Code P090, TCC Brake Switch Input Circuit Problem: Notes
WARNING: This page is about a different car, the 1995 Cadillac DeVille. However, it is still accessible from the selected car via links, so may be relevant.
This test assumes that brake must be applied to bring vehicle to a stop from 30 MPH or greater. If such condition occurs, counter is incremented. When counter reaches 10, Code P090 is set. Counter is reset to zero if a transition of TCC brake switch is detected by PCM before counter reaches 10.