Display shows E02 and regeneration stops shortly after starting the cycle.

Safety first: Unplug the softener before opening the control head. Close the inlet valve if you will be removing the valve cover.

• Listen for motor operation: Plug the unit back in and start a manual regeneration. Listen for the small motor on the control valve. If it hums but does not turn, the rotor or cam may be jammed.
• Inspect the drive assembly: Disconnect power again. Remove the control valve cover. Check the valve motor, drive gear, and cam/rotor disc for broken teeth, debris, or misalignment. Clear any debris and ensure the cam can rotate by hand with moderate force.
• Check wiring: Verify the motor harness is fully seated on both the motor and the control board. Look for corrosion or broken wires. Repair or replace the harness if damaged.
• Test motor resistance: With the motor unplugged, measure resistance across the motor terminals (refer to Tier1 specs; many small AC motors read tens to hundreds of ohms). An open circuit or short indicates a failed motor.
• Replace faulty parts: If the motor is seized or electrically open, replace the valve motor. If gears or cam are stripped, replace the drive gear kit / cam assembly. If a known-good motor still triggers E02, the control board motor driver is likely defective and the board should be replaced.