Can a thermostat failure trigger a Check Engine Light in the Prius?

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Can a thermostat failure trigger a Check Engine Light in the Prius?

Yes, a thermostat issue can cause ECU temperature-related error codes e.g., P0128 - Coolant Temperature Below Thermostat Regulating Temperature. Discussing OBD-II scanning for error codes can help Prius owners confirm the problem before replacing the thermostat.

Sandeep asked on 13 Feb 2025 14:53:59 pm

1 Answer

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Car Mechanic Expert - on 13 Feb 2025 15:00:45 pm

Yes, a faulty thermostat can trigger the Check Engine Light in the Prius.

Error Codes: The ECU Engine Control Unit may detect temperature-related issues, such as the thermostat not regulating the coolant temperature properly. The specific error code might be something like P0128, indicating that the coolant temperature is lower than expected.
OBD-II Scanning: Running an OBD-II scan will help you confirm the error code, which can guide you in diagnosing and fixing the problem.