My 94 pick up with the 22re. The air conditioning works when I start the truck when the engine is cold. The low side reads 45psi and the high side reads 220psi. After a few minutes the air conditioning compressor clutch turns off. Where do I start? What do I do?

 

Ok once things get hot the Compressor clutch drops out. Does the Blower Motor shut off as well ??

Start at the compressor clutch when it drops out is the voltage still there or did the pressure switch shut it off.

coil can get hot in the clutch and drop out.

one step at a time what does the high side pressure read when it quits is that the 220 psi pressure ?

It comes down to electrical or pressure .

Good luck

 

the blower motor stays on.

the ac shut off at 175psi on the high side and 30psi on the low side this time.

When the ac shut off. The truck was running for only a few minutes. The temperature gauge in the dashboard barely even moved

I didn’t read the voltage going to the compressor while the clutch was engaged, but after the clutch shut off I unplugged the wire going to it and I was getting a reading jumping from 0.1 volts to 0.3 volts.

Then i jumped a wire from the compressor to the battery. The clutch engages but got a zero psi on the low gauge. After that I turned everything off and the pressure gauges equaled out.

 

I let the truck cool down and the air conditioning was working again. I tested the wire going to the compressor and read 13.65 volts.

it’s turning off due to it not getting power.

IS there a way to test the pressure switch?

I read there might be a temperature sensor that turns off the ac if the engine overheats?

I also read that there is a fuse box and relays behind the glove box.

where is the pressure sensors located?

 

The high Low pressure switch is located on the Evaporator coil the low pressure side opens below 30 psi the high pressure side opens at384 psi now these numbers are from a 92 things might have changed.

I also show another pressure switch on the condenser again yours might be different

The AC amplifier can also be getting hot and quitting

Does the AC switch also lose power when the clutch drops out?

Yes fuses and relay are behind the glove box.

I would try and find a copy of the AC circuit for your year Truck any other year could mess you up with wire colors and locations

If I had the correct year I would be glad to share.

Good Luck!