2008 INFINITI QX56 fl sensor

HAC-72
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
MAGNET CLUTCH
>> GO TO 6.
6.CHECK INTAKE SENSOR
Check and verify intake sensor circuit. Refer to HAC-86, "
Intake Sensor Diagnosis Procedure".
>> GO TO 7.
7.RECHECK FOR ANY SYMPTOMS
Perform a complete operational check for any symptoms. Refer to HAC-4, "
Operational Check (Front)" .
Does another symptom exist?
YES >> Refer to HAC-3, "How to Perform Trouble Diagnosis For Quick And Accurate Repair" .
NO >> Replace A/C auto amp. Refer to VTL-7, "
Removal and Installation".
Magnet Clutch Diagnosis ProcedureINFOID:0000000001679810
DIAGNOSTIC PROCEDURE FOR MAGNET CLUTCH
SYMPTOM: Magnet clutch does not engage when A/C switch is ON.
1.CHECK INTAKE AND AMBI ENT SENSOR CIRCUITS
Check intake and ambient sensors. Refer to HAC-22, "
A/C and AV Switch Assembly Self-Diagnosis".
Is the inspection result normal?
YES >> GO TO 2.
NO >> • Malfunctioning intake sensor. Refer to HAC-86, "
Intake Sensor Diagnosis Procedure".
• Malfunctioning ambient sensor. Refer to HAC-78, "
Ambient Sensor Diagnosis Procedure".
2.PERFORM AUTO ACTIVE TEST
Refer to PCS-14, "
CONSULT - III Function (IPDM E/R)".
Does magnet clutch operate?
YES >> • WITH CONSULT-III GO TO 5.
• WITHOUT CONSULT-III GO TO 6.
AWIIA0198GB
Revision: March 2010 2008 QX56

HAC-74
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
MAGNET CLUTCH
1. Reconnect BCM connector and A/C auto amp. connector.
2. Turn ignition switch ON.
3. Check voltage between A/C auto amp. harness connector M49
terminal 4 and ground.
Is the inspection result normal?
YES >> GO TO 8.
NO-1 >> If the voltage is approx. 5V when A/C switch is ON, replace A/C auto amp. Refer to VTL-7,
"Removal and Installation".
NO-2 >> If the voltage is approx. 0V when A/C switch is OFF, replace BCM. Refer to BCS-55, "
Removal
and Installation".
8.CHECK REFRIGERANT PRESSURE SENSOR
1. Start engine.
2. Check voltage between ECM harness connector F54 terminal 70 and ground.
Is the inspection result normal?
YES >> GO TO 9.
NO >> Refer to EC-423, "
Diagnosis Procedure".
9.CHECK BCM INPUT (FAN ON) SIGNAL
Check FAN ON/OFF signal. Refer to HAC-20, "
CONSULT-III Function (HVAC)".
Is the inspection result normal?
YES >> GO TO 12.
NO >> GO TO 10.
10.CHECK CIRCUIT CONTINUITY BETW EEN BCM AND A/C AUTO AMP.
Te r m i n a l s
Condition Voltage
(+)
(-)
A/C auto
amp. con-
nector Te r m i n a l N o .
M49 4 Ground A/C switch: ON Approx. 0V
A/C switch: OFF Approx. 5V
AWIIA0200ZZ
Te r m i n a l s
ConditionVoltage
(+)
(-)
ECM con-
nector Te r m i n a l N o .
F54 70 Ground A/C switch: ON Approx. 0.36 - 3.88V
LJIA0124E
FRONT BLOWER CONTROL
DIAL ON : FAN ON SIG ON
FRONT BLOWER CONTROL
DIAL OFF : FAN ON SIG OFF
Revision: March 2010
2008 QX56

HAC-78
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
AMBIENT SENSOR
AMBIENT SENSOR
Component DescriptionINFOID:0000000001679813
COMPONENT DESCRIPTION
Ambient Sensor
The ambient sensor (1) is attached on the radiator core support (left
side). It detects ambient temperature and converts it into a value
which is then input into the A/C auto amp.
AMBIENT TEMPERATURE INPUT PROCESS
The A/C auto amp. includes a processing circuit for the
ambient sensor input. However, when the temperature
detected by the ambient sensor increas es quickly, the processing circuit retards the A/C auto amp. function. It
only allows the A/C auto amp. to recognize an ambient temperature increase of 0.33°C (0.6°F) per 100 sec-
onds.
This prevents constant adjustments due to momentary conditions, such as stopping after high speed driving.
Although the actual ambient temperature has not changed, the temperature detected by the ambient sensor
will increase. This is because the heat from the engine co mpartment can radiate to the front grille area, loca-
tion of the ambient sensor.
Ambient Sensor Diagnosis ProcedureINFOID:0000000001679814
DIAGNOSTIC PROCEDURE FOR AMBIENT SENSOR
SYMPTOM: Ambient sensor circuit is open or shorted. (40 or 41 is
indicated on A/C auto amp. as a result of conducting the A/C auto
amp. self-diagnosis)
1.CHECK VOLTAGE BETWEEN AM BIENT SENSOR AND GROUND
1. Disconnect ambient sensor connector.
2. Turn ignition switch ON.
3. Check voltage between ambient sensor harness connector E1 terminal 1 and ground.
Is the inspection result normal?
YES >> GO TO 2.
NO >> GO TO 4.
2.CHECK CIRCUIT CONTINUITY BETWEEN AM BIENT SENSOR AND A/C AUTO AMP.
AWIIA0238ZZ
AWIIA0160GB
1 - Ground: Approx. 5V
AWIIA0161ZZ
Revision: March 2010 2008 QX56

