Control panel displays E01 and the softener will not start a regeneration cycle.

Safety first: Unplug the AquaSoft water softener or switch off the dedicated breaker before removing any covers. Water may be present inside the cabinet; avoid contact with live wiring.

• Power reset: Disconnect power for 5 minutes, then restore power and check if E01 clears. If it does, run a manual regeneration to confirm normal operation.
• Inspect control wiring: Remove the top cover. Locate the main control PCB behind the display. Check all multi-pin harnesses for full insertion, bent pins, or corrosion. Reseat each connector firmly.
• Check low-voltage transformer plug: Ensure the 24V AC transformer plug is fully seated on the control board and not discolored or melted.
• Look for board damage: Visually inspect the PCB for burn marks, swollen capacitors, or cracked solder joints. If any are present, the board is likely defective.
• Test power supply: With power on (only if you are trained and using an insulated multimeter), verify that the transformer is supplying the rated low voltage to the board. If voltage is missing, replace the transformer; if voltage is present but E01 persists, replace the control board.

If you are not comfortable working around live voltage, contact a qualified technician.