E5 error and the softener stops mid‑regeneration or cannot find the home position

Safety: Unplug the unit and close the inlet valve before removing the valve cover.

• Inspect cam and switch: Remove the valve cover to expose the main cam and position switch (often a micro‑switch or optical sensor). Check that the cam is not cracked and that it engages the switch correctly.
• Check switch operation: With power off, manually rotate the cam and listen/feel for the click of the micro‑switch. Use a multimeter to verify continuity changes when the switch is actuated.
• Verify alignment: Ensure the cam is correctly seated on the shaft and has not slipped. Realign according to the Tapworks service diagram if necessary.
• Inspect wiring: Follow the wires from the cam switch to the control PCB. Look for broken insulation, loose connectors, or corrosion. Repair or replace damaged wiring.
• Reassemble and test: Refit the cover, restore power, and initiate a manual regeneration. The valve should move smoothly through all positions without stopping. If E5 reappears, replace the cam position switch or the entire valve head assembly.