Pool Sensor Faults:
"PPP" push display button and the "P" reading will be either "00" or "54".
If "00" there is an open circuit, look for a break in the wire or replace sensor.
If "54" or higher there is a short circuit - check wire or replace sensor.
Determine Sensors or Controller at Fault
Sensor - Swap sensors over - fault reading should change over to the opposite.
Controller - If it does not change over to opposite, new controller maybe required.
New grommet is supplied with the sensor.