Blower motor fan doesn't work

[Seahawk]

2003 Explorer with 237k and automatic climate controls. Hot day with a/c running and it begins to fluctuate high and low and then completely off. Contols light is still functional so I replace the resistor and still nothing. Any suggestions on what is the culprit?

 

[Number4]

Is there power at the blower motor?

The AC modules do fail.

 

[Everdream]

if you have auto control you have a blower motor speed controller, this lil son of a #$#$# sits under the dash behind the glove box and can blow up causing everything but the blower motor to work. It looks like this: https://www.dropbox.com/sc/1dz7q16tuyqyfge/AAADVzjS97Gd69s2lXnsXpIIa
BTW, Im still hoping to buy a working one of these cheap if anyone has one, I live in tacoma, wa I just cant afford 80 bucks for the darn thing.