For the lights, does messing with the rheostat change the brightness of the temp dial? If so...then the rest of the bulbs are possibly burned out. Because the temp wheel light is powered off the rheostat like the rest of them. Lots of dead bulbs is common....our 300D has every single switch/climate light out. Only the window switches and instruments still have light. I know its the bulbs because I physically checked/tested them, and they're all dead. 
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