
ÐGo to Step 6Go to Step 5
5Repair an open circuit between terminal No.C34±3 and
ground.
Is the action complete?
ÐGo to Step 4Ð
6Is there continuity between the harness side connector
terminal No.C34±2 and No.I20±19?
ÐGo to Step 8Go to Step 7
7Repair an open circuit between terminal No.C34±2 and
No.I20±19.
Is the action complete?
ÐGo to Step 6Ð
8Replace the auto air conditioner control unit.
Is the action complete?
ÐVerify repairÐ

1A±114
HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
Chart D: Fan Does Not Stop
StepActionValue(s)Ye sNo
11. Disconnect the max high relay, the power transistor
connector C±34 and the auto A/C control unit
connector I±20.
2. Turn on the ignition switch.
Does the blower motor stop?
ÐGo to Step 3Go to Step 2
2Repair a short circuit between connector No.C36±2
and No.C35±5, No.C36±2 and No.C34±1, or
No.C36±2 and I20±17.
Is the action complete?
ÐVerify repairÐ
3Is the max high relay normal? (Refer to the later section
on ªindividual inspectionº.
)ÐGo to Step 4
Replace the
relay
4Reinstall the max high relay.
Does the blower motor start operating?
ÐGo to Step 6Go to Step 5
5Repair a short circuit between connector No.C35±4
and No.I19±2.
Is the action complete?
ÐGo to Step 4Ð
6Is the power transistor normal? (Refer to the later
section on ªindividual inspectionº.
)
ÐGo to Step 7
Replace the
power
transistor
7Reinstall the power transistor.
Does the blower motor start operating?
Ð
Replace the
auto A/C
control unit
Ð

HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
1A±115
Inspection of the Magnetic Clutch System
6VE1 Engine
D08R200037

1A±116
HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
ConditionPossible causeCorrection
Magnetic clutch does not workÐRefer to Chart A
Chart A: Magnetic Clutch Does Not work
StepActionValue(s)Ye sNo
1Is the fuse No.F±7 normal?
ÐGo to Step 2
Replace the
fuse
2Is the relay No.X±2 (compressor relay) No.X±8 (A/C
thermo relay) and No.X±1 (heater relay) normal?
ÐGo to Step 3
Replace the
relay
3Is there continuity between the pressure switch side
connector terminal No.C21±1 and No.C21±2?
ÐGo to Step 5Go to Step 4
4Pressure switch defective or refrigerant pressure
improper.
Pressure switch replaced or refrigerant pressure
adjusted?
ÐGo to Step 3Ð
51. Turn the ignition switch on. (the engine is run.)
2. Turn the air conditioner switch on.
Is the battery voltage applied between the harness side
connector terminal No.E2±1 and the ground?
ÐGo to Step 7Go to Step 6
6Magnetic clutch defective or earth defective.
Magnetic clutch replaced or earth replaced?
ÐGo to Step 5Ð
7Is there continuity between the harness side connector
terminal No.X2±1 and No.E2±1?
ÐGo to Step 9Go to Step 8
8Repair an open circuit between terminal No.X2±1 and
No.E2±1.
Is the action complete?
ÐGo to Step 7Ð
9Is the battery voltage applied between the harness side
connector terminal No.X2±5 and ground, No.X2±2 and
ground?
ÐGo to Step 11Go to Step 10
10Repair an open circuit between terminal No.X2±5 and
fuse No.F±7, No.X2±2 and fuse No.F±7.
Is the action complete?
ÐGo to Step 9Ð
11Is the battery voltage applied between the harness side
connector terminal No.I20±18 and ground?
ÐGo to Step 13Go to Step 12
12Repair an open circuit between terminal No.I20±18 and
No.X2±4.
Is the action complete?
ÐGo to Step 11Ð
13Is the battery voltage applied between the harness side
connector terminal No.C21±2 and ground?
ÐGo to Step 15Go to Step 14
14Repair an open circuit between terminal No.C21±2 and
fuse No.F±7.
Is the action complete?
ÐGo to Step 13Ð
15Is the battery voltage applied between the harness side
connector terminal No.X8±5 and ground, No.X8±2 and
ground?
ÐGo to Step 17Go to Step 16
16Repair an open circuit between terminal No.X8±5 and
No.C21±1, No.X8±2 and fuse No.F±7.
Is the action complete?
ÐGo to Step 15Ð

HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
1A±117
Chart A: Magnetic Clutch Does Not work (Cont'd)
StepNo Ye s Value(s) Action
17Is the battery voltage applied between the harness side
connector terminal No.I19±14 and ground?
ÐGo to Step 19Go to Step 18
18Repair an open circuit between terminal No.X8±3 and
I19±14.
Is the action complete?
ÐGo to Step 17Ð
19Is there continuity between the harness side connector
terminal No.X8±1 and PCM (F45)?
ÐGo to Step 21Go to Step 20
20Repair an open circuit between terminal No.X8±1 and
PCM (F45).
Is the action complete?
ÐGo to Step 19Ð
21Is there continuity between the harness side connector
terminal No.X2±4 and PCM (F4)?
ÐGo to Step 23Go to Step 22
22Repair on open circuit between terminal No.X2±4 and
PCM (F4).
Is the action complete?
ÐGo to Step 21Ð
23Is there continuity between the harness side connector
terminal No.I20±4 and ground?
ÐGo to Step 25Go to Step 24
24Repair an open circuit between terminal No.I20±4 and
PCM (S47).
Is the action complete?
ÐGo to Step 23Ð
251. Connect the connector of PCM.
2. Connect the connector terminal No.I19±14 which is
on the harness side on the auto air conditioner
control unit.
Magnetic clutch works?
Ð
Replace the
auto air
conditioner
control unit
Replace the
PCM
CAUTION: T h e r e a r e conditions which air
conditioner system dose not operate except trouble
as follows.
1. The throttle is griater than 90%.
2. The ignition voltage is below 10.5 volts.
3. The engine speed greater than 4500 RPM for 5
seconds or 5400 RPM.
4. The engine coolant temperature (ECT) is greater
than 125
C (257
F).
5. The intake air temperature (IAT) is less than 5
C
(41
F).
6. The power steering pressure switch signals a
high pressure condition.

1A±118
HEATING, VENTILATION AND AIR CONDITIONING (HVAC)
Individual Inspection
In Car Sensor
1. Disconnect the in car sensor connector (I±17).
2. Measure resistance between the in car sensor side
terminal No.I17±3 and No.I17±4.
C01R200015
Sun Sensor
1. Disconnect the sun sensor connector (I±15).
2. Measure the current value on the sun sensor when
placed it approximately 15 cm away from 60W
incandescent lamp.
D06R200001
Ambient Sensor
1. Disconnect the connector (C±19) on the ambient
sensor.
2. Measure resistance between the ambient sensor side
terminals.
C01R200014