That is probably your problem! So, when you turn on for AC, the dashboard sends 12v power
to the dashboard fan and the clutch and starts the system.
The problem could be a blown fuse, or an open circuit to the clutch.
There is a pressure sensor connected to the low pressure side of the freon line.
(One of the lines (pipes) is called the high side freon line and the other the low side.).
The sensor contains an electrical switch that controls the off/on condition of the compressor.
That switch is there to prevent damage to the compressor if the freon pressure is too low.
There usually is also a high side switch to also prevent damage if the pressure is too high.
The compressor must have lubrication to avoid damage. The lub. is contained in the freon.
The AC repairman should know all this, so the problem might be another electrical problem.
These sensors usually give no trouble, so maybe the AC guy forgot or didn't know.
You can bypass these circuits, by disconnecting the electrical circuit at the compressor
and momentarily connecting 12volts directly to it. Most connections contain both battery and ground.
If the magnetic clutch engages and the compressor turns, you have proved an electrical circuit problem.
If the clutch engages and the compressor does not turn, you have proved a compressor problem.
The compressor could have so much lub. and or freon in the cylinders that the pistons are locked.
Good Luck, be careful!
You may want to find a better mechanic, the first one just cost you the price of a compressor without troubleshooting the magnetic clutch. Put a volt meter on the clutch pull on connector and check for 12 volts, then hit the clutch coil with the ohm meter to verify the magnet coil is good. Now check if the ambient temperature sensor is working in range if you get no 12 volts at the clutch wire, if the ambient sensor tells the A/C control circuit that it's winter cold outside the A/C won't turn on.
You must be thinking that all cars are made exactly the same way and that simply by telling us it doesn't work, we can look into a crystal ball and come up with an answer.
But you're wrong. Every car is different. So start with the basics by providing year, make, model and engine. and THEN ask your question. You'll get much better answers instead of universal wild guesses
Omg your compressor is not kicking on simply because there is no power going to it. Thats as simply as it gets. Now why there is no power going to it well that mistery has to be yet uncovered. There are myriad reasons why your car's computer is not commanding your ac compressor on. But the only way to find out is by having it checked out by a certified ac technician. Otherwise you will continue to throw your money away in unnecessary parts and repairs.
Bad A/C relay, or fuse. Possibly a bad pressure switch, Bad switch in your heat/A/C control panel. Did you check to see if you were getting voltage to the compressor clutch? Did you jump the compressor with a 12 volt wire to see if it will actually kick on at all?
http://www.obd2works.com, as a professional auto diagnostic tools online supplier, providing our customers with a vast range of high-quality and affordable automobile maintenance tools.Our main business line covers: Automotive Professional Diagnostic Tools for OBD I and OBD II compliant vehicles; Auto Diagnostic tool, OBD2 Code Scanners, ECU Chip Tuning Tool, Car Key programmer Mileage Programmer as well as other more featured products.
Stressed out because I have taken my car all around and paid over $360 and I still have no working a/c. I got a a/c check and was told it was my compressor. I bought one. Found another company to put it in and charge it. They said the compressor was still not kicking on. They wanted to charge for a diagnostic and I just was financially and emotionally tapped out so I declined. What are reasons that my compressor would not kick on and freon levels are good?
