AC compressor stopped working in the middle of a long road trip.

The clutch will not engage, I have verified the fuse and relay are good in the under hood fuse box. I have also jumped the low pressure cycling switch, compressor will not come on.

any other common things I can check with out taking too much apart?

 

Clutch field coil and the clutch air gap.
Just to start with.


Sean

6.0L Tech Folder

 

Take a 3inch jumper wire and try jumping the low pressure switch. if it doesn't work try the high pressure switch. if it engages then it isn't the clutch and the A/C needs serviced.

 

^^^^ I think he already did this. Make sure you jumped the correct switch near the hvac box. If the system is low on 134a refrigerant it will not cycle the clutch. Jumping the low pressure switch should activate the clutch confirming the system needs a charge after the leak is found and repaired.
If you still have nothing unplug the clutch on the compressor and confirm power and ground while jumping the switch. If you have power and ground plus the air gap isn't excessive, suspect a faulty clutch coil.

 

I am confused how jumping the high pressure switch would resolve anything.

 

im pretty sure he meant low pressure switch.

 

Forgive my ignorance, but what does this mean? Mine is doing the exact same thing. Had a long trip over the weekend, worked great for the first half, not so much on the second half. Checked fuse and relay, clutch is still not engaging. I checked the system before I left, freon was full.

 

Any pictures of the switch near the hvac box? I am going to have to do this tomorrow. 91+ degrees down here, no A/C, no bueno.

 

The switch I refered to is below. If you jump the 2 wires in the plug it will kick in the clutch.

 

I will add to make sure you have Freon pressure right


it might be shutoff so the pump don't burn up cause of pressure


kinda a self protect mode if you will

 

OK, so I finally got around to jump the switch. When I first started it up in the morning, A/C worked fine, for about 5 minutes. I got a chance to check the pressure while the clutch was engaged and it is spot on.

After 5 minutes or so, clutch stopped working, so I jumped the low pressure switch, nothing. No clutch engagement. I suspect that the power and ground to the compressor are good because it worked fine for the 5 minutes at start up, so is the next step is the clutch/coil? Thanks for the help guys.

Any recommendations on where to get the parts if in fact it is the clutch/coil?

 

Bump, any ideas? I guess I got noting to loose by putting in a new coil, but hoping there is nothing else I could do before I dig into the compressor. Also, can this be done while still bolted in? If I have to take it out and disconnect it, might be better to just install a new or rebuilt compressor. TIA,

 

I really think you have excessive gap which after minutes of running allows the clutch to slip.

https://www.ford-trucks.com/forums/1...ac-clutch.html

 

I'd verify something first. When you jump the switch and the compressor kicked in but then stopped again after 5 minutes, did you verify at the clutch plug that you had power and ground? The system has a high pressure cutoff switch too. The electro-magnet coil can fail but you want to verify before throwing parts at it.

But if you do find power and ground at the clutch but it simply isn't working then I'd consider replacement.
When mine went a few years back I took into consideration miles, age, probability of getting the correct clutch kit, and cost of kit compared to compressor. It was also tough to ensure I would get the correct clutch and didn't feel like waiting for a part that ended up wrong.
So one Saturday afternoon I sourced the parts locally and it was done.
New compressor, dryer, orifice tube, and 134a + oil. That was 66,000+ miles ago. But I also have to equipment to draw down vacuum on the system and manifold gauges to refill it properly.

 

I did not have to jump the low pressure switch when I first started it up. Worked as it should, but after 5 minutes of operation, stopped working. Then tried to jump the low pressure switch with no luck