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Litter-Robot 3: Yellow flashing slowly (Cat sensor)
The Litter-Robot 3 is equipped with a cat sensor that detects when a cat enters and exits the globe.
If a cycle is interrupted or the bonnet is removed, the unit will stop, and the yellow light will flash slowly, about 1x per second.
This will also occur if the cat sensor is activated by a cat entering the globe. The unit will resume its cycle 15 seconds after your cat has left the globe.
You will also receive a notification on your phone if you use the Whisker app.
To ensure the accuracy and reliability of the cat sensor, press the Reset button after making any changes that will affect the weight of the unit, including emptying the waste drawer, adding or removing litter from the globe, or cleaning or moving the unit. This will recalibrate the weight sensor and circuit board to reflect the changed weight.
If your Litter-Robot 3 is displaying a yellow light flashing slowly, this indicates a cycle has been interrupted either by the cat sensor or bonnet removal.
Press the Reset button to resume the cycle.
Success: If your unit returned home and displays a solid blue light, you've been successful.
Unsuccessful: If your unit is not displaying a solid blue light after returning to home position, or cannot complete the cycle, please continue with troubleshooting.
Bonnet troubleshooting
In this article we will troubleshoot the "Cat sensor interrupt" message. If you received a "Bonnet removed" notification in the Whisker app, refer to the Litter-Robot 3: Yellow flashing slowly (Bonnet removed) guide. If you are unsure, troubleshoot both errors.
Cat sensor troubleshooting
Check for obstructions
Check for obstructions that might prevent the cat sensor from functioning.
- Make sure Litter-Robot is on a firm, level surface.
- The cat sensor function can be affected if the unit is on carpeting or a litter mat.
- Check that there are no power cords running underneath the base of the robot that might obstruct movement.
- If Litter-Robot is on a slippery surface like tile or a wood floor, it may shift over time and come in contact with a wall or furniture.
- Make sure your unit is at least one inch away from walls and furniture.
Inspect the litter and waste drawer
- Empty the waste drawer. It's best to empty the waste drawer if it's getting close to full.
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- If you use the Whisker app, press Reset Gauge in the Controls section of the app when you empty the waste drawer to reset the waste drawer level in the app.
- Check for excess litter inside the globe. Using more than 10 lbs of litter can trigger the cat sensor, causing false cat detects.
- Make sure the litter is at or below the raised fill line. Some brands of litter are heavier than others. For these litters, we recommend keeping the litter at least a half inch below the fill line to avoid weight-related errors. Do not use lightweight litter, as this could affect the unit's ability to detect the cat.
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Always remember to push the Reset button after making changes to the unit. This will recalibrate the weight sensor and circuit board to reflect the changed weight.
- From the Home position, press the Power button to turn the unit off.
- Press the Power button to turn the unit back on. Litter-Robot will perform an initial Clean cycle, and the cat sensor will take a new measurement of the unit's weight.
Success: The Litter-Robot should return home displaying a blue 'ready light' status.
Unsuccessful: If your unit is not displaying a solid blue light after returning to home position, or cannot complete the cycle, please continue with troubleshooting.
Test the cat sensor
- Test the cat sensor by pressing the top of the entryway (not the bonnet) down and away, toward the back of the unit. You should be able to feel a slight spring/bounce movement - this is a good sign that the robot can freely move and that there are no obstructions to prevent the cat sensor from functioning.
- From the Home position, press the Reset button to zero the weight sensors.
- Press the Cycle button.
Success: Once the Clean cycle is complete, the unit should go back to blue ready status.
Unsuccessful: If your unit is not displaying a solid blue light after returning to home position, or cannot complete the cycle, you need to replace your base.
Cleaning your Litter-Robot
It's important to deep clean your Litter-Robot every 3-6 months.
Over time, small clumps can accumulate within the internal pocket of the globe, which can contribute to weight-related errors.
Cleaning or soaking the globe thoroughly every 3-6 months will help prevent any excess weight from accumulating within the globe.
Customers with more than one cat may want to perform globe cleanings more frequently.
Issue not resolved?
If you've completed both bonnet removed troubleshooting and cat sensor troubleshooting, but your Litter-Robot is still flashing yellow, you will need either a new bonnet or a new base.
If your issue was a result of a bonnet malfunction, you'll need a bonnet replacement.
If your issue was a result of a cat sensor malfunction, you'll need a base replacement.
What do I do?
My unit is covered by WhiskerCare™
If your Litter-Robot is covered by WhiskerCare™ warranty, you have access to replacement parts, at no cost, to get your Litter-Robot up-and-running quickly.
- Simply log in to your account at litter-robot.com.
- Click on ‘My Robots’ to access the parts available for your robot.
- Select the part you need.
- We’ll ship you the part at no cost, along with detailed instructions.
The warranty on my unit has expired
If your unit is no longer under warranty, we can help you with the necessary parts and instructions to properly fix your unit at home.Parts Needed (choose one):
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