AC low pressure side
 

So, I need to recharge my AC, its starting to get cool; and I really don't feel like paying $268 at the dealer. Anyway, after doing some research, It seems like the low pressure port is under/near the coolant and power-steering tanks. that cap is marked by a '6nm MAX'. Is this correct? Thanks.

1999 S80 T6

Yes just did mine.

wait..so what did you do . And what you mean by recharge the A/C

@ Quietlymknnoise - How did you get the cap off??., it seems kinda tight in space wise
@ akabond- Well top it off with R134-a.
Well I couldn't do it today, too hot, and the engine needs too cool down.... Which can take awhile.

I used a 19mm socket to loosen cap then attached a PRO AC recharge hose to it. I set air temp gauge, read pressure, then pulled trigger and away she charged up. Stopped at 37 psi with air temp of 85 degrees which a little low for air temp.