Topic: 1984 crossfire no power to high pressure switch or compressor clutch??
in Forum: C4 Cooling and Heating Systems
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I just picked up a crossfire with 87k and manual transmission. Most of the gadgets work fine but a/c. Hvac fan blows on all speeds. When selecting a/c max there's no power to compressor or high pressure switch. Low side switch has power. A/c fuse is good. Cooling fan relay works. Any help would be greatly appreciated thx!
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Start tracing power from the A/C "ON" switch is all you can do.
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Mission Viejo, CA - USA
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That's a perfect description of a Low Refrigerant condition. You need gauges to fill the system properly, but you can confirm my suspicion by removing the plug from the low pressure switch, then putting a jumper wire across the two contacts in the low pressure switch connector. Ignition on, a/c on, but engine does not need to be running. You should hear the compressor clutch activate!
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Hot Rod Roy said:
That's a perfect description of a Low Refrigerant condition. You need gauges to fill the system properly, but you can confirm my suspicion by removing the plug from the low pressure switch, then putting a jumper wire across the two contacts in the low pressure switch connector. Ignition on, a/c on, but engine does not need to be running. You should hear the compressor clutch activate!
I agree....
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You said you have power to the low pressure switch. When you jump the low pressure switch, you should have power to your high pressure safety cut-off switch. Do you?
If you have power to your high pressure safety switch, you should have power to your compressor clutch connector. Do you?
If you have power to your compressor connector and your clutch does not actuate, do you have a good ground connection to the other contact in the compressor clutch connector. Do you?
Since you said you have power to your low pressure switch, you should be able to easily see where you have the problem. It's a really simple circuit. Do you have a broken connection somewhere? The wire from the low pressure switch does take a long path around the bottom of the engine on its way to the high pressure safety switch!
in Forum: C4 Cooling and Heating Systems
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