Nissan Versa

 Sedan Service Manual

Engine » Engine control system (EC) » P0128 thermostat function
Diagnosis Procedure

1.CHECK ENGINE COOLANT TEMPERATURE SENSOR

Check the engine coolant temperature sensor. Refer to EC, "Component Inspection".

Is the inspection result normal?

YES >> GO TO 2.

NO >> Replace engine coolant temperature sensor. Refer to CO, "Exploded View".

2.CHECK THERMOSTAT

Check the thermostat. Refer to CO, "Removal and Installation".

Is the inspection result normal?

YES >> INSPECTION END

NO >> Replace thermostat. Refer to CO, "Removal and Installation".

Component Inspection

1.CHECK ENGINE COOLANT TEMPERATURE SENSOR

Check the engine coolant temperature sensor. Refer to EC, "Component Inspection".

Is the inspection result normal?

YES >> GO TO 2.

NO >> Replace engine coolant temperature sensor. Refer to CO, "Exploded View".

2.CHECK THERMOSTAT

Check the thermostat. Refer to CO, "Removal and Installation".

Is the inspection result normal?

YES >> INSPECTION END

NO >> Replace thermostat. Refer to CO, "Removal and Installation".

Is the inspection result normal?

YES >> INSPECTION END

NO >> Replace engine coolant temperature sensor. Refer to CO, "Exploded View".

DTC Logic

Diagnosis Procedure