So, for Driver's rear window, motor works, up-down mechanism works, switch at that door works, no response from master power window switch. Sounds like the master switch at your left hand -for that window- is has either dirty contacts, loose connection to wiring harness, or has just plain gone bad. Try popping master switch up and out, check that wire connector is tight in socket, you might try popping connector off, then back on 2-3 times. Can't tell you how to take it apart and check + repair the switch itself. A new master switch can be pricey, but plenty of aftermarket and used around - figure $40 and up.