I have an sdt safewatch plus rf ten yr old system, not being monitored. System says low battery on door. I replaced lithium batteries on both doors. Still says low battery. I have one smoke detector and one motion detector. I see no battery in motion detector. There are six batteries in alarm panel.
This may be your system battery. (the back-up in case the AC power goes out) This is located in the main box for the alarm system, you can get a replacement at any Battery's Plus store. Just make sure you take the old one with you so you get the right one.
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