the blower motor doesnt come on at all. No air will blow out of the vents...
Still, what makes you think it's the blower motor? I bought a junk blower motor and still it didn't work. Turns out it is probably the switch assembly. Anyone know how to take apart the dash and get to that?
How do you know the used blower motor is good? Did you test the power connections going to the motor?
Well, Kim, after I tried out the new blower motor and it didn't work either, I got the bright idea to put a voltmeter on the leads that connect to it. Nothing, nada, zilch. Made me scratch my head and then beat it against the wall for not doing that before I went to the junk yard.
If you still need the information on accessing the blower circuit board, you might find it in the sticky thread in the Pick-up Forum. There is a manual for older pick-ups linked there.