why would the parking brake light go off and on randomly on 1992 Honda Prelude

light is on during start up then goes off after several miles

Asked by for the 1992 Honda Prelude
Fluid level low or park brake warning light 'switch' not working properly.
1 more answer
Check fluid level in the brake fluid resivoir. Likely its a bit low and it has a level sensor to turn that light on to indicate a low fluid level. The fluid level goes down as the disc brake pads wear down. Might want to get brake system checked to be on the safe side.