The Aerobics Inc 9501001 Rev. F is the main motor‑control PCB for a PaceMaster Pro Plus treadmill, handling stepper drive signals, motor current regulation and safety interlocks. Common failure modes reported include burned or tripped relays on the motor driver section, over‑voltage damage to the MOSFET array, and cracked solder joints around the power input pins; users also note intermittent loss of motion control due to a failing microcontroller IC. First‑check diagnostics: verify the 24 V DC supply rail and ensure it is within spec; inspect all relay contacts for corrosion or mechanical wear; perform a continuity test on the motor driver MOSFETs and check the microcontroller’s I²C/SPI lines for proper voltage levels before proceeding to component replacement.[oss-gpt-20b]