I have a 1999 ford ranger 4 cylinder, I know it's not an f150 but I haven't found any good ranger forums :\

The a/c just quit working one day. I found a burnt relay, so we replaced it. Didn't find any popped fuses or anything else. If I give 12volts straight to the compressor it runs fine. I jumped the hi/low psi switches, wot switch and some other deal that looked like another wot? lol

Still didn't get anything. I checked some wires on the back of the dash (back of switches) and on the temp setting I didn't find any voltage. Is the a/c switch supposed to give power to that which kicks the compressor on?

I also found a few little relays under the dash, are any of those part of the a/c system?

Please help, not sure what else to check.

Thanks!

 

The compressor clutch relay is out under the hood. Did you test for power there when you replaced the relay? Also did you check all the fuses in the dash and under the hood. Try your AC in AC max AC and defrost and see if it works in any of those settings. If it works in one setting and not another it could be the selector switch. I would say if it doesn't work on any setting and both switches are jumped you should start checking the wires for a break because it should have power.

 

A while ago the blower motor stopped working so I found a burnt relay, replaced that. Then found another burnt relay so replaced that. and since then I haven't had the compressor come back on. Maybe the clutch is bad and just popping each new relay??