1998 GMC Suburban a/c problems

[bigcountry]

I'm having problems with my a/c first off it wont kick on unless I bypass the low pressure switch, I have replaced both the compressor and the low pressure switch many times, also the heater control unit inside the truck. any help? second does anyone know how to or where to buy block off kit for the rear A/c Ive seen them before on a tahoe but the guy said it was on the truck when he bought it. thanks

 

[zora]

did you put a set of gauges on this time to make sure you have sufficient pressure to activate the pressure switch? I'm not sure what the kit is, a factory or aftermarket kit, but have you tried www.gmpartsdirect.com to see if it is still available?