Diagnostic Procedure

CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten two 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
1. OK: GO TO 2.
2. NG: Repair or replace ground connections.
CHECK ENGINE COOLANT TEMPERATURE SENSOR
Refer to Component Inspection .

OK or NG
1. OK: GO TO 3.
2. NG: Replace engine coolant temperature sensor.
CHECK THERMOSTAT OPERATION
When the engine is cold [lower than 70°C (158°F)] condition, grasp lower radiator hose and confirm the engine coolant does not flow.

OK or NG
1. OK: GO TO 4.
2. NG: Repair or replace thermostat. Refer to WATER INLET AND THERMOSTAT ASSEMBLY
CHECK INTERMITTENT INCIDENT
Refer to TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT .

Refer to Wiring Diagram - ECTS .
1. INSPECTION END