DTC P0724: TCC Brake Switch Circuit - High Input: Description
WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 2003 Pontiac Grand Prix, 2003 Pontiac Bonneville, 2003 Chevrolet Monte Carlo, 2003 Chevrolet Impala, and 2003 Buick Regal. However, it is still accessible from the selected car via links, so may be relevant.
The TCC brake switch indicates brake pedal status to the PCM. The TCC brake switch indicates that the brake pedal is either applied or released. The normally-closed switch supplies battery voltage to the PCM. Applying the brake pedal opens the TCC brake switch, interrupting voltage to the PCM. When the PCM receives 0 volts at the TCC brake switch input, the PCM turns OFF the torque converter clutch pulse width modulation (TCC PWM) solenoid valve. If the PCM detects a closed TCC brake switch (indicating pedal released) during a number of decelerations, then DTC P0724 sets.