My mother in law's 2000 300m has a sudden problem that I can't track down. Suddenly, all 4 power windows have stopped working. Luckily, they are all up. I haven't been able to find a blown fuse anywhere. I found the relay for the windows just above the power seat relay; they're the same, so I swapped them but that didn't change anything.
It's as if the relay isn't getting power, so I'm wondering if it could be a breaker or fuseable link somewhere?
Someone suggested the driver's window control panel....but none of the individual window controls on the doors work either.
Yes, I could take it to the dealer but I'm trying to save my mother in law the $75 diagnostic fee

I love this car....it only has 35K miles on it.

Any thoughts?
Thanks!

 

Check for Power and ground at the master drivers control....Everything branches out from there.

 

Thanks I'll report the results here.