Thermostat

[LarryD]

Does a failing thermostat, either open or closed, throw a fault code...I have a 2011 Jetta TDI Sportwagen, with 64k miles

 

[P2B]

Does a failing thermostat, either open or closed, throw a fault code...I have a 2011 Jetta TDI Sportwagen, with 64k miles

Fail open might throw a code for engine not reaching operating temperature, fail closed probably not.

 

[Tdijarhead]

Fail open might throw a code for engine not reaching operating temperature, fail closed probably not.

Failing closed should send your heat gauge into the red zone.