2016 Fit LX CVT. Whenever there's a small bump or hole in the road a rattling noise comes from the vicinity of the driver's side curtain airbag. If the road is smooth there is no noise, but even the ridges between the sections on some roads are enough to produce a quiet sound like sticks ratting against each other. This is at any speed, though of course small irregularities in the road at high speed make more of a bump and a louder noise.

It's hard to trace the exact source of the noise since of course I have to be driving to get the noise, but then I am limited in what I can do to try to detect the source. I have put my fingers on the window, on the dash, and on the trim that includes the one that has a side airbag curtain label on it. I don't feel any vibration. The best I can tell from listening is it is from the trim that follows the driver side of the windshield and has the airbag label on it. It really sounds like sticks rattling behind there, though I guess it could be wires. I'd think it they were hitting the paneling then I'd sense that with my fingers, so it seems more like they are hitting some part of the paneling, or maybe so far down near the base of the windshield where I can't drive and feel with my fingers at the same time. I also tried thumping on the area from the outside of the car with the engine off but I couldn't produce the sound.

The only thing I can think of is there's some part of the airbag that's come loose, maybe just some bundle of wires (but there's no warning lights of any kind). I have no idea what's behind there, but it could be some wires hitting the frame?

If this was my '81 car I'd take out tools and start taking off the paneling, but with the Fit I have no idea how to do this, plus I am highly disinclined to do anything with an airbag inside it.

Any ideas or suggestions? Apart from the annoyance factor, since it could be something to do with the airbag then there's also a safety concern (despite there being no warning lights).

 

I have a GE8 instead of GK5, but I assume the trim removal is similar and not difficult. Check out the service manual for your generation Fit for specific instructions (e.g., often you have to remove trim pieces in a specific order). At least with the GE8 there is a plastic clip behind the piece of trim you're talking about that is destroyed during removal and will need to be replaced.

If you unhook the battery (and wait a bit for extra safety) the airbags should be safe to work around. Again, the service manual has instructions.

Hopefully someone with direct experience with the GK5 can give you more specific information.