Brake pad warning light never comes on

[Majariwr]

I’ve been reading many threads about the brake pad warning light coming on and what it means and what to do about. In my 87 Carrera, the brake warning light appears to be fine, but neither the brake pad warning light or the seat belt light come on when the ignition is turned on. Since the seat belt buzzer doesn’t buzz, I’m assuming the the seat belt issues are likely related to the seat belt the relay. But this is about the brake pad warning light. Other than the bulb being bad, what else would cause the warning light to never come on, even on start up?