On Board Diagnosis Logic
WARNING: This page is about a different car, the 2005 Infiniti G35. However, it is still accessible from the selected car via links, so may be relevant.
Engine coolant temperature has not risen enough to open the thermostat even though the engine has run long enough.
This is due to a leak in the seal or the thermostat stuck open.
ON BOARD DIAGNOSIS LOGIC
| DTC No. | Trouble diagnosis name | DTC detecting condition | Possible cause |
|---|---|---|---|
| P0128 0128 | Thermostat function | The engine coolant temperature does not reach to specified temperature even though the engine has run long enough. | Thermostat Leakage from sealing portion of thermostat Engine coolant temperature sensor |