P0128 - COOLANT THERMOSTAT MALFUNCTION

Description of DTC code P0128 Generic

The Fault Code P0128 OBDII means that the Powertrain Control Module has found that the engine has not obtained the desired temperature within the expected time after running the engine. To establish this, it´s based on the time the vehicle has been functioning, the speed of the vehicle, also the reading of the IAT sensor and the reading of the ECT sensor.

Symptoms of fault code P0128 Generic

The Check Engine light is on.

Causes of OBD2 P0128 Generic

A DTC P0128 may be produced by the following difficulties:

Thermostat clogging or leaks.
Low engine coolant level.
Insufficient heating time.
Defective coolant temperature sensor.
ECT cable system may have a short.
Low electrical connection may occur in the ECT sensor circuit.

Possible solutions of the DTC code P0128 Generic

To repair DTC code P0128 you may verify the next components:

Verify coolant resistance and level.
The cooling fan should work properly, check this as it may last longer than desired. Replace if necessary.
The temperature of the ECT sensor must be in the proper parameters, change it if necessary.
The ECT sensor temperature must be in the proper parameters, change it if necessary.
Replace the thermostat.