heater control vave on 1997 Ford F-150

where is the heater control vavle located. my heater blower works just no hot air

Asked by for the 1997 Ford F-150
According to the documentation I have, there is no heater control valve, this vehicle uses a blend door to direct the hot air by the heater core where it gets heated and then heads into the passenger compartment. Have someone use a scan tool to do sweep of the blend door to see if it is working properly. It should go from a cold position to a hot position and you should be able to see it on the data stream.