Abstract: The present invention provides a diagnostic system and method for health and fitness equipment, designed to bypass non-functional motor control boards and independently test key components such as drive motors, incline motors, alternators, potentiometers, and resistors. The system comprises a portable diagnostic device with multiple connection ports and a mobile application for guiding users through the diagnostic process, capturing real-time data, and generating detailed repair recommendations. The invention supports multiple health and fitness equipment types, including treadmills, ellipticals, steppers, and bikes, offering enhanced versatility. By automating diagnostics, generating professional-grade reports, and enabling predictive maintenance through trend analysis, the invention streamlines equipment troubleshooting, reduces downtime, and improves reliability.