Brake light remains on. on 1990 Nissan Pickup (D21)

When I start my truck and release the brake, the light on the dashboard remains lit. My brake reservoir is full and the fuse is not blown. is there another reason the light could be on?

Asked by for the 1990 Nissan Pickup (D21)
1 answer
low fluid level, e brake switch and hydraulic failures are the reason for the light coming on.