Examination
1. Press the air conditioning button and check how the compressor clutch works. If the clutch does not work, remove the air conditioning pressure sensor and short-circuit its contacts with a jumper. If the clutch now works, then the pressure in the system is too low or too high and the system must be inspected in a specialized workshop.
2. If the clutch still does not engage, check if there is voltage at the clutch contacts. If there is voltage, connect the compressor clutch contact directly to the positive battery terminal. If the clutch does not engage, it is faulty and must be replaced.
3. If there is no voltage at the compressor terminals, check the appropriate fuses. If the fuses are OK, remove and check the compressor relay.
4. With the relay removed and the ignition on, connect contacts 3 and 5 of the relay socket with a jumper and check if the clutch works. If it still does not work, then the wiring in the compressor circuit is broken.