The Aerobics Inc. 9501001 PaceMaster Pro Series Treadmill Circuit Board is the main control module that manages motor drive, speed regulation, and safety interlocks for the treadmill. Common failure modes on this class of boards include burnt or tripped MOSFETs in the motor driver stage, degraded power‑regulation capacitors causing voltage spikes, and corrupted firmware leading to erratic speed feedback or loss of emergency stop response. Initial troubleshooting should verify that the 48 V DC supply is stable and within spec, inspect for visible component damage or solder bridges on the drive and safety circuitry, and read any stored error codes from the onboard diagnostic port before proceeding with module replacement.[oss-gpt-20b]