FRS brake system warning light
 

I've noticed for the past couple of days that occasionally when braking the parking brake light comes on, and the owners manual says it's also a brake system warning light.
I checked the brake fluid and it's not quite low, but not really full either so I'm not sure if that would be the cause. I read on another thread that it could be sensors, but I think that car had been in some accidents and mine is pristine :)
Is it worth just replacing the fluid, throwing new brake pads on, upgrading the brake lines while I'm at it, and hoping the problem gets resolved?
I don't think any brake maintenance has been done, so it's probably due anyways (2014 frs).
Any advice is welcome

Yes, low fluid will trigger the light.

Low fluid can trigger a light. As pads wear down the fluid level can drop a bit as pistons press out father.