Why does a Blend Door Actuator make a clicking noise only when the air conditioner is turned on?

Answer 1

On Ford products, especially late 1990's Explorers, the blend door is actuated by a small electric sensor/motor device, and the blend door is made of plastic. The part where the two join can break, causing the actuator to spin causing the "death rattle", (or as my wife calles it, "The Bony Fingers of Death" ) sound, like some impatient demon drumming it's bony fingers under your dash. The cause may also be that the gears in the actuator are stripped. Therefore, the fix is complicated. You either have to replace the actuator, ($) OR replace the entire plenum where the broken blend door is located, ($$$! I was quoted $1500.00 OTD) OR BOTH! If you are handy, and have the guts, you can attempt a fix by yourself. The actuator is easy to remove and replace, and a used one can be found at your local wrecking yard. There is also a fix on the internet that will same you a lot of money .. do a webserch for "Ford Explorer Blend Door Fix" and you wil find several entries, some with full color pictures. Good Luck Mark

The clicking noise is usually caused by the gears getting out of alignment and not meshing properly. If it is allowed to continue, it will eventually strip the nylon gears, rendering the motor useless. If caught in time, the motor can usually be rescued.

The most common cause of the mis-alignment of the gears in the motor housing is a broken blend door. When the door breaks, it allows the motor drive axle to "tilt", causing a chain reaction impact back into the motor itself. Replacing the motor will work for a while, but if the root cause isn't addressed, the problem will recur.

Additional information is available on this web site: www.heatertreater Cheap, easy solutions for this problem have been developed and are explained.