2009 INFINITI QX56 air condition

WATER VALVE CIRCUITHAC-77
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WATER VALVE CIRCUIT
DescriptionINFOID:0000000003775372
COMPONENT DESCRIPTION
Water Valve
The water valve (1) cuts the flow of engine coolant to the front and
rear heater cores to allow for maximum cooling during A/C opera-
tion. It is controlled by the A/C auto amp.
Water Valve Diagnosis ProcedureINFOID:0000000003775373
DIAGNOSTIC PROCEDURE FOR WATER VALVE
1.CHECK WATER VALVE POWER AND GROUND CIRCUITS
1. Disconnect water valve connector F68.
2. Turn ignition switch ON.
3. Rotate temperature control dial (driver) to 32 °C (90 °F).
4. Check voltage between water valve harness connector F68 ter- minal 1 and terminal 2 while rotating temperature control dial
(driver) to 16 °C (60° F).
Is the inspection result normal?
YES >> GO TO 3.
NO >> GO TO 2.
2.CHECK WATER VALVE CONTROL OUTPUT CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect A/C auto amp. connector M50.
3. Check continuity between water valve harness connector F68 (A) terminal 2 and A/C auto amp. harness connector M50 (B)
terminal 46.
4. Check continuity between water valve harness connector F68 terminal 2 and ground.
Is the inspection result normal?
YES >> Replace A/C auto amp. Refer to VTL-7, "Removal and Installation".
NO >> Repair harness or connector.
3.CHECK WATER VALVE POWER AND GROUND CIRCUITS
WJIA1791E
Connector Te r m i n a l s
Condition Voltage
(Approx.)
(+) (-)
Water valve: F68 2 1Rotate temperature
control dial Battery
voltage
WJIA1794E
2 - 46 : Continuity should exist.
2 - Ground : Continuity should not exist.
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Revision: December 20092009 QX56

HAC-78
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
WATER VALVE CIRCUIT
1. Rotate temperature control dial (driver) to 16
°C (60° F).
2. Check voltage between water valve harness connector F68 ter- minal 1 and terminal 2 while rotating temperature control dial
(driver) to 32 °C (90° F).
Is the inspection result normal?
YES >> Replace the water valve.
NO >> GO TO 4.
4.CHECK WATER VALVE CONTROL OUTPUT CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect A/C auto amp. connector M50.
3. Check continuity between water valve harness connector F68 (A) terminal 1 and A/C auto amp. harness connector M50 (B)
terminal 45.
4. Check continuity between water valve harness connector F68 (A) terminal 1 and ground.
Is the inspection result normal?
YES >> Replace A/C auto amp. Refer to VTL-7, "Removal and Installation".
NO >> Repair harness or connector.
Connector Te r m i n a l s
Condition Voltage
(Approx.)
(+) (-)
Water valve: F68 1 2Rotate temperature
control dial Battery
voltage
WJIA1792E
1 - 45 : Continuity should exist.
1 - Ground : Continuity should not exist.
AWIIA0204ZZ
Revision: December 20092009 QX56

AMBIENT SENSORHAC-79
< COMPONENT DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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AMBIENT SENSOR
Component DescriptionINFOID:0000000003775374
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 increases quickly, the pr ocessing 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 comp artment can radiate to the front grille area, loca-
tion of the ambient sensor.
Ambient Sensor Diagnosis ProcedureINFOID:0000000003775375
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 AMBIENT 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.
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1 - Ground: Approx. 5V
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HAC-80
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
AMBIENT SENSOR
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-80, "
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-23, "
A/C Auto Amp. Self-Diagnosis" and perform self-diagnosis.
NO >> 1. Replace ambient sensor. 2. GO TO HAC-23, "
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-23, "
A/C Auto Amp. Self-Diagnosis" and perform self-diagnosis.
NO >> Repair harness or connector.
Ambient Sensor Component InspectionINFOID:0000000003775376
COMPONENT INSPECTION
Ambient Sensor
2 - 26 : Continuity should exist.
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1 - 25: Continuity should exist.
1 - Ground : Continuity should not exist.
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Revision: December 20092009 QX56

AMBIENT SENSORHAC-81
< COMPONENT DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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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
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Revision: December 20092009 QX56

HAC-82
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
IN-VEHICLE SENSOR
IN-VEHICLE SENSOR
Component DescriptionINFOID:0000000003775377
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:0000000003775378
DIAGNOSTIC PROCEDURE FOR IN-VEHICLE SENSOR
SYMPTOM: In-vehicle sensor circuit 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-V EHICLE SENSOR AND GROUND
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Revision: December 20092009 QX56

IN-VEHICLE SENSORHAC-83
< COMPONENT DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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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-V EHICLE 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-84, "
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-23, "
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-23, "
A/C Auto Amp. Self-Diagnosis" and perform self-diagnosis.
5.CHECK CIRCUIT CONTINUITY BETWEEN IN-V EHICLE 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-23, "
A/C Auto Amp. Self-Diagnosis" and perform self-diagnosis.
NO >> Repair harness or connector.
6.CHECK CIRCUIT CONTINUITY BETW EEN 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.
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4 - 32: Continuity should exist.
4 - Ground Continuity should not exist.
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Revision: December 20092009 QX56

HAC-84
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
IN-VEHICLE SENSOR
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-23, "
A/C Auto Amp. Self-Diagnosis" and perform self-diagnosis.
NO >> Repair harness or connector.
In-Vehicle Sensor Component InspectionINFOID:0000000003775379
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.
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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
AWIIA0816ZZ
Revision: December 20092009 QX56