After having a problem with the blower running constantly on high. Even though it was stuck in high blower mode(Even if EATC turned off), the AC and heat appeared to be operating. AC and heat were working correctly. I replaced the blower motor resistor, which fixed the problem. I then decided to run a self diagnostics on the EATC and got this major clicking noise from the blend actuator (behind glove box). I was puzzled with this as the noise continued even while EATC was turned off.

To solve the problem, I unplugged the blender actuator momentarily while the vehicle was running, and it appeared to reset and the noise stopped and everything is working ok thus far.

If anyone has had any similar experiences I would like to hear about it. Apparently this is a common problem in 99 Ford Explorers (Eddie Bauer Edition).

Well problem solved, so I' m a happy operator.