I tend to turn off the display for a short period of time then back on. Usually in about five minutes things begin to display again.
That is perfectly normal. You have to understand how they work to understand why. TPMS are MUCH more complicated than most people realize.
In your case above, since your display was turned off, it has to wait for the next TPMS to be reported for each sensor. Five minutes is very FAST if that is all it takes for six wheels or more to report. But that time will vary greatly, because the sensors sending out the signals happen at different random times from each wheel.
And here is something everybody should know about external TPMS (and very few know this):
Say your hubcap comes off and breaks a TPMS sensor and now your valve stem is a half mile back on the freeway, with the TPMS still connected, but is now a half mile behind you. Your TPMS will show perfectly normal PSI for that missing TPMS sensor. And it can show as normal PSI for up to around ten minutes. IOW, no problem shown for a totally blow out tire for around ten minutes.
However, if you get a blowout and the TPMS sensor is still next to the RV, you get an instant (like a second delay at the most) that you have a tire problem.
BTW, you may ask me how I know.
But really, I knew in advance that could happen, as I understand how they work. But it's way TMI to put in one of these forum messages.
But they are kinda tricky to understand as they cover many different possible scenarios, other than the missing sensor that is not seen at all for perhaps five or ten minutes. It is related to why it takes that long for your display to work. Waiting for the next digital signal from each TPMS sensor to be transmitted. So when out of range of the sensor, it has nothing new to display so it displays your last known PSI as if there is no problem at all.
But one other thing you should understand is that it takes a long time to get a TPMS update to the monitor unless something changes. So a sensor a half mile back on the road is no update as it is out of range, so all looks perfectly normal as your RV is probably shaking all over the road (depending on which wheel). The sensor DID send the instant update that you have a blowout, but no way can you see it from a half mile down the road.
-Don- Auburn, CA