AMBIENT SENSORHAC-79
< COMPONENT DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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M A
B
HAC
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1. Turn ignition switch OFF.
2. Disconnect A/C auto amp. connector.
3. Check continuity between am bient sensor harness connector
E1 (B) terminal 2 and A/C auto amp. harness connector M49 (A)
terminal 26.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair harness or connector.
3.CHECK AMBIENT SENSOR
Check the ambient sensor circuit. Refer to HAC-79, "
Ambient Sensor Component Inspection".
Is the inspection result normal?
YES >> 1. Replace A/C auto amp. Refer to VTL-7, "Removal and Installation".
2. GO TO HAC-22, "
A/C Auto Amp. Self-Diagnosis" and perform self-diagnosis.
NO >> 1. Replace ambient sensor. 2. GO TO HAC-22, "
A/C Auto Amp. Self-Diagnosis" and perform self-diagnosis.
4.CHECK CIRCUIT CONTINUITY BETWEEN AM BIENT SENSOR AND A/C AUTO AMP.
1. Turn ignition switch OFF.
2. Disconnect A/C auto amp. connector.
3. Check continuity between am bient sensor harness connector
E1 (B) terminal 1 and A/C auto amp. harness connector M49 (A)
terminal 25.
4. Check continuity between am bient sensor harness connector
E1 (B) terminal 1 and ground.
Is the inspection result normal?
YES >> 1. Replace A/C auto amp. Refer to VTL-7, "Removal and Installation".
2. GO TO HAC-22, "
A/C Auto Amp. Self-Diagnosis" and perform self-diagnosis.
NO >> Repair harness or connector.
Ambient Sensor Component InspectionINFOID:0000000001679815
COMPONENT INSPECTION
Ambient Sensor
2 - 26 : Continuity should exist.
AWIIA1039ZZ
1 - 25: Continuity should exist.
1 - Ground : Continuity should not exist.
AWIIA1040ZZ
Revision: March 2010 2008 QX56

HAC-80
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
AMBIENT SENSOR
After disconnecting ambient sensor (1) connector E1, measure
resistance between terminals 1 and 2 at sensor component side,
using the table below.
If NG, replace ambient sensor. Refer to
HA-45, "
Removal and Instal-
lation".
Temperature °C ( °F) Resistance kΩ
− 15 (5) 12.73
− 10 (14) 9.92
− 5 (23) 7.80
0 (32) 6.19
5 (41) 4.95
10 (50) 3.99
15 (59) 3.24
20 (68) 2.65
25 (77) 2.19
30 (86) 1.81
35 (95) 1.51
40 (104) 1.27
45 (113) 1.07
AWIIA0276ZZ
Revision: March 2010 2008 QX56

IN-VEHICLE SENSORHAC-81
< COMPONENT DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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HAC
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IN-VEHICLE SENSOR
Component DescriptionINFOID:0000000001679816
COMPONENT DESCRIPTION
In-vehicle Sensor
The in-vehicle sensor (1) is located on the lower instrument panel
LH. It converts variations in temperature of passenger compartment
air (drawn in through the integrated fan) into a resistance value. It is
then input into the A/C auto amp.
In-Vehicle Sensor Diagnosis ProcedureINFOID:0000000001679817
DIAGNOSTIC PROCEDURE FOR IN-VEHICLE SENSOR
SYMPTOM: In-vehicle sensor circui t is open or shorted. Using the
CONSULT-III, DTC B2578 or B2579 is displayed. Without a CON-
SULT-III, code 30, 31, 44 or 46 is indicated on A/C auto amp. as a
result of conducting self-diagnosis.
1.CHECK IN-VEHICLE SENSOR CIRCUIT
Is self-diagnosis DTC B2578 or B2579 (with CONSULT-III) or code 30, 31 44 or 46 (without CONSULT-III)
present?
YES or NO?
YES >> GO TO 6.
NO >> GO TO 2.
2.CHECK VOLTAGE BETWEEN IN-VEHICLE SENSOR AND GROUND
AWIIA0164ZZ
AWIIA0165ZZ
AWIIA0166GB
Revision: March 2010 2008 QX56

