The "BRAKE" light comes on for two reasons - to show the E-brake is on (switch stuck?), or to indicate that there is unequal line pressure between the front and rear brakes. The pressure difference could result from air in the lines, leaking components, low fluid in the master cylinder reservoir (putting air in the lines) or a leaky master cylinder (including internal leaks between the front and rear pistons). You need to check the brake system thoroughly to insure you don't have any of those problems. Once the differential pressure switch (on the side of the aBS unit with the lines from the master cylinder running to it) "sets", it may be hard to get it unstuck. It will sometimes respond to a very hard stop. If you try that, AFTER CHECKING ALL THE BRAKE COMPONENTS, make sure you do it in an open area where you can't hit anything in the event the brakes fail.

If the "BRAKE" light is on, the ABS will probably go to "ABS INOP"... so try fixing the "BRAKE" light first. You could also have the codes for the ABS (EBCM computer) read by a shop with an advanced scan tool like the OTC Tech-1 of Tech-2.

 

ok, thanks a lot, will try all of that

 

Smokin'! Very nice looking Firebird.