2001 INFINITI QX4 IDX

Air Mix Door Control SpecificationNBHA0059S03
RHA137G
RHA849E
COMPONENT DESCRIPTIONNBHA0060The air mix door motor is attached to the heater unit. It rotates so
that the air mix door is opened or closed to a position set by the
auto amplifier. Motor rotation is then conveyed through a shaft and
the air mix door position is then fed back to the auto amplifier by
PBR built-in air mix door motor.
RHA504G
SHA522EA
CONTROL LINKAGE ADJUSTMENTNBHA0099Air Mix Door (Water Cock)NBHA0099S011. Install air mix door motor on heater unit and connect it to main
harness.
2. Set up code No. 41 in Self-diagnosis STEP 4. Refer to HA-44.
3. Move air mix door lever by hand and hold it in full cold posi-
tion.
4. Attach air mix door lever to rod holder.
5. Make sure air mix door operates properly when changing from
code No.
toby pushing DEF switch.
Full cold Full hot
6. Set up code No.in Self-diagnosis STEP 4.
7. Attach water cock rod to air mix door lever and secure with clip.
8. Rotate air mix door lever (CLOCKWISE completely) and hold
water cock rod and link lever in the full cold position.
9. Attach water cock rod to link lever and secure with clip (white
mark on cable housing should be centered under the retaining
clip).
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TROUBLE DIAGNOSES
Air Mix Door Motor (Cont'd)
HA-85

Intake Door Motor
TROUBLE DIAGNOSIS PROCEDURE FOR INTAKE DOOR=NBHA0092SYMPTOM:
IIntake door does not change.
IIntake door motor does not operate normally.
Inspection FlowNBHA0092S01Without Navigation SystemNBHA0092S0101
SHA247F
*1: HA-44
*2: HA-129
*3: HA-132
*4: HA-135
*5: HA-141*6: STEP-BY-STEP PROCEDURE
(HA-45), see No. 13.
*7: HA-90
*8: HA-94
*9: HA-66*10: HA-45
*11: HA-66
*12: HA-65
*13: HA-139
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TROUBLE DIAGNOSES
Intake Door Motor
HA-87

SYSTEM DESCRIPTION=NBHA0056Component PartsNBHA0056S01Intake door control system components are:
1) Auto amp.
2) Intake door motor
3) A/C LAN system (PBR built-in mode motor and air mix door motor)
4) In-vehicle sensor
5) Ambient sensor
6) Sunload sensor
7) Intake sensor
System OperationNBHA0056S02The intake door control determines intake door position based on the ambient temperature, the intake air
temperature and the in-vehicle temperature. When the ECON, DEFROST, or OFF switches are pushed, the
auto amplifier sets the intake door at the ªFreshº position.
RHA874H
Intake Door Control SpecificationNBHA0056S03
RHA136G
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TROUBLE DIAGNOSES
Intake Door Motor (Cont'd)
HA-89

2 CHECK FOR AUTO AMP. OUTPUT
Set up Self-diagnosis STEP 4.
Measure voltage across auto amp. harness terminals and body ground.
RHA821H
MTBL0466
OK or NG
OK©INSPECTION END
NG©GO TO 3.
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TROUBLE DIAGNOSES
Intake Door Motor (Cont'd)
HA-91

4 CHECK FOR AUTO AMP. OUTPUT
Set up Self-diagnosis STEP 4.
Measure voltage across auto amp. harness terminals and body ground.
RHA823H
MTBL0468
OK or NG
OK©Replace intake door motor.
NG©Replace auto amp.
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TROUBLE DIAGNOSES
Intake Door Motor (Cont'd)
HA-93

Blower Motor
TROUBLE DIAGNOSIS PROCEDURE FOR BLOWER MOTOR=NBHA0094SYMPTOM:
IBlower motor operation is malfunctioning.
IBlower motor operation is malfunctioning under out of starting fan speed control.
Inspection FlowNBHA0094S01Without Navigation SystemNBHA0094S0101
SHA248FA
*1: HA-44
*2: HA-129
*3: HA-132
*4: HA-135
*5: HA-141*6: STEP-BY-STEP PROCEDURE
(HA-45), see No. 13.
*7: HA-98
*8: HA-98
*9: HA-45*10: HA-66
*11: HA-65
*12: HA-66
*13: HA-139
*14: EL-108
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TROUBLE DIAGNOSES
Blower Motor
HA-95

SYSTEM DESCRIPTION=NBHA0062Component partsNBHA0062S01Fan speed control system components are:
1) Auto amp.
2) Fan control amp.
3) A/C LAN system (PBR built-in mode door motor and air mix door motor)
4) In-vehicle sensor
5) Ambient sensor
6) Sunload sensor
7) Intake sensor
System OperationNBHA0062S02
SHA006FF
Automatic ModeNBHA0062S03In the automatic mode, the blower motor speed is calculated by the automatic amplifier based on inputs from
the PBR, in-vehicle sensor, sunload sensor, intake sensor and ambient sensor. The blower motor applied
voltage ranges from approximately 5 volts (lowest speed) to 12 volts (highest speed).
The control blower speed (in the range of 5 to 12V), the automatic amplifier supplies a gate voltage to the fan
control amplifier. Based on this voltage, the fan control amplifier controls the voltage supplied to the blower
motor.
Starting Fan Speed ControlNBHA0062S04Start Up From ªCOLD SOAKº Condition (Automatic mode)NBHA0062S0401In a cold start up condition where the engine coolant temperature is below 50ÉC (122ÉF), the blower will not
operate for a short period of time (up to 126 seconds). The exact start delay time varies depending on the
ambient and engine coolant temperature.
In the most extreme case (very low ambient) the blower starting delay will be 126 seconds as described above.
After this delay, the blower will operate at low speed until the engine coolant temperature rises above 55ÉC
(131ÉF), at which time the blower speed will increase to the objective speed.
Start Up From Normal or ªHOT SOAKº Condition (Automatic mode)
NBHA0062S0402The blower will begin operation momentarily after the AUTO button is pushed. The blower speed will gradu-
ally rise to the objective speed over a time period of 3 seconds or less (actual time depends on the objective
blower speed).
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TROUBLE DIAGNOSES
Blower Motor (Cont'd)
HA-97

1 CHECK POWER SUPPLY FOR FAN CONTROL AMP.
Disconnect fan control amp. harness connector.
Do approx. 12 volts exist between fan control amp. harness terminal No. 3 and body ground?
RHA480G
YesorNo
Ye s©GO TO 2.
No©GO TO 8.
2 CHECK BODY GROUND CIRCUIT FOR FAN CONTROL AMP.
Does continuity exist between fan control amp. harness terminal No. 1 and body ground?
RHA089G
YesorNo
Ye s©Reconnect fan control amp. harness connector. And GO TO 3.
No©Repair harness or connector.
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TROUBLE DIAGNOSES
Blower Motor (Cont'd)
HA-99