Idaho_Steve_USN

In case it helps others down the road I can confirm that the DIP SW-10 reset procedure mentioned above clears the error code but maintains all the previous user settings (e.g. Date/Time/Filter Change Interval/etc.) This may be a slightly easier remedial action than the full factory reset involving the J68 jumper. I had the exact same scenario as the OP did with a “Watchdog—-Call for Service” message in my J-335 (installed 7-2021) that cleared after a power cycle but was replaced by the “Overheat GFCI Trip Call for Service" and then a GFCI trip after ~4 minutes. This is what I did; 1. Power OFF 2. Open up Control Panel and place DIP SW-10 in ON position 3. Power ON for 10-15 seconds. 4. Power OFF 5. Return DIP SW-10 to previous OFF position and button everything back up 6. Power ON and verify normal operation. Obviously if the root cause isn’t remedied then the error code(s) will return. In my case we apparently got lucky. We had used the tub last night as normal. This morning when I went to do my water chem analysis I found the red tub lights flashing and the “Watchdog” error. The local service tech is “backed up” and will “hopefully call sometime next week” so in some minor desperation I found this site and all the helpful info. Sincere thanks to the OP and others who provided information. No way here in Idaho in December was I looking forward to being without my soak. Steve