clutch not engaging

[kelly2]

have 12volts switching at the climate control switch in the dash, however no 12volts at the WOT A/C cutoff relay under the hood. also, the WOT A/C cutoff relay is staying on all the time (so even if i had the switched 12volts there it wouldn't matter). checked my TPS and it reads a .97 volts. any other thoughts? where does the 12 volts go from the climate control switch? my diagrams don't show. my truck has been a curse since letting crown ford in fayettevile, nc touch it.

 

[Glacier991]

I'll take a look at my wiring diagrams tonight and see if I might be able to help you.

 

[kelly2]

i downloaded a diagram the other day but haven't checked out my truck yet. right now my best guess is the A/C pressure switch. either it's bad/poor connection or i have no pressure. i paid FORD $275 last fall to check for leaks and replace two o-rings on the back off the compressor.

 

[kelly2]

 

[kelly2]

checked it out tonight. At the A/C clutch cycling pressure switch there is a purple (from the climate control switch) which tests good and a red/yellow that still reads ground. I've tested it and can pulse +12V at the red/yellow and get the system to work (though there's one other problem). however it doesn't get cold so my best guess is that i have next to no pressure on that side of the A/C system. i paid ford $275 last fall to check the system and they replace two o-rings at the back of the compressor that were leaking. now i guess there's another leak.

second problem is the the WOT A/C cutoff relay is staying triggered constantly. it's fed from the PCM relay right next to it. the truck is throwing codes from the "FUEL CAP" light staying on in the cluster (i've already replaced the fuel cap and that's not it). i'm gonna try to get it scanned this week and get the codes posted so i can clear those before going further with the A/C.

 

[Glacier991]

The WOT relay IS an "always on until triggered OFF" kind of relay. I am suspecting you are chasing your tail on an undercharged system maybe.