I've seen the light flicker when turning the wheel, but
not over bumps and such.
It's usually caused by dirty/intermittent connections in
the slip ring at the steering wheel. I think the light
would also be activated if you had intermittent
connections to the seat belt tensioners - corrosion at
plug in connections, for example.
The classic fix for the slip ring problem is to spray a
bunch of contact cleaner into the back of the steering
wheel. I bought a big aerosol can at Home Depot for
about two bucks. Work the plastic tube up toward the
slip ring by going in from behind the wheel (power it
outward to make room). Spray genererously - use a shop
towel to catch and drips. Then spin the wheel from
lock to lock several times. This will clean the contacts.
One treatment - ten minutes work - cured my flickering
When the SRS light is on, your airbag and seatbelt tensioners
are deactivated. I'm not a huge fan of airbags, but I do
like to have the seatbelt tensioners operating.