dcone97

Turned on my ac and I heard my truck idle down a bit when I turned it on but no air came through the vents, I tried to turn it off and on but no air came through, I am pretty sure that the compressor turns on, how could I know? What else could it be?

casey.mikl

If no air is coming through the vents, that means the fan for the ac isn't kicking on. On the passenger side under the dash there's a black box. Hit that with your hand a couple times and turn it on. See if it comes back on.

nrivera04

Have you tried all fan speed settings? Could be a bad resistor. If the fan runs on 4 and no other speed, the resistor is bad.

Other than that you could have a bad relay or motor. Check voltage at the plug on the blower.

digitaltrucker

year make would help! Check for blown fuses

dcone97

2008 f150 fx2 with the 4.6 supercrew

dcone97

I've checked all four settings and nothing happens, I'm gonna look at it today and play around with it a bit

dcone97

gotcha, if it doesn't come back on, how hard is it to replace a fan blower for the AC, and is it expensive?

techrep

iTrader: (1)

not sure what black box Mike is telling you t.o bang on but, you most likely have a blown fuse or a bad blower motor resistor.. the fuse panel is in the passenger side kick panel and the blower motor resistor is located behind the glove box and is very easy to change. 2 scews and a plug.. they are not expensive and this is a very common problem with our year group. if and when you go to replace the resistor you need to get the corret one.. auto temp control or manual. To verify that your compressor is engaging.. open your hood with the motor running select a/c and look at the compressor clutch to see if it is spinning.. this is the part with the belt running across it.. engaged the center section will be spinning. it may even click to disengage while your watching it.

dcone97

I saw the compressed and it's good, I hit the black box and it popped rite on , I'm going to get resistor now to see if that's the problem

dcone97

So I changed out the resistor and its still doing it until I have to hit the black box under neath, could this be my blower motor? What else is in that black box?