E03 appears and the softener stops mid-cycle, often during backwash or rinse.

Safety first: Unplug the AquaHouse softener before opening the control head. Water may discharge if you remove the valve from plumbing; close bypass valves first.

Step-by-step:

• 1. Listen for motor operation: With power on and E03 displayed, place your ear near the control head. A humming or clicking without rotation suggests a jammed cam or weak motor.
• 2. Inspect wiring: Disconnect power. Remove the control head cover. Check the motor harness from the drive motor to the main PCB for loose plugs, corrosion, or damaged wires. Reseat connectors firmly.
• 3. Check for mechanical binding: Manually rotate the cam/rotor (if your AquaHouse model allows) using the manual advance knob or a screwdriver slot. It should move smoothly through positions. If it binds, debris or resin beads may be lodged in the valve—bypass and depressurize before disassembling.
• 4. Test the motor: With the cover off and power restored, start a manual regeneration and observe the motor. If it does not turn at all and wiring is intact, the motor is likely failed.
• 5. Replace the drive motor: Remove mounting screws, disconnect the motor harness, and install a new AquaHouse drive motor assembly. Reassemble, restore power, and run a full regeneration to confirm proper indexing.

If the new motor also stalls, the internal valve body or cam gear set may be damaged and require replacement.