I have a Jacuzzi J-345 hot tub (purchased in 2004). We recently had a blank LED display. I replaced the main fuse and then had a F1 fault with no circulation pump movement. I replaced the circulation pump and now have an F2 fault after the tub reached the target temp, 102 deg. There was air in both main filters. I let the air out and reset the tub. The fault went away and target temp was reached again and the F2 fault came back. This time when checking the filters for air there was none. I checked the flow switch (following the trouble shooting guide for the J-345) and it ohm'd correctly. I then removed the filters and set the tub to F0 (which has no filtration cycle), reset the tub and within 24 hours the F2 error was back. I am not sure what else to check without getting into the heavy hitters like motherboard, (which was replaced about a year ago due to a short on J9 and J10), or heater.
Looking for assistance.
Thanks,
David