P0128-ENGINE COOLANT TEMP SENSOR ENGINE IS COLD TOO LONG

For a complete wiring diagram Refer to Section 8W


  • When Monitored:

    With the engine running.

  • Set Condition:

    When the engine temperature is below 34.0°C.


Possible Causes
  
ENGINE COLD TOO LONG
  



Diagnostic Test

1.CHECK COOLING SYSTEM PERFORMANCE

NOTE: The best way to diagnose this DTC is to allow the vehicle to remain outside overnight in order to have a completely cold soaked engine.


NOTE: Extremely cold outside ambient temperatures may cause this DTC to set.







Did the engine temperature reach a minimum of 80° C (176° F)?

Yes
  • Test Complete.


No
  • Refer to the Service Information for cooling system performance diagnosis. The most probable cause is a Thermostat problem. Also, refer to any related TSBs.
  • Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).