Tom- You have know idea how much I appreciate your help here. So, no the select button does not do anything. But let me back-up here with some history.
The main controller with the wireless easy touch was installed by Guiton's Pools in 2018 after the Carr Fire damaged the original controller. Everything worked fine. I rarely used the wireless remote because was rebuilding my house. Moved in August of 2020. Everything still working fine. All my pool equipment is in a covered building protected from the weather.
Guiton's has been servicing my pool since 2005. About 2 years ago, I looked out at the pool and the filter was running in the afternoon. Normally runs in am. This was same day as pool gets serviced. I contacted my service person and asked how come he may have left filter running. He said he changed mode to "Time Out" as always does. So, as you know filter should run for 3 hours and then return to "Auto". So, I've kept an eye on that and that issue still exists because everything works fine and I didn't want a spendy repair bill.
So, last Summer, I went to my wireless remote. I turned it on and there was something about syncing or configuring.... then the screen was normal. My device buttons are Spa, Cleaner, Waterfall, Pool Lights. I pressed Waterfall and nothing happened. So I went down to the main controller and turned it on from there. Worked fine. So, turn it off. I don't have a spa, but I pressed the Spa button on the wireless and the Waterfall turned on. So, long story short, the only buttons that worked since then were Menu/Power, P/Filter and Spa/Waterfall. Up/Down Arrows. Select button stopped working. The main thing I use the wireless remote for is the Waterfall , so I didn't pursue repairing it.
This past couple days, I decided I would try to reset the wireless controller and figure it out. I replaced the batteries and went down to the main controller. Went to Settings and tried to sync the address. But I forgot that the wireless Select button won't function so I was unable get it to sync and the wireless controller has "No Com" on the screen.
Also, I opened up the transmitter? which is wired to the main controller. There was a "power" light on and another light flashing every few seconds.
I'm not opposed to opening up the controller as this things are quite spendy to replace. Would be cool to repair it. Guiton's quoted me over $700. Guiton's also advised against switching to the phone app controller as customers have had many issues with that.
Once again, thanks so much for helping me with these issues. Have a great day. Mike