Wel i know in my case it is in the switches its self as sometimes after a rain and I went somewhee and opned the door and the switches got went for the few seconds or so when the door was open in a heavy rain they would not have the lights on for a couple days on the ones that still work most of the time. Then they would work again. I have the power door lock switch on the drivers side that the lights don't work and on the passenger side the power window switch the lights don't work. As far as doing the locking and unlocking or opening and closing of the windows they work fine its just the dreaded lights being burnt out.