What shall i do? Start by trying a new battery?
What type?
Yes, what you should do is what the book says to do.
First, consider finding your VUE Console manual, and looking on Page 3, where it says what to do:
"LOW BATTERY TRANSMITTER (ID#): Replace the battery in your outdoor Integrated Sensor
Suite (ISS) ..." From that point:
Step 1: Find the Vue ISS Manual.
Step 2: Look on page 14 to find the type of battery.
Step 3: Purchase a new one, see the earlier part of the manual for installation instructions. See the earlier parts of this topic for other advice about resetting the console, etc.
Step 4: Observe results and report them here.