Scion tC intermittent heater blowing issue on Scion tC

Some Scion tC owners report experiencing intermittent heater blowing issues, which may stem from a variety of factors including electrical, mechanical, or coolant-related problems. Common causes for heat only functioning while driving include low coolant levels, air pockets in the system, a faulty heater core, an airlocked cooling system, and a malfunctioning thermostat. Additionally, some owners have noted that when the heater blows cold air, it may indicate issues with the blower motor or cabin filter. Problems with the blower motor can lead to the system turning on and off at random intervals, and in some cases, tapping on the blower motor housing has been suggested as a way to assess if the motor is failing and requires replacement. Proper diagnosis is crucial to resolve these issues and ensure the heating system operates effectively in the Scion tC.