On Board Diagnosis Logic
NOTE:
If DTC P0128 is displayed with DTC P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307 or P0308, first perform the trouble diagnosis for DTC P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308. Refer to
"DTC CONFIRMATION PROCEDURE ".
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.
DTC DETECTING CONDITION AND POSSIBLE CAUSE REFERENCE CHART
| 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. |
|