Is it possible for a brake sensor to just "go bad"? I am pouring over my pre-purchase inspection and it includes new pads and brake sensors, but my front sensor is showing bad after I took it in for an inspection at the mini dealership. I think it might have gotten messed up but they're saying it's a wear part so it's not covered under anything but maintenance (which I don't have from Mini but do have elsewhere, but with 100 deductible).

My question is does this part just "go bad"? The pads are brand new as should be the sensor unless the dealership I bought from is lying.

 

The brake sensor is just a wire with a loop. When the pad gets low, the sensor wears against the rotor and severs the wire, triggering the brake light. They are on the front left and rear right.
It can 'go bad' if the wire is compromised anywhere along its length or if the connector gets unplugged.

 

and

a worn sensor can not be 'reset', it must be replaced ... but this is not difficult or very expensive.