I had that problem too, it was happening on and off. When the car was cold the lights wouldn't work and I would get the Airbag light on the cluster. When the car was warm, no airbag light.
This year -25C (-13F) triggered the problem, but last winter at -50C (-58F) those airbag lights were working fine.
Put more solder on all items on both sides of the LED control board, works good so far.
Found this thread right before it started happening on my car, thanks LGT.com