I'm getting a flashing air bag light. I have OBD-1. The Snap-On
OBD-1 reader at a local shop can't read the air bag codes without a
special add-on.

Is there any way to obtain the air bag codes through the flashing of
the Air Bag or Engine Needs Servicing lights?

There's a Nissan notice that a connector needs a fastener or the
flashing air bag can appear.

Anyone know which fastener need the fastener? The car had the
passenger air bag replaced years ago after a recall.

I have suppressed the flashing using the toggle the door switch but
soon after driving the code reappears.

The windows were open during a rain storm. The car dried out. It was
about this time the flashing appeared.