Source wording can vary by vehicle and suffix. It is shown as written, not as a universal diagnosis.
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Reported code forms P012800
Complaint CEL on with Code P012800 "The Coolant Temperature is Below the Specified Temperature" Cause Under investigation. This is not an issue that affects drivability or performance and is not a safety concern. The…
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Reported code forms P012800
Active engine diagnosis warning lamp through fault code P012800
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Reported code forms P012800
Check Engine Lamp Illuminated - DTC: P012800 - Thermostat sticks in open state
MERCEDES-BENZ
Reported code forms P012800
Check Engine Lamp Illuminated - DTC: P012800 - Thermostat sticks in open state
MERCEDES-BENZ
Reported code forms P012800 P012809
Coolant / Vacuum / Temperature fault codes - Check Engine Light with DTCs P003313, P0299FA, P0299FB, P226100, P261F71, P012800, and P012809
MERCEDES-BENZ
Reported code forms P012800
Check Engine Lamp Illuminated - DTC: P012800 - Thermostat sticks in open state
MERCEDES-BENZ
Reported code forms P012800 P012809
Coolant / Vacuum / Temperature faults - Check Engine Light with DTCs P003313, P0299FA, P0299FB, P226100, P261F71, P012800, P012809
MERCEDES-BENZ
Reported code forms P012800
Check Engine Lamp Illuminated - DTC: P012800 - Thermostat jams in open state. "The coolant temperature is below the coolant thermostat specified temperature" is stored in the engine control unit.