1996 Lamborghini VT 2wd, 1994 Ferrari 348 Spider
The air conditioning compressor on my 96 (134a) Diablo does not kick in unless the defroster button is pressed. Have gone through electrical system as best I can and have not found any obvious candidates as to why. Found Freon to be very low this spring and added (3) 12 oz cans. After 1 can, the pressure on the suction side came up to 25 psi, but the 2 additional cans did not bring it up any further. Because comp does kick in on defrost setting, suspect there is not a problem with pressure switches in dehydrator or thermal sensor on evaporator outlet. I checked the pressure with 2 different gauges and both say the same thing. The manual says the older Freon 12 equipped cars took an 800g charge and I am pretty well up there. Am concerned about adding more. Am getting lots of cool out of vents at this point however. Any idea how much Freon these are likely to take? Any thoughts on why the compressor won't engage in the air conditioning mode?