WARNING: This page is about a different car, the 2004 Buick Regal, 2004 Buick Century, 2003 Buick Regal, and 2003 Buick Century. However, it is still accessible from the selected car via links, so may be relevant.
Scan Tool Output Controls
Scan Tool Output Control
Additional Menu Selection(s)
Description
Brake to Shift Relay
Special Functions-Output Control-Miscellaneous Tests
Command turns the brake to shift relay ON or OFF for 5 seconds.