Troubleshooting Motion Detector Battery Issues

Motion detectors play an essential role in the security of your home or business, providing an easy way to detect the presence of unauthorized intruders when the system is armed. Without all of its motion detectors, your system can develop blind spots that pose a security risk. Properly maintaining your sensors is simple and easy and takes only a few minutes. These units use batteries to power their operation, which occasionally requires replacement.

If your panel’s Trouble light illuminates and you have identified the problem as a dead battery, it is time to remove the old power source and replace it with a new one. Here’s what to do:

1. Remove the Motion Detector from the Wall

Use one hand to grip the detector from the top or the bottom firmly and apply force in an upward direction. The detector should disengage from its bracket and easily slide up and out of its mount. If you have trouble releasing the unit, try pulling outward slightly as you push up, or wiggle the unit to help unlatch it from the hooks attached to the bracket. Take care not to use too much force.

2. Remove the Old Battery and Purchase a Replacement

Turn the unit around and examine the back. Locate the battery door at the bottom. The door should easily slide off just as you might remove the cover from a TV remote control. Inside is the battery. Note the direction of the positive and negative terminals as this will be important for correctly reinstalling a fresh battery later and remove the battery.

Smith Thompson motion detectors use a small battery known as a CR 123A, a type of 3-volt battery. You can purchase new CR 123A batteries at most drugstore chains, along with your local RadioShack or Batteries Plus. Take the old battery with you to confirm you’ve purchased the correct type.

3. Seat the New Battery Into the Motion Detecting Unit

Recall the direction in which the old battery was installed and place the new battery into the unit in the same orientation as before. After installation, replace the battery door until it pops into place and fits snugly. At this stage, you may begin to see the light on the front of the unit begin to flash, often in red. This light is a normal part of your motion detector’s reactivation and does not indicate a fault.

4. Replace the Detector on Its Wall Mount

Turn the unit right side up again and observe the holes on the back that indicate where it latches onto the mounting bracket on your wall. Carefully line up these holes with the pegs, then firmly press down to slide the unit onto the bracket. If you have difficulty, remove the unit, re-align it with the pegs, and try again. Your motion detector may blink for up to 15 minutes following reinstallation before the light extinguishes.

If your unit continues to fail to function following a battery replacement, or if your Trouble light remains illuminated for more than 30 minutes afterwards, please contact the Smith Thompson service desk for further assistance.

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