Ford Repair Questions? Ask a Mechanic for Answers ASAP
I am giving you the information needed.
year is 1998 ford expediction and type is v8 triton 5.4L
Mileage is 216076
so far I only check fues on the lower compartment of the driver side. I am waiting for my answer.
If the complaint is no temperature control of the front heater/AC system and all AC system tests pass, the engine temperature is ok, the heater hoses are hot, and the rear heater/AC system (if equipped) works fine, the problem is likely a broken Temperature Blend Door. To test, remove the function control panel. At the Temperature Control Knob, back probe the Yellow/Light Green wire with a digital voltmeter. This wire is the signal wire of the potentiometer in the Temperature Control Switch, which operates off a 5 volt reference from the Blend Door Actuator (BDA). The changing voltage on this wire informs the BDA of the requested temperature and it drives the Blend Door accordingly. With the key on, slowly rotate the knob back and forth while watching the voltmeter for a smooth transition between approximately 0.5 volts and 4.5 volts. If the voltage is correct and it is possible to hear or feel the BDA moving but the temperature is not changing, the Temperature Blend Door is broken and needs replacing.
I Just want you to know when I turn on the front AC it do not work either, so it is both Heater and AC at the front. Please reply to me thank you.
It definately sounds like either the Blend Door Actuator is defective or the actual Blend Door.