I just bought my 99 150 back in Feb. I tried the A/C back in April and it didn't work.

This is what I've found so far.

With the A/C turned on, the compressor will cycle on for 2 seconds then off for 7seconds and continues to do this.

When I bypass the cycling pressure switch the compressor will run. I did not let the compressor run this way b/c I thought it may damage it if there was no freon in the system.

So, my question is. Can I be low on freon or is the switch bad? Is it something I can fix myself without getting raped by a dealer?

 

Probably low on freon(F134). You need to have an AC shop check it with gauges. Low on gas will cause short compressor cycles.

 

Total cycle time 10 seconds?
Low on freon, no doubt..

Here's a tip and take it anyhow you want but repair the problem, don't try the leak sealer in a can. Those things usually cause more harm than good.. I have seen leak sealer cost customers in upwards to $1600 for AC repairs because it can clog up everything from the orifice tube to the evaporator itself. Can also harm the compressor ..

FordMasterTech

 

Thanks for the responses. I hope a recharge is all I need!

 

As FordMasterTech said, the only way you could be low on freon, is for it to leak somewhere. May be as simple as a loose connection, but you do need to locate, or have a shop locate the leak and fix it. Hope it all works out for you. My 99 had a leak, the dealer added dye to the freon, and was able to locate the source using a black light.