How do you troubleshoot 1998 Camaro power windows that stop working in cold weather?

tRY SPRAYING THE RUN CHANNELS WITH SILICONE.

I can almost guarantee that water is getting into the motor/gearbox housing and freezing . If the motor works when the temp. is above freezing then this is probably the cause. You will have to dismantle and reseal the motor or better yet replace it with a new one.