78 trans-am no fan

I have a 1978 trans-am, it is equiped with the 400 pontiac block with the 350 heads. (idk if that is really important)
Well recently the fan just stopped working. I can tell that the AC and Heater are putting out hot and cold air because it eaks out of the vents. I have already checked the blower motor and it is fine.
What else could cause the problem, is it most likely the switch or is there a blower control relay somewhere like on newer cars?

I need an answer asap, i like driving it and the sun has finally reappeared where i live, and i am getting that itch. It is kinda dangerous to drive as it is, and i would love for the ac to work again. any help is greatly appreciated.

Check for power to the fan. Then chek for a good ground.. I had a 79 that the blower quit on and it was a broken ground wire.

thanks man that was it. It is so nice to have that massive ac workin again.

thanks man that was it. It is so nice to have that massive ac workin again.

NP. glad it was an easy fix.

NP. glad it was an easy fix.

Easy as it could be, i pulled the wire, cleaned up the plugs, and it fired right up, you saved me about 150 bucks for the new blower. THanks again, now i can drive my baby with out having to worry about the windows fogging oor passing out from dehydration.