2001 INFINITI QX4 IDX

RHA461GA
SHA278FA
6. Check Temperature IncreaseNBHA0019S0206Without Navigation System
IPress the temperature increase button until 32ÉC (85ÉF) is
displayed.
ICheck for hot air at discharge air outlets.
If NG, go to trouble diagnosis procedure for insufficient heating
(HA-121).
If OK, continue with next check.
With Navigation System
ITurn the temperature dial clockwise until 32ÉC (85ÉF) is dis-
played.
ICheck for hot air at discharge air outlets.
If NG, go to trouble diagnosis procedure for insufficient heating
(HA-121).
If OK, continue with next check.
RHA462GA
RHA333HA
7. Check ECON (Economy) ModeNBHA0019S02071. Set the temperature 75ÉF or 25ÉC.
2. Press ECON switch.
3. Display should indicate ECON (no AUTO).
Confirm that the compressor clutch is not engaged (visual
inspection).
(Discharge air and blower speed will depend on ambient, in-
vehicle and set temperatures.)
If NG, go to trouble diagnosis procedure for ECON (Economy)
mode (HA-128).
If OK, continue with next check.
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TROUBLE DIAGNOSES
Operational Check (Cont'd)
HA-69

A/C System
TROUBLE DIAGNOSIS PROCEDURE FOR A/C SYSTEM=NBHA0089SYMPTOM:
IA/C system does not come on.
INSPECTION FLOW
RHA866H
*1: HA-72 *2: HA-66 *3: HA-142
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TROUBLE DIAGNOSES
A/C System
HA-71

RHA817H
DIAGNOSTIC PROCEDURENBHA0107SYMPTOM:
IA/C system does not come on.
RHA818H
Auto Amp. CheckNBHA0107S01Check power supply circuit for auto amp. with ignition switch ON.
Measure voltage across terminal Nos. 26, 27, 33 (24, 25, 33) and
body ground.
Voltmeter terminal
Voltage
(+) (þ)
26 (24)
Body ground Approx. 12V 27 (25)
33 (33)
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TROUBLE DIAGNOSES
A/C System (Cont'd)
HA-73

Mode Door Motor
TROUBLE DIAGNOSIS PROCEDURE FOR MODE DOOR MOTOR (LAN)=NBHA0090SYMPTOM:
IAir outlet does not change.
IMode door motor does not operate normally.
Inspection FlowNBHA0090S01Without Navigation SystemNBHA0090S0101
SHA245F
*1: HA-25
*2: HA-66
*3: HA-44
*4: HA-45
*5: HA-129*6: HA-132
*7: HA-135
*8: HA-141
*9: STEP-BY-STEP PROCEDURE
(HA-45), see No. 13.*10: HA-78
*11: HA-81
*12: HA-66
*13: HA-65
*14: HA-139
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TROUBLE DIAGNOSES
Mode Door Motor
HA-75

SYSTEM DESCRIPTION=NBHA0052Component PartsNBHA0052S01Mode door control system components are:
1) Auto amp.
2) Mode door motor (LCU)
3) In-vehicle sensor
4) Ambient sensor
5) Sunload sensor
6) Intake sensor
System OperationNBHA0052S02The auto amplifier receives data from each of the sensors. The amplifier sends air mix door and mode door
opening angle data to the air mix door motor LCU and mode door motor LCU.
The air mix door motor and mode door motor read their respective signals according to the address signal.
Opening angle indication signals received from the auto amplifier and each of the motor position sensors are
compared by the LCUs in each motor with the existing decision and opening angles. Subsequently, HOT/
COLD or DEFROST/VENT operation is selected. The new selection data is returned to the auto amplifier.
RHA870H
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TROUBLE DIAGNOSES
Mode Door Motor (Cont'd)
HA-77

1 CHECK POWER SUPPLY FOR AUTO AMP. (LCU) SIDE
Do approx. 12 volts exist between auto amp. (LCU) harness terminal No. 21 and body ground?
RHA819H
NOTE:
If the result is NG or No after checking circuit continuity, repair harness or connector.
YesorNo
Ye s©GO TO 2.
No©Replace auto amp. (LCU).
2 CHECK SIGNAL FOR AUTO AMP. (LCU) SIDE
Do approx. 5.5 volts exist between auto amp. (LCU) terminals No. 16 or 14 and body ground?
RHA820H
NOTE:
If the result is NG or No after checking circuit continuity, repair harness or connector.
YesorNo
Ye s©GO TO 3.
No©Replace auto amp. (LCU).
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TROUBLE DIAGNOSES
Mode Door Motor (Cont'd)
HA-79

6 CHECK MOTOR OPERATION
Disconnect and reconnect the motor connector and confirm the motor operation.
OK or NG
OK (Return to operate
normally)©Poor contacting the motor connector
NG (Does not operate
normally)©GO TO 7.
7 CHECK MODE DOOR MOTOR OPERATION
1. Disconnect the mode door motor and air mix door motor connector.
2. Reconnect the mode door motor and confirm the motor operation.
OK or NG
OK (Mode door motor
operates normally)©Replace the air mix door motor.
NG (Mode door motor
does not operate nor-
mally)©GO TO 8.
8 CHECK AIR MIX DOOR MOTOR OPERATION
1. Disconnect the mode door motor connector.
2. Reconnect the air mix door motor and confirm the air mix door motor operation.
OK or NG
OK (Air mix door motor
operates normally)©Replace mode door motor.
NG (Air mix door motor
does not operate nor-
mally)©Replace auto amp.
RHA505G
CONTROL LINKAGE ADJUSTMENTNBHA0091Mode DoorNBHA0091S011. Install mode door motor on heater unit and connect it to main
harness.
2. Set up code No. in Self-diagnosis STEP 4. Refer to HA-45.
3. Move side link by hand and hold mode door in DEF mode.
4. Attach mode door motor rod to side link rod holder.
5. Make sure mode door operates properly when changing from
code No.
toby pushing DEF switch.
VENT B/L B/L FOOT D/F DEF
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TROUBLE DIAGNOSES
Mode Door Motor (Cont'd)
HA-81

With Navigation SystemNBHA0098S0102
RHA871H
*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-78
*8: HA-85
*9: HA-85*10: HA-66
*12: HA-66
*13: HA-65
*14: HA-139
*15: HA-45
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TROUBLE DIAGNOSES
Air Mix Door Motor (Cont'd)
HA-83