is there a relay under the dash for the blower motor door in a 99 ford explorer

There are seven relays under the dash~

there's a relay box under there, have to search some more~

There are things known as vacuum motors which are really just vacuum operated valves which direct the air to whichever vents you select. If you hear the blower motor and you can direct air to certain positions, it is likely one of these vacuum motors has failed or one of the vacuum lines going to them has a leak.

hans is correct this is a vacuum issue not a relay issue.

do you hear sucking sound like from a vacuum leak under the dash when engaged?

really frustrates me when Ford, GM and Chrysler chose to use old fashioned Butyl Rubber which degrades in less than ten years, becomes rigid, loses all supple qualities, then splits...silicone will never do this, MZB, MINI, BMW all know this and use only silicone vacuum hoses, like dopes we put out an entirely disposable product which screws things up in the future, like automaker "save money now, make it harder to get along with" or do it right and just use silicone replacements....same with heater hoses, do you think the cops would use anything than the very best on their police interceptors...no, only the best~

http://www.summitracing.com/search? keyword=silicone%20vacuum%20hoses&dds=1

you have a small box which is the controller for the door actuater thats not fully whrapping around the actuator door which controls that movement its whrong sized it nessasary to replace that get correct one ( it allows door opening at whrong location both heating and cooling ) 55.00 item poss difficult to put in NOTE OPEN GLOVE BOX RELEAS TAPS ALLOW THE BOX TO LET YOU GAIN ACCESS TO THAT PART JUST RIGHT BESIDE THE HEATER CORE CANT MISS SEEING IT

its a controller that opens and closses blender actuator door that worn or whrong size