I purchased a 2001 F150 and the ac compressor doesn't work. There is current coming from the wires on top of the canister where it gets recharged and the system checked out to be full of r134. I know that it is not seized up because I can turn it freely with my hand. Can I replace just the clutch or should I replace the whole compressor. Is there something else I should be checking first like some kind of a switch that could have gone bad. I also checked the fuse to the clutch and it is good. Your help is greatly appreciated!!

 

Welcome to the site.

The low-pressure switch has been known to fail - not all that common, but not all that unheard of. With the system known as full - can either pull the connector and ohm across the switch, or put a jumper in the connector to see if the compressor pulls in.

If the switch checks out as good, then suggest to pull the connector on the compressor and check for voltage coming in. If it's there - got a compressor problem. If not - the problem is still upstream in the electrical circuitry.

Not sure about your vintage - however, the clutch is typically replaceable as a unit. If your system is otherwise tight and the compressor hasn't been making unusual noises - suggest this would be the way to go. Opening up systems gets tricky, and also expensive if you have the work done.

Good luck, and keep us posted.

 

Where is the low pressure switch located? If I run a jumper wire where do I connect it to and from what? Sorry not real familiar with the compressor.

 

The low pressure switch should be over by the evaporator and drier on the passenger side of the firewall - the 'top of the canister where it gets recharged'. Not real familiar with your vintage, but thinking it should be a two-wire connector - just run a jumper between the terminals of the connector - effectively making the circuit think that the switch is closed.

 

Hey! Thanks for the reply. The low pressure switch checks out to be working. All of the fuses and relays check out fine too. My next step is to put a current directly to the clutch. Would it work if I supplied current from the power side only of the battery directly to the clutch or do I need to send both power and ground to it?