AutoCodes

OBD-II / P0128

Coolant temperature below regulating temperature

The engine takes longer than expected to reach operating temperature according to the control module.

Possible causes

  1. 01Thermostat stuck open
  2. 02Incorrect temperature sensor
  3. 03Low coolant level
  4. 04Cooling fan running at the wrong time

Safe checks

  • Check coolant level only when cold.
  • Notice whether cabin heat takes unusually long.
  • Compare cold-start temperature with ambient temperature.

정비소 진단을 대신하지 않습니다. 먼저 이해하고 판단하도록 돕습니다. Original editorial content; always confirm manufacturer procedures and specifications.