Ac compressor not turning on.

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Jun 7, 2015 | 08:12 PM

Peavey1986

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Ac compressor not turning on.

We'll I just put a new motor in my 86 f150. It has factory ac and worked perfict till I changed the motor. Now the compressor is not kicking on. Everything I see is plugged in and the system is full of refrigerant . What should I check first? Is a fuse in line some place?

Jun 7, 2015 | 08:33 PM

ctubutis

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From: Denver Metro Area, CO

I would probably put a voltmeter on the compressor's signal connection and see if voltage is making its way to the compress or not.

I'm guessing this is the original compressor off the old engine?

Jun 7, 2015 | 08:36 PM

Peavey1986

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Yes it is the original compressor . And if there is no 12 volts going to the compressor then what? What sends power to the compressor?

Jun 7, 2015 | 09:40 PM

ctubutis

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The following is from my 1981 EVTM, AFAIK it applies to your 1986 model, too; see if this stuff helps you:

Jun 8, 2015 | 02:38 PM

Franklin2

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99% of the time the system is low on refrigerant. Go in and turn the A/C on, and the fan on high. Go out to the large accumulator can, usually on it or around it is the low pressure switch. Unplug the switch and jump the wires in the plug with a short piece of wire. If the compressor kicks on, you are most likely low on refrigerant.