1999 Ford F-150 heater not working in cold weather
1999 FORD XLT TRUCK
1999 FORD F-150
In the summer heater works fine. In winter the heater blows cold air only. Replaced thermal switch on dash board. Checked heater core hoses under hood they are both hot when engine is at normal op. Temp.
signed, cold feet
have the same problem?
Wednesday, December 9th, 2009 AT 10:09 AM
Check and test the thermostat and the heater control valve
Wednesday, December 9th, 2009 AT 10:17 AM
Welcome to the forum, I'd have to check the blend door in picture. With the blend door in one position, ac, other position, the air has to go through the heater core.