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EC-422
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POSITIVE CRANKCASE VENTILATION
1. Check hoses and hose connections for leaks.
2. Disconnect all hoses and clean with compressed air. If any hose
cannot be freed of obstructions, replace.
S-ET277
Revision: March 2010 2008 QX56
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![INFINITI QX56 2008 Factory Service Manual REFRIGERANT PRESSURE SENSOREC-423
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REFRIGERANT PRESSURE SENSOR
Component DescriptionINFOID:0000000001365897
The refrigerant pressure sen INFINITI QX56 2008 Factory Service Manual REFRIGERANT PRESSURE SENSOREC-423
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REFRIGERANT PRESSURE SENSOR
Component DescriptionINFOID:0000000001365897
The refrigerant pressure sen](/manual-img/42/57030/w960_57030-1721.png)
REFRIGERANT PRESSURE SENSOREC-423
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REFRIGERANT PRESSURE SENSOR
Component DescriptionINFOID:0000000001365897
The refrigerant pressure sensor is installed at the condenser of the
air conditioner system. The sensor uses an electrostatic volume
pressure transducer to convert refrigerant pressure to voltage. The
voltage signal is sent to ECM, and ECM controls cooling fan system.
Diagnosis ProcedureINFOID:0000000001365899
1.CHECK REFRIGERANT PRESSURE
SENSOR OVERALL FUNCTION
1. Start engine and warm it up to normal operating temperature.
2. Turn A/C switch and blower fan switch ON.
3. Check voltage between ECM terminal 70 and ground with CON- SULT-IIl or tester.
OK or NG
OK >> INSPECTION END
NG >> GO TO 2.
2.CHECK GROUND CONNECTIONS
1. Turn A/C switch and blower fan switch OFF.
2. Turn ignition switch OFF.
3. Loosen and retighten three ground screws on the body.
BBIA0445E
PBIB2657E
Voltage: 1.0 - 4.0V
PBIB1188E
Revision: March 2010 2008 QX56
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![INFINITI QX56 2008 Factory Service Manual EC-424
< COMPONENT DIAGNOSIS >[VK56DE]
REFRIGERANT PRESSURE SENSOR
Refer to EC-86, "Ground Inspection".
OK or NG
OK >> GO TO 3.
NG >> Repair or replace ground connections.
3.CHECK REFRIGERANT PRESSURE INFINITI QX56 2008 Factory Service Manual EC-424
< COMPONENT DIAGNOSIS >[VK56DE]
REFRIGERANT PRESSURE SENSOR
Refer to EC-86, "Ground Inspection".
OK or NG
OK >> GO TO 3.
NG >> Repair or replace ground connections.
3.CHECK REFRIGERANT PRESSURE](/manual-img/42/57030/w960_57030-1722.png)
EC-424
< COMPONENT DIAGNOSIS >[VK56DE]
REFRIGERANT PRESSURE SENSOR
Refer to EC-86, "Ground Inspection".
OK or NG
OK >> GO TO 3.
NG >> Repair or replace ground connections.
3.CHECK REFRIGERANT PRESSURE SENSOR POWER SUPPLY CIRCUIT
1. Disconnect refrigerant pressure sensor harness connector.
2. Turn ignition switch ON.
3. Check voltage between refrigerant pressure sensor terminal 1 and ground with CONSULT-IIl or tester.
OK or NG
OK >> GO TO 5.
NG >> GO TO 4.
4.DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors E5, F14
• Harness for open or short between ECM and refrigerant pressure sensor
>> Repair harness or connectors.
5.CHECK REFRIGERANT PRESSURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between refrigerant pressure sensor terminal 3 and ECM terminal 67. Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 7.
NG >> GO TO 6.
BBIA0354E
BBIA0445E
Voltage: Approximately 5V
PBIB0188E
Continuity should exist.
Revision: March 2010 2008 QX56
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6.DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors E5, F14
• Harness for open INFINITI QX56 2008 Factory Service Manual REFRIGERANT PRESSURE SENSOREC-425
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6.DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors E5, F14
• Harness for open](/manual-img/42/57030/w960_57030-1723.png)
REFRIGERANT PRESSURE SENSOREC-425
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6.DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors E5, F14
• Harness for open or short between ECM and refrigerant pressure sensor
>> Repair open circuit or short to ground or short to power in harness or connectors.
7.CHECK REFRIGERANT PRESSURE SENSOR IN PUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal 70 and refrigerant pressure sensor terminal 2.
Refer to Wiring Diagram.
2. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 9.
NG >> GO TO 8.
8.DETECT MALFUNCTIONING PART
Check the following.
• Harness connectors E5, F14
• Harness for open or short between ECM and refrigerant pressure sensor
>> Repair open circuit or short to ground or short to power in harness or connectors.
9.CHECK INTERMITTENT INCIDENT
Refer to GI-35, "
How to Check Terminal" and GI-38, "Intermittent Incident".
OK or NG
OK >> Replace refrigerant pressure sensor.
NG >> Repair or replace. Continuity should exist.
Revision: March 2010
2008 QX56
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