Airbag and Brake light flashes

I drive a 1996 Mercury Villager with about 180,000 miles on it. I have recently started noticing that the airbag light will flash and occasionally the brake light will too. Has anyone experience this before and if so what is causing it. I read somewhere that a weak battery might be the cause.

Thanks

http://autorepair.about.com/library/faqs/bl414d.htm

This might be something to look into.

Is it the regular brake light that is flashing too? Or is it the ABS light that’s flashing?

Tester

The circuits, for the two systems, have nothing in common. Have the brake circuit checked (power from fuse #22, brake fluid reservoir level, brake switch) checked.
All the warnings are: “Don’t mess with the Air Bag system; else, you could have an air bag release in your face”.