DTC P0126, P0128: Notes
DTC P0126, P0128 [AJ] DETECTION CONDITION AND POSSIBLE CAUSES
DTC P0126
DTC P0128 |
Coolant thermostat |
| DETECTION CONDITION |
DTC P0126
- If the ECT signal never exceeds 71 °C {160 °F}
after the engine runs for a certain period, the PCM determines that the coolant thermostat is stuck open.
MONITORING CONDITIONS
- IAT: -10 °C {14 °F} or above
- Vehicle speed: 6.0 km/h {3.7 mph} or above
(MTX)
- Vehicle speed: 9.4 km/h {5.8 mph} or above
(ATX)
DTC P0128
- The PCM monitors MAF, IAT, VSS and ECT signals and calculates the radiator heat radiation ratio when the following monitoring conditions are met. If the calculated value exceeds the threshold, the PCM determines that the coolant thermostat is stuck open.
MONITORING CONDITIONS
- ECT at engine start: 36 °C {97 °F} or below
- IAT: -10 °C {14 °F} or above
- Difference between ECT at engine start and minimum IAT: 6 °C {10.8 °F} or below
- Vehicle speed: 30 km/h {18.6 mph} or above
(MTX)
- Vehicle speed: 20 km/h {12.4 mph} or above
(ATX)
Diagnostic support note
- This is an intermittent monitor (Engine cooling system).
- MIL illuminates if the PCM detects the above malfunction condition in two consecutive drive cycles or in one drive cycle while the DTC for the same malfunction has been stored in the PCM.
- PENDING CODE is available if the PCM detects the above malfunction condition during the first drive cycle.
- DIAGNOSTIC MONITORING TEST RESULTS is available.
- FREEZE FRAME DATA is available.
- DTC is stored in PCM memory.
|
| POSSIBLE CAUSE |
- ECT sensor malfunction
- Coolant thermostat malfunction
- PCM malfunction
|