[2001 3.0 U engine]
I'm trying to get my AC working again but the compressor is not cycling on. I bought a can of refrigerant to refill the system and some dye because I presume it is leaking (low pressure side 25 psi). I figured before I put the new 134A in i better make sure that I can get the compressor to run. I was assuming that the compressor was not cycling because the refrigerant levels were low. I wanted to test the compressor before adding refrigerant to be sure that it would cycle and that I would subsequently be able to find the leak.

I hot wired the low pressure switch with a paper clip and turned the AC on full but the compressor still would not engage. With the low pressure switch bypassed (and the AC on) I was not getting any voltage between the two pins on the electrical connection which goes to the compressor.

The fuse and the relay do not seem to be the problem. I also don't think its a clutch issue because I don't hear the solenoid snapping (and again i'm not getting voltage at the compressor).

What am i missing? how can I trouble shoot this system?
Is there a special low-refrigerant-fail-safe-restart on this AC system?
Is there a high pressure switch between the compressor and the condenser which could be faulty (ie. high pressure side thinks it has sufficient pressure)?

Recommendations please!!

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2001 6cyl 3.0 2wd Manual Trans.

If the system is out of refrigerant or close, the compressor will not engage.

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My 2002 2.3 has a low side and high side switch, both had to be jumped to engage the compressor on my truck when doing the same test.

Once I filled it to test for leaks I was able to plug in both switches without the jumpers installed.

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2002 Ford Ranger 2 Dr Standard cab 2.3 5 SPD 7.5 373 gears

I guess the OP dumped a can of 134A into the system and the compressor turned on.

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