My brother couldn't tell if his car's check engine light was on because of the red/green dashboard
He called me panicking last Tuesday because his car felt weird, but the dash looked normal to him. I had to go over and check, and sure enough, the light was on. He's red-green colorblind and said the warning light just blends into the other dash lights for him. It made me realize how many everyday designs, even in something as important as a car, aren't tested for this. Has anyone found a good way to modify or add a clear indicator for stuff like this?