Code P033, Extended Travel Brake Switch Input Circuit Problem: Notes
WARNING: This page is about a different car, the 1995 Cadillac Eldorado. However, it is still accessible from the selected car via links, so may be relevant.
This test assumes that a sudden decrease in non-drive (rear) wheel speed is caused by a brake application. Non-drive wheels and stoplight switch status are supplied to PCM through the serial data from the EBTCM.