Diagnostic Procedure

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 105 and ground with CONSULT-III or tester.
  Voltage: 1.0 - 4.0V
OK or NG

OK: INSPECTION END

NG: GO TO 2.

Fig 1: Checking Voltage Between ECM Terminal 22 And Ground
Courtesy of NISSAN NORTH AMERICA, INC.
CHECK GROUND CONNECTIONS
Models with FDC system, navigation system or telephone
1. Turn A/C switch and blower fan switch OFF.
2. Stop engine.
3. Turn ignition switch OFF.
4. Loosen and retighten ground screws on the body. Refer to "GROUND INSPECTION ".
  
  Fig 2: Identifying Body Ground Screws (Models With FDC System)
  Courtesy of NISSAN NORTH AMERICA, INC.
Models without FDC system, navigation system and telephone
1. Turn A/C switch and blower fan switch OFF.
2. Stop engine.
3. Turn ignition switch OFF.
4. Loosen and retighten ground screws on the body. Refer to "GROUND INSPECTION ".
  
  Fig 3: Identifying Body Ground Screws (Models Without FDC System)
  Courtesy of NISSAN NORTH AMERICA, INC.
OK or NG

OK: GO TO 3.

NG: Repair or replace ground connections.
CHECK REFRIGERANT PRESSURE SENSOR POWER SUPPLY CIRCUIT
1. Disconnect refrigerant pressure sensor harness connector (1).
2. Turn ignition switch ON.
  
  Fig 4: Identifying Refrigerant Pressure Sensor Harness Connector
  Courtesy of NISSAN NORTH AMERICA, INC.
3. Check voltage between refrigerant pressure sensor terminal 1 and ground with CONSULT-III or tester.
  Voltage: Approximately 5V
OK or NG

OK: GO TO 5.

NG: GO TO 4.

Fig 5: Checking Voltage Between Refrigerant Pressure Sensor Terminal 1 And Ground
Courtesy of NISSAN NORTH AMERICA, INC.
DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors E251, E31
- 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.
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 116. Refer to WIRING DIAGRAM .
  Continuity should exist .
4. Also check harness for short to ground and short to power.
OK or NG

OK: GO TO 7.

NG: GO TO 6.
DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors E251, E31
- 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.
CHECK REFRIGERANT PRESSURE SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal 105 and refrigerant pressure sensor terminal 2. Refer to WIRING DIAGRAM .
  Continuity should exist .
2. Also check harness for short to ground and short to power.
OK or NG

OK: GO TO 9.

NG: GO TO 8.
DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors E251, E31
- 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.
CHECK INTERMITTENT INCIDENT
Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".

OK or NG

OK: Replace refrigerant pressure sensor.

NG: Repair or replace.