Pressure switch 1997 bmw 318ti I jump the low pressur switch conector and compressor come on replaced the sensor and still the compressor wont come on check fuses they are all good, alse check the climate control unit and it is working manually click the relay and a work don't know what alse can i check for

SOURCE: 99 Suburban A/C Not working

The A/C pressue switch may be bad as well. Also the mode switch on the control head inside the vehicle. There are many other exsisting problems pertaining to a/c. I suggest a manual from Auto Zone for many faults can be noted especially wiring can be at fault

SOURCE: I need to know how to jump the ac low pressure to get my ac compressor to come on.

If you look on the low pressure side of the AC system you will see a plug that is incorporated in to the line. It will have two wires leading to it. Remove the plastic clip that attaches the two wires to the sensor and use a short piece of wire to connect the two terminals in side the plug by putting the ends into the cap. This will bypass the low pressure sensor and allow the AC clutch to engage and begin to cycle again. Remember this low pressure switch is there for a reason. If you don't add more r-134 to the system and allow the AC compressor to cycle you will destroy the compressor. You need to charge the system when you bypass the low pressure switch and get the system up to full charge status and reconnect the switch.

SOURCE: 1996 lincoln towncar. No a/c compressor engagement unless jumped

the control unit is no good.i had a similar situation with a 98 tracker,and installed a switch to give it a ground for the compressor relay that comes from the a/c computer module.
it works good and goes on and off with the a/c switch.

SOURCE: clutch won't engage on air conditioning compressor

The air gap may be too wide between the clutch disc and plate. It usually happens from wear. You can test this possibility by engaging the clutch electrically as you have done and then push on the disc slightly with the handle of a hammer or screwdriver. Be careful not to get your hand or fingers too close while the engine is running. Basically you are helping the magnetic field pull the disc in. I hope this helps.

SOURCE: My ac is not working on my 2000 mustang 3.8L. I'm

You were close! Most Fords have a CCRM (Continuous Control Relay Module) thats on the passenger side fenderwell. It has 4 relays: one for the AC compressor cluth, one for the fuel pump, and two for the electric fan (high- and low-speed.) The AC is the one that fails the most. You can replace the CCRM by removing the intake air filter box and working through the fenderwell openings. If it gets to difficult you must remove the wheel and splash cover to replace it from the wheel opening.