Diagnostic Procedure

1. Turn ignition switch OFF.
2. Loosen and retighten four ground screws on the body.

   Refer to GROUND INSPECTION .

   Fig 1: Checking Ground Connections

   Courtesy of NISSAN MOTOR CO., U.S.A.

OK or NG

• OK: GO TO  2.
• NG: Repair or replace ground connections.

1. Disconnect engine coolant temperature (ECT) sensor harness connector.
2. Turn ignition switch ON.
   Fig 2: Checking ECT Sensor Power Supply Circuit

   Courtesy of NISSAN MOTOR CO., U.S.A.
3. Check voltage between ECT sensor terminal 1 and ground with CONSULT-II or tester.

   Voltage: Approximately 5 V 

OK or NG

• OK: GO TO  3.
• NG: Repair open circuit or short to ground or short to power in harness or connectors.
  Fig 3: Checking Voltage Between ECT Sensor Terminal 1 & Ground

  Courtesy of NISSAN MOTOR CO., U.S.A.

1. Turn ignition switch OFF.
2. Disconnect ECM harness connectors.
3. Check harness continuity between ECT sensor terminal 2 and ECM terminal 67. Refer to WIRING DIAGRAM - ECTS .

   Continuity should exist. 

4. Also check harness for short to ground or short to power.

OK or NG

• OK: GO TO  4.
• NG: Repair open circuit or short to ground or short to power in harness or connectors.

Refer to COMPONENT INSPECTION .

OK or NG

• OK: GO TO  5.
• NG: Replace engine coolant temperature sensor.

Refer to TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT .

• INSPECTION END