DTC P106: Stop Lamp Switch Input Circuit Problem: Description

This diagnostic test functions on the assumption that a sudden decrease in non-drive (rear) wheel speed must be caused by a brake application. Non-drive wheel speed and stop lamp switch status are supplied to the PCM through serial data from the Electronic Brake and Traction Control Module (EBTCM).

If there is a 2.5 MPH or greater decrease of non-drive wheel speed in 0.2 second and a transition of the TCC or extended travel contacts of the torque management brake switch without a transition of the stop lamp brake switch the counter is incremented. When the counter reaches 5, Code P106 is set. The counter will be reset to zero if a transition of the Stop/BTSI/Cruise brake switch is noticed before the counter reaches 5.