Cause: Charger circuit fault comes when the magnetic contactor for short-circuiting the charging resistor failed to work. This fault typically occurs during the power-up phase when the DC bus capacitors are being charged.

pbf fault in fuji FRENIC MEGA drive indicates Charger circuit fault. This means the pre-charging circuit (used to safely charge the main DC bus capacitors) has failed to operate correctly during startup.

• Visually inspect for signs of damage near pre-charge components.
• Ensure voltage is present and within correct range.
• Check for loose or damaged input terminals.
• Disconnect motor cables and try powering the drive alone.
• The pre-charge circuit is internal — if damaged, the drive typically needs factory repair.