Stoplamp Switch

The stoplamp switch is a normally closed switch that allows battery voltage to be present at the PCM whenever the brake pedal is released. If the brake pedal is applied, the voltage at the PCM goes low indicating the pedal is being depressed. The PCM uses the brake input to determine TCC lockup and shift timing under different driving conditions. For example, if the transaxle is in 2nd gear and the engine speed is low with the brake pedal depressed, the PCM will unlock the torque converter. The stoplamp switch can also aid in determining if a downshift should occur while going down a hill.