Airbag light can't make up it's mind

Every time I start my truck the airbag light goes off after it's self test and stays off as long as i don't drive away. As soon as I go about two or three feet it comes back on. It started when I had a cooler in the bed of the truck and had to stop suddenly causing the cooler to forcefully hit the back of the bed. The light came on shortly after that and has been doing this ever since. I don't want to go to a dealer because all the dealers around here are quick to rip you off by shotgunning their troubleshooting. Any suggestions?

 

see if you can get a code and go from there

 

Impacts can cause the occupant classification ecu to need to be recalibrated. Does he passenger seat belt light and airbag indicator still work properly when the airbag light is on?

 

I have seen the plug behind the airbag "off" switch come loose, happened to me and was an intermittent light issue.

Your impact of a cooler should have no bearing on this issue