Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature)
Was bedeutet das?
Code P0128 indicates the engine coolant temperature has not reached the thermostat's regulating temperature within a specified time after starting.
Haftungsausschluss: Dieser Diagnosecode ist Teil des OBD2-Standards und gilt für Volkswagen Taos Modelle von 1996 bis 2026. Bitte beachten Sie jedoch, dass dies von der genauen Motorkonfiguration abhängt.
Häufige Ursachen
Defekter oder festsitzender Thermostat
Defekter Kühlmitteltemperatursensor (ECT)
Kühlmittelleck oder niedriger Kühlmittelstand
Zu beachtende Symptome
- Motorkontrollleuchte leuchtet
- Erhöhter Kraftstoffverbrauch
- Motor geht aus wenn er kalt ist
- Kühlmitteltemperaturwarnleuchte leuchtet
Wie man diagnostiziert
Häufige Lösungen
Replace the Engine Coolant Thermostat: This is the most frequent cause of a P0128 code. The thermostat is likely stuck in the open position, allowing coolant to continuously circulate through the radiator, preventing the engine from reaching its optimal operating temperature. Ensure to use an OEM or high-quality aftermarket thermostat with the correct temperature rating for your specific vehicle.
Replace the Engine Coolant Temperature (ECT) Sensor: If the ECT sensor is providing an inaccurate, consistently low temperature reading to the Powertrain Control Module (PCM), the PCM will incorrectly believe the engine is too cold and trigger P0128, even if the engine is at proper operating temperature. This is less common than a faulty thermostat but a definite possibility.
Flush and Refill Cooling System: If the coolant level was low, or the coolant is old, contaminated, or has an incorrect mix ratio, a proper flush and refill with the correct type and concentration of coolant can resolve issues related to poor heat transfer or air pockets within the system. Ensure proper bleeding of air from the system after refilling.