01 Tahoe rear a/c only blows warm air
 

Thanks to all thoes who helped me with my first problem.
Fixed the front ac cools very nice 38-46 degrees :)
now i have to fix my rear ac it only blows warm air on ac or heat, blower works on all speeds.
What could cause my ac not to work. It's an 01 Tahoe LT with 2 hvac controls in the roof.

Thanks
Kenny
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If you can get to it, check the low pressure line near the rear evaporator to see if it's cold. If it is then I'd suspect a blend door problem.