Star Trac TR‑413 is a treadmill lower‑motor controller that uses the 110 V/220 V control board (part #715‑3617 or similar). Common failures include burned‑out MOSFETs or driver ICs, blown input fuses, degraded electrolytic capacitors on the power supply section, and shorted motor‑drive traces caused by mechanical vibration. For troubleshooting begin with a visual inspection of the PCB for scorch marks or loose components, verify that the 110/220 V supply voltage is present at the board’s input terminals, and check all fuses and the main power capacitor for continuity and ESR. If those are good, test the motor‑drive outputs with an oscilloscope to confirm proper PWM waveforms before proceeding to component replacement.[oss-gpt-20b]