Infiniti QX56 (JA60). Manual - part 604

WATER VALVE CIRCUIT

HAC-73

< COMPONENT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

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WATER VALVE CIRCUIT

Description

INFOID:0000000005147716

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 Procedure

INFOID:0000000005147717

Regarding Wiring Diagram information, refer to 

HAC-91, "Wiring Diagram"

.

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 18

°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.

WJIA1791E

Connector

Terminals

Condition 

Voltage 

(Approx.)

(+) (-)

Water valve: F68

2 

1

Rotate temperature 

control dial

Battery 
voltage

WJIA1794E

2 - 46

: Continuity should exist.

2 - Ground

: Continuity should not exist.

AWIIA0203ZZ

HAC-74

< COMPONENT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

WATER VALVE CIRCUIT

3.

CHECK WATER VALVE POWER AND GROUND CIRCUITS

1. Rotate temperature control dial (driver) to 18

°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

Terminals

Condition 

Voltage 

(Approx.)

(+) (-)

Water valve: F68

1 

2

Rotate temperature 

control dial

Battery 
voltage

WJIA1792E

1 - 45

: Continuity should exist.

1 - Ground

: Continuity should not exist.

AWIIA0204ZZ

AMBIENT SENSOR

HAC-75

< COMPONENT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

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AMBIENT SENSOR

Component Description

INFOID:0000000005147718

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 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 compartment can radiate to the front grille area, loca-

tion of the ambient sensor.

Ambient Sensor Diagnosis Procedure

INFOID:0000000005147719

Regarding Wiring Diagram information, refer to 

HAC-91, "Wiring Diagram"

.

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

AWIIA0238ZZ

AWIIA0160GB

HAC-76

< COMPONENT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

AMBIENT SENSOR

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 AMBIENT SENSOR AND A/C AUTO AMP. 

1. Turn ignition switch OFF.

2. Disconnect A/C auto amp. connector.

3. Check continuity between ambient 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-76, "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 AMBIENT SENSOR AND A/C AUTO AMP.

1. Turn ignition switch OFF.

2. Disconnect A/C auto amp. connector.

3. Check continuity between ambient sensor harness connector

E1 (B) terminal 1 and A/C auto amp. harness connector M49 (A)

terminal 25.

4. Check continuity between ambient 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 Inspection

INFOID:0000000005147720

COMPONENT INSPECTION

Ambient Sensor

1 - Ground

: Approx. 5V

AWIIA0161ZZ

2 - 26

: Continuity should exist.

AWIIA1039ZZ

1 - 25

: Continuity should exist.

1 - Ground

: Continuity should not exist.

AWIIA1040ZZ