So, if you have an older PPS transmitter, when you eventually have to replace the battery, that is when you should be on the lookout for this problem. Put the new battery in and the cap on and pressurize it (i.e. put it on a reg and put that on a tank and turn the tank on). Keep your hand on the transmitter. If it starts to get warm (mine took about a minute to notice it getting warm), turn off the tank, depressurize the line, and take the battery back out.
If you could feel the transmitter getting warm, the battery itself will likely be HOT. Toss it, put in a new battery, and try again.
Through it all, also have your computer on and make sure that you are also getting a pressure reading (or not). I got no pressure reading on my computer when the transmitter was having this issue. So, if you get a pressure reading, you're probably good to go. But, I would still monitor it for a minute or two to make sure the transmitter doesn't start to feel warm.