AC blower motor

[tx_sub]

the highest fan speed does not work. the other positions work but not the highest setting. my question is this, is this a sign of the motor going or the switch itself. the other fan speeds don't seem to blow as hard as they used to. is there an easy way to determine which component it the culprit?
thanks y'all

 

[chebywanna]

if the motor was going it wouldn't want to work in lower settings. i would say you have a wire/switch/plug problem. time to wip out the volt meter, or start wiggling, pounding and jumping with another wire, the backwoods way /forums/images/graemlins/waytogo.gif.

 

[rjfguitar]

Sounds like the switch.

 

[pauly383]

On some trucks, like mine, even when it is on high, it blows more air on max a/c than it does norm a/c. Enough of difference to feel/hear /forums/images/graemlins/k5.gif

 

[odee1]

I would make sure that the blower motor you have is for a a/c truck. I work on one awhile back the evap would frost over in a hour or so. I rechecked my charge and temps ok, turned out someone had put a regular fan motor on this thing, it didn't move enough are to keep the coil clear.