E36 1991 318i Power windows not working

[thanurabw]

I have an E36 1991 318i and I have been having this problem for a year now. The power windows sometimes work and sometimes they don't work at all. They are really unreliable. Sometime i put it down on a drive through and it won't go up again. And I don't know when it will work again too.

All power windows stops working when this happens.
Switches are located on the sides of the gear panel. I have noticed that the lights of the switches also goes out when its not working. I'm assuming power isn't coming to the switches when this happens.

Should I check the ground wires?
Any ideas?

Thanks