HAC-82
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
IN-VEHICLE SENSOR
1. Disconnect in-vehicle sensor connector.
2. Turn ignition switch ON.
3. Check voltage between in-vehicle sensor harness connector
M32 terminal 4 and ground.
Is the inspection result normal?
YES >> GO TO 3.
NO >> GO TO 5.
3.CHECK CIRCUIT CONTINUITY BETWEEN IN -VEHICLE SENSOR AND A/C AUTO AMP.
1. Turn ignition switch OFF.
2. Disconnect A/C auto amp. connector M49.
3. Check continuity between in-vehicle sensor harness connector M32 (B) terminal 1 and A/C auto amp. harness connector M49
(A) terminal 26.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair harness or connector.
4.CHECK IN-VEHICLE SENSOR
Check in-vehicle sensor. Refer to HAC-83, "
In-Vehicle Sensor Component Inspection".
Is the inspection result normal?
YES >> 1. Replace A/C auto amp. Refer to VTL-7, "Removal and Installation".
2. Go to HAC-22, "
A/C Auto Amp. Self-Diagnosis" and perform self-diagnosis.
NO >> 1. Replace in-vehicle sensor. Refer to VTL-9, "
Removal and Installation".
2. Go to HAC-22, "
A/C Auto Amp. Self-Diagnosis" and perform self-diagnosis.
5.CHECK CIRCUIT CONTINUITY BETWEEN IN -VEHICLE SENSOR AND A/C AUTO AMP.
1. Turn ignition switch OFF.
2. Disconnect A/C auto amp. connector.
3. Check continuity between in-vehicle sensor harness connector M32 (B) terminal 4 and A/C auto amp. harness connector M50
(A) terminal 32.
4. Check continuity between in-vehicle sensor harness connector M32 (B) terminal 4 and ground.
Is the inspection result normal?
YES >> 1. Replace A/C auto amp. Refer to VTL-7, "Removal and Installation".
2. Go to HAC-22, "
A/C Auto Amp. Self-Diagnosis" and perform self-diagnosis.
NO >> Repair harness or connector.
6.CHECK CIRCUIT CONTINUITY BETWEEN IN-VEHICLE SENSOR MOTOR AND A/C AUTO AMP. (SELF-
DIAGNOSIS CODES 30, 31, 44, 46 OR DTC B2578, B2579)4 - Ground
: Approx. 5V.
LJIA0089E
1 - 26: Continuity should exist.
AWIIA0167ZZ
4 - 32: Continuity should exist.
4 - Ground Continuity should not exist.
AWIIA0217ZZ
Revision: March 2010 2008 QX56

IN-VEHICLE SENSORHAC-83
< COMPONENT DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
C
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M A
B
HAC
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1. Turn ignition switch OFF.
2. Disconnect A/C auto amp. connector and in-vehicle sensor con- nector.
3. Check continuity between in-vehicle sensor harness connector M32 (B) terminal 3 and A/C auto amp. harness connector M50
(A) terminal 31.
4. Check continuity between in-vehicle sensor harness connector M32 (B) terminal 3 and ground.
Is the inspection result normal?
YES >> 1. Replace A/C auto amp. Refer to VTL-7, "Removal and Installation".
2. Go to HAC-22, "
A/C Auto Amp. Self-Diagnosis" and perform self-diagnosis.
NO >> Repair harness or connector.
In-Vehicle Sensor Component InspectionINFOID:0000000001679818
COMPONENT INSPECTION
In-vehicle Sensor
After disconnecting in-vehicle sensor connector M32, measure resis-
tance between terminals 1 and 4 at sensor component side, using
the table below.
If NG, replace in-vehicle sensor. Refer to VTL-9, "
Removal and
Installation".
3 - 31
: Continuity should exist.
2 - Ground : Continuity should exist.
3 - Ground : Continuity should not exist.
AWIIA0168ZZ
Temperature °C ( °F) Resistance kΩ
− 15 (5) 21.40
− 10 (14) 16.15
− 5 (23) 12.29
0 (32) 9.41
5 (41) 7.27
10 (50) 5.66
15 (59) 4.45
20 (68) 3.51
25 (77) 2.79
30 (86) 2.24
35 (95) 1.80
40 (104) 1.45
45 (113) 1.18
AWIIA0218ZZ
Revision: March 2010 2008 QX56