Efka EB301 is a pedal‑motor speed controller used in industrial sewing machines to regulate motor torque and speed via foot‑pedal input. Common failures on this model include burned or tripped MOSFETs/IGBTs, damaged capacitors on the power supply board, and shorted or open foot‑pedal contacts; overheating can also lead to relay or transformer failure. For first‑check diagnostics, verify that the main 24 V DC input is present and stable, inspect the PCB for burn marks or swollen electrolytics, and test the pedal switch continuity and resistance while the unit is powered off. If power checks out, review any fault codes displayed on the machine’s diagnostic panel and perform a visual inspection of the relay contacts and heat‑sink condition.[oss-gpt-20b]