AC Pressure Switch Testing
 

Hi everyone. I have a 2008 E70 3.0 Si. My A/C clutch will not engage when I turn on my A/C. I have freon in the line. I wanted to start doing the process of elimination to see exactly where the problem is, before purchasing a brand new compressor. My mileage is at 90K. My question is: does anyone know how to test the AC pressure switch?

Assume you have read www.newtis.info


Schematics, etc


Also, do you have a BMW code reader/computer to look into the HVAC module??? $150 well spent

Thanks ard for the quick reply. I did hook up my BMW scan/reader tool and there were no errors on the system.

I then connected a can of freon to the system and the gauge shot right up to 100 psi on the low side, but the clutch on the compressor still wouldn't engage. I did not add any additional freon to the system.

I will take some time and go through the www.newtis.info site and see what I can find.