Brake Switch

The brake switch is mounted on steering column support bracket, under instrument panel. The PCM uses the brake switch to determine when brakes are applied. When brakes are applied (brake switch on) and if PCM sees a TPS opening and a lower speed sensor rate, it recognizes a deceleration condition and opens up the Idle Air Control (IAC) motor. The brake switch signal will also disengage speed (cruise) control operation, if it was engaged.