Noise in seat belt tensioner

2005 Mazda 6, 3.0 V-6, 120,000 miles
Have an annoying springy rattling sound in the drivers seat belt tensioner mechanism. Sounds like a flat coil up retractor spring rattling. Any idea how to fix? Very hard to chase down but that is what I heard while in back seat and car was moving for me to find the noise. Also found the yellow 2 wire connector was unplugged here. Plugged it back in and the air bag light comes on the dash. Any ideas on the sensor or light?

Thanks,
Teegolf

Sorry posted in wrong model and am not smart enough to delete.