90' V8 Brake light moody

[corvairss@sprynet.com]

New to list and wanted to ask about the brake idiot light (not system 
check window) that is displayed on startup tends to stay on 10 seconds 
+/- after all other idiot lights go out and also comes on while brakes 
are applied sitting at stop light.  Checked fluid and all is normal.  
Is this because of thin pads or out of adjustment?
Car stops great and doesn't pull under hard braking.
Thanks for the help in advance.
Steve Short
90 V8
(too many Corvairs to list)