Posts Tagged: P0135 and cooling fans run all the time

P0135 Cooling fan runs all the time

February 7, 2013

Fix codeP0135 Cooling fan runs all the time If you own a Ford Escort or Mercury tracer and encounter a situation where the radiator fans run all the time, or you have a check engine light and trouble code P0135, you may have a shorted oxygen sensor. The official definition of a P0135 is Oxygen Sensor Heater Circuit Malfunction (Bank 1 Sensor 1). That’s the sensor before the catalytic converter. Oxygen sensors have a heating element in them to speed up their ability to sense oxygen in the exhaust stream. … Read More