Gen 2 A/C code 21 33

Compressor not running when I tried to add refrigerant, checked the A/C diagnostic and it gives me a code of 21 and 33 alternately.

I've done some searching of the boards and never saw any talk about code 33.
I'd like to jump the Hi/Low pressure switch to run the compressor to get some gas in there but I don't want to blow anything, the pressure switch has 4 leads, 1- Red, 1-Green & 2- White w/black stripe. Any idea which two get jumped?
'06 with 90k miles,. Thanks in advance.