A broken water flow meter or faulty timer can prevent the display from showing water usage. Also, you'll notice the water softener water flow indicator not working when water softener is bypassed.
Check the bypass valve position first when you see the water softener water flow indicator not working. Move the bypass valve to the service position to send water through the softener if you find the valve in the bypass position.
If the water softener isn't bypassed, then the water flow meter could be stuck or broken.
Follow these troubleshooting steps to fix the problem:
Check water flow using the diagnostic test cycle as described in the owner's manual.
If the water flow meter fails to detect water flow in the diagnostic test cycle, then the water flow meter's turbine could be jammed or broken. Unplug the water softener and shut off the water supply to the softener. Pull off the bypass valve assembly to access the water flow meter turbine. Inspect the turbine and replace it if it's jammed or broken.
If the water flow meter turbine is okay, check the wire harness for damage between the flow meter's sensor and the timer and replace the wire harness if damaged.
If the flow meter's wire harness is okay, then a faulty flow meter sensor or a failed timer is preventing the display from showing water flow. There's no way to test the flow meter sensor so you won't be able to determine whether the sensor or the timer is at fault. Replace the sensor because it costs less than the timer.
If the timer still doesn't detect water flow after replacing the flow meter sensor, replace the timer.
