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My A/C compressor clutch is not coming on. When I last used the A/C several months ago it was working great. Fuse box under dash on driver side says Fuse 9 is for A/C and Heater. The fuse is good. The engine fan is coming on but the clutch will not engage. I have wiggled the two prong connector while running and the clutch still won't engage. I have the air gap set at 15K and have tapped the clutch plate with a rubber mallet while running and it still won't engage. I was going to put my probe light on the connector but the fan ate it. . I don't have an A/C manifold set to check the system. I question if fuse 9 is the correct fuse as I have seen other fuse numbers come up on search but not sure they are for my year and motor.
Any suggestions to get this going or determine if I need a replacement. I have ZERO electrical skills but have a meter and will try anything if someone will take the time to help. Sandy
Thanks for the help guys. If this is the low side pressure switch, I put a paper clip on both sides of the connectors on the terminal where it plugs in. Clutch did not engage. Then I put the paper clip on the cable on both sides just to make sure I was doing it right and no engagement. I even back probed the switch.
Thanks for the help guys. If this is the low side pressure switch, I put a paper clip on both sides of the connectors on the terminal where it plugs in. Clutch did not engage. Then I put the paper clip on the cable on both sides just to make sure I was doing it right and no engagement. I even back probed the switch.
That's just the connector for the AC compressor. The low side psi switch is near the firewall on the Drier/Receiver.
You really need a set of gauges to verify. It could have developed a small leak, and you wouldn't know.
It should momentarily kick in when 1st selected if all variables are within spec. Even defrost should be momentarily if the system has the correct charge. I just had my wife's Taurus charged with leak detector since we know it has a small leak or it did at 1 time. Shop said to bring it in if it quits again. It was 31°F this morning and the ac compressor kicked it just after I started the car.
I have UV dye in the converted system now and use a black light often in the summer triple digits. Assuming I don't have a leak, if your truck what would you do now? Buy a low pressure switch or something else? Thanks Sandy
That’s good. Bypassing showed that the circuit is working. As stated below there is a reason the system isn’t sending power to the clutch for example low refrigerant charge. The compressor runs in defrost mode to help dry the air.
Originally Posted by timbersteel
You really need a set of gauges to verify. It could have developed a small leak, and you wouldn't know....It was 31°F this morning and the ac compressor kicked it just after I started the car.
If you haven't noticed a leak with the black light, 1st thing would be to change the Low psi switch. I doubt the ac coil is at fault. I did have a 1 faulty Low psi switch that lasted only a year, but the shop swapped it without hesitation as they initially changed it when I had my truck repaired.
If you wait, RA has low psi switches cheaper than anyone, minus shipping. O'Reilly's shows $27 without tax.
Still, I would be inclined to verify with gauges if at all possible. Harbor Freight has a set for under $50 I think. Not the top of the line, but far better than guessing or using the line taps from Walmart.
Thanks again guys. I checked with the black light for first time in a while and saw nothing. From the last time I used it until now, I would think I would see something if it lost all freon.
. I don't have an A/C manifold set to check the system. I question if fuse 9 is the correct fuse as I have seen other fuse numbers come up on search but not sure they are for my year and motor.
