Air condition blower does not work in the rear ac nothing comes out but front air blows fine.2003 suburban?

If the rear a/c runs on its own switch, check the switch, and if it works, you can check the blower motor, as the rear a/c has its own blower motor separate from the front. Should be located within the housing of the rear a/c. If the vehicle is still covered under warranty, this problem may be covered.