Looking for the low pressure switch, (back towards fire wall, black cap on it passenger side) I think I found it, but when I hook up the AC pro that gauge doesn't register any psi, when I hooked up same AC pro to our Acura TL the gauge registered and I was a little down so I added some
In.

So any tips on what's up? Wife's car blows cold air just wanted to see where it's at and if I need to check for leaks or just add some 134a

Thanks fellas.

 

You've found the right one. My RX required perfect alignment/angle and a little muscle to get the hose fitting to lock in place. Give it another shot.