Display shows E04 and time-of-day or regeneration settings will not hold.

Safety first: Unplug the softener before opening the control housing. Avoid touching circuit traces with wet hands.

• 1. Power cycle: Disconnect power for 5 minutes, then plug back in. Reset the time and hardness settings. If E04 reappears quickly, proceed to inspection.
• 2. Inspect for moisture: Remove the control cover. Look for condensation, water drips, or salt dust on the control board and display. If present, dry gently with a clean cloth and allow the board to air dry completely. Identify and correct any brine tank overfill or leaks that may be causing moisture.
• 3. Check power adapter: Verify the SoftPro power supply is the correct voltage and firmly plugged into a non-switched outlet. If you have a multimeter, confirm the output voltage matches the label. Replace the adapter if it is out of spec.
• 4. Inspect keypad ribbon: Ensure the keypad/display ribbon cable is fully seated on the control board. Reseat carefully.
• 5. Replace control board: If E04 persists after drying and power checks, the main control board is likely defective. Order the correct SoftPro control board for your model and swap it, transferring any programming as needed. If unsure, have a technician perform the replacement.