DTC P0128 Coolant Thermostat (Engine Coolant Temperature Below Thermostat Regulating Temperature): Trouble Symptom
WARNING: This page is about a different variant/trim than selected.
Thermostat remains open.
CAUTION:
After servicing or replacing faulty parts, perform Clear Memory Mode Ref. to
OPERATION , Clear Memory Mode, and Inspection Mode Ref. to
PROCEDURE , Inspection Mode.
DIAGNOSTIC PROCEDURE
| Step | Check | Yes | No |
|---|---|---|---|
| 1 CHECK ENGINE COOLANT. | Is the engine coolant amount normal? | Go to step 2. | Refill the engine coolant. Ref. to ENGINE COOLANT . |
2 CHECK RADIATOR FAN.
|
Does the radiator fan continuously rotate for 3 minutes or more during idling? | Repair radiator fan circuit. Ref. to RADIATOR MAIN FAN AND FAN MOTOR . and Ref. to RADIATOR SUB FAN AND FAN MOTOR . | Replace the thermostat. Ref. to THERMOSTAT . |