How to replace my ac sensor switch

As a diyer with familiarity in vehicle refrigeration since r12 days, using all equipment (gauges, hoses, can taps, pressure/temperature charts, factory service manuals), and zero compensation from auto manufacturers, dealers, repair shops, etc, I would ask you why you want to replace the ac pressure sensor? Are you aware of the only reason for a pressure sensor is to protect the ac compressor from self destruction if allowed to run without refrigerant? Approximately 95% of vehicle ac system failure is due to the leak no one wants to find but will run to the auto parts store for refill kits containing refrigerant and sealer. Very few repairs result in restoring ac cooling back to factory condition. And adding sealer basically condemns the entire system when repair shops can refuse repairs, fearing sealer contaminating their expensive equipment. This means an expensive rebuild, replacing virtually the entire ac system to remove all traces of sealer.

The pressure sensor simply detects loss of refrigerant, sending a disable signal to the engine computer to prevent powering the compressor. Refrigerant moves lubricating oil throughout a system, returning back to the compressor as a mist, continuing long term lubrication. Lose refrigerant and oil will not return to lube the compressor, resulting in self destruction. The pressure sensor prevents compressor damage. When correct repairs are made and a repair holds a vacuum (last step with gauges showing a vacuum after vacuum pump is shut off), the vacuum holding for 30 minutes means seals, fittings, hoses and parts are sealed back to factory condition and ready for installing refrigerant and makeup oil lost during repairs. A properly repaired ac system capable of holding refrigerant without leaking means pressures are above the point of overcoming the pressure sensor that signals the engine computer to power the compressor.

According to BMW service manuals, refrigerant must be removed before replacing the pressure sensor. Ac repairs are not diy friendly. requiring the same tools and equipment dealers, repair shops and diyers have and use to restore ac cooling back to factory condition.