Did the e-fan conversion some time back. Long story short I think I shorted out hot lead that engages the A/C Compressor Clutch. The AC Clutch still engages when I manually instill 12v to that lead, but the trucks computer/electrical system is not sending that 12v's to the compressor.

I've checked the fuse #11 for the clutch and it appears fine, I'm going to replace anything that has to do with the A/C in regards to fuses just for peace of mind. Anyways, I don't know where the A/C clutch wires run to to test them closer to the fuse box. It's difficult to follow them along the side of the block.

Does anyone have any idea why the A/C might not be sending the signal to engage 12v? Is there any fuses or relays I can check. I know there is a relay box on the drivers side fender, I check the R202 relay but I really don't know how to test the relay. That relay does not CLICK like every other relay I've heard when I turn on the A/C. Maybe thats it? I'm assuming it's a special relay only the dealer will have, so I'm going to replace that.

Any ideas, I know this is a complicated situation but someone must know.

 

you fried the internal circuit in your computer....

 

I had the exact same problem with my '06 when I did my EFan install. I shorted out the AC relay. I took it to Ford and they replaced the relay in about 5 mins I was back on the road.

Wish I could tell you which one it was or its where abouts. I was just told by them it was the AC relay.

And I'd say 99% you didn't fry any internal circuit on the computer.

 

Thanks Scott, I just replaced R202 (which is the relay for the A/C clutch) under the hood and replaced the A/C Clutch fuse #11. It still does not work. That relay was almost $20.

Question. Does the A/C Clutch only get engaged when it detects R134a or pressure in the system? There is none in my system so I want to say that could be the reason the computer is not sending the signal to turn it on. I ask this because I remember when they were filling my system up with freon, the clutch would kick on and off (when it worked).

 

yes, there are high and low pressure switches in the system

 

That is great news, so it may be off for that reason. I am going to have someone put freon in right now, be back with my results.

 

make sure u learn how to do it, its really simple.

 

Yeah it didn't look very difficult and the labor was 90 plus $32 per lb of freon. So this is what happened, we put the freon in, the truck was great and cooled down to 60 degrees. Was amazing having A/C...but it went away within a half hour. The compressor stopped engaging the clutch. Checked the fuses, it's fine. The relay is ok, it throws a CEL when it goes out. It was $160 and it didn't even fix it. I'm going to take it back because the guy is the kind of person you want to bring business, hopefully we can figure it out together.

There is no apparent signs of leaking, I can only think the hi-pressure and lo-pressure switch are not working right.

 

The A/C compressor might have went bad from no freon in it. IIRC, but I'm no specialist at A/C, yet, that the freon is what helps keep the bearings and seals in good standing, and it acts as a lubricating property.

 

The a/c compressor seals will go bad w/o refrigerant (no oil to lubricate). So when you fill up the system it can leak back out real fast.

 

Bingo...

I knew I was right.

I got told this by a A/C tech a couple years ago... not bad.

 

So if that's the case, it will leak out of the bottom of the compressor? Should be very visible if so, I will check it out. I don't see why it would need to be lubricated if it's not running, (the A/C Clutch is never engaged when no freon is present).

 

Freon is a liquid when compressed. At normal atmospheric pressures, it is a gas. You won't see it leaking.

 

I had to have my compressor replaced last summer because the seals in it were leaking. I bet thats all your problem is. You should not have to add refrigerant unless it has a leak.

 

Exactly.

What happened was because he had the A/C basically disconnected and it was never running, it all leaked out. That is why they tell you to use the A/C or defrost at least twice a month.

I haven't needed my A/C/defrost on in a while... I should set it tomorrow to defrost or something to get that compressor running... I don't think I have ever messed with it for about 2 months. :o