Litter-Robot 4: Blue and purple alternating light bar (LitterHopper™ error)

IMPORTANT

1. Make sure your unit is plugged in.
2. Make sure your unit is connected and online.
3. Make sure your firmware is up-to-date. If the app does not give you the option to update, you have the latest version.

About LitterHopper errors

The LitterHopper is designed to automatically dispense litter at the start of the next cycle if the laser sensor detects that litter needs to be added. LitterHopper errors are only detected when the LitterHopper motor rotates under specific conditions. If the Litter-Robot 4 light bar is alternating blue and purple, this indicates an error with the LitterHopper motor. You will also receive a notification on your phone if you use the Whisker app. LitterHopper errors, from most common to least common, include:

• Motor Fault Disconnected
• Motor Fault OT Amps (Motor Jammed)
• Motor Fault Short

Skip to the applicable section below according to the error in your Whisker app.

Error notification: Motor Fault Disconnected

A Motor Fault Disconnected notification indicates that the LitterHopper is not properly seated. Please follow the steps below to troubleshoot the error.

Disable the LitterHopper

1. Short press the Reset button on the Litter-Robot 4 control panel. The unit should flash WHITE and then display a solid blue light bar.
   
   
2. Disable the LitterHopper by long-pressing the Cycle and Connect buttons on the control panel for 3 seconds or tapping the "Disable" toggle button in the app.
   
   
3. Press the Power button to turn the unit off, then unplug the unit from the wall.
   

Check LitterHopper installation

1. Remove the LitterHopper by lifting it up and away from your Litter-Robot 4.
   
   
2. Check all of the following areas on the unit:
   1. Ensure there is no gap between the bonnet and the base.
      
      
   2. Ensure the bonnet hinge sits inside the base hinge pocket completely.
      
      
   3. Check and remove any dust, loose litter, or clumps from the circular pockets and the power jack. Vacuum cleaning is recommended.
      

Regularly inspect and vacuum clean the dispensing area to avoid recurrence of errors.

Reinstall the LitterHopper

1. Refer to the installation guide to reinstall the LitterHopper.
   1. Ensure there is no gap between the bottom of the LitterHopper and the Litter-Robot 4 Base.
      
      
   2. Verify the hook tab engages the slot in the bonnet.
      
      
2. Plug the unit in and power it on.
   
   
3. Litter-Robot will then perform a clean cycle and return to the Home position with the blue light on.
   
   
4. Ensure there is litter inside of the LitterHopper, then run a manual litter dispense test by long-pressing the Power and Cycle buttons simultaneously for 3 seconds.
   

Successful: If your unit dispenses litter and displays a blue light bar, re-enable the LitterHopper by long-pressing the Cycle and Connect buttons on the control panel for 3 seconds or tapping the "Enable" toggle button in the app.

Unsuccessful: If the motor does not rotate, you are still seeing a blue and purple alternating light bar, or the app displays the same error message, there's likely an issue with your LitterHopper. Skip to the "Issue not resolved?" section for assistance.

Error notification: Motor Fault OT Amps (Motor Jammed)

A Motor Fault OT Amps notification indicates a motor over-torque, likely due to an object jammed in the dispensing area. Please follow the steps below to troubleshoot the error. 

Disable the LitterHopper

1. Short press the Reset button on the Litter-Robot 4 control panel. The unit should display a solid blue light bar.
   
   
2. Disable the LitterHopper by long-pressing the Cycle and Connect buttons on the control panel for 3 seconds or by tapping the "Disable" toggle button in the app.
   
   
3. Press the Power button to turn the unit off, then unplug the unit from the wall.
   

Check for obstructions

1. To remove the LitterHopper, lift the LitterHopper up and away from your Litter-Robot 4.
   
   
2. Empty the litter from the LitterHopper.
   
   
3. Check and remove any obstructions or foreign objects from the following areas to inspect and clear the jam:
   1. The LitterHopper motor area near the flexible flaps
      
      
   2. The dispensing area inside the key
      

Reinstall the LitterHopper

1. Refer to the installation guide to reinstall the LitterHopper.
   1. Ensure there is no gap between the bottom of the LitterHopper and the Litter-Robot 4 Base.
      
   2. Verify the hook tab engages the slot in the bonnet.
      
      
2. Plug the unit in and power it on.
   
   
3. Litter-Robot will display a solid blue light indicating it is ready for use.
   
   
4. Add litter back to the LitterHopper, then run a manual litter dispense test by long-pressing the Power and Cycle buttons simultaneously for 3 seconds.
   

Successful: If your unit dispenses litter and displays a blue light bar, re-enable the LitterHopper by long-pressing the Cycle and Connect buttons on the control panel for 3 seconds or tapping the "Enable" toggle button in the app.

Unsuccessful: If the motor does not rotate, you are still seeing a blue and purple alternating light bar, or the app displays the same error message, there's likely an issue with your LitterHopper. Skip to the "Issue not resolved?" section for assistance.

Error notification: Motor Fault Short

This notification indicates there is likely an issue with the LitterHopper motor. Please follow the steps below to troubleshoot the error. 

1. Short press the Reset button on the Litter-Robot 4 control panel. The unit should display a solid blue light bar.
   
   
2. Perform a diagnostic check: 
   1. Ensure there is litter inside the LitterHopper.
      
      
   2. Run a manual litter dispense test by long-pressing the Power and Cycle buttons simultaneously for 3 seconds.
      

Successful: If your unit dispenses litter and displays a blue light bar, you’ve been successful.

Unsuccessful: If the motor does not rotate, you are still seeing a blue and purple alternating light bar, or the app displays the same error message, there's likely an issue with your LitterHopper. Skip to next section for assistance.

Issue not resolved?

Disable the LitterHopper by long-pressing the Cycle and Connect buttons on the control panel for 3 seconds or by tapping the "Disable" toggle button in the app.

Remove the LitterHopper by lifting it up and away from your Litter-Robot 4.

What do I do?

My LitterHopper is under warranty

The LitterHopper automatically includes a 1-year warranty, regardless of if your Litter-Robot 4 is still under warranty. If you purchased your Litter-Robot 4 and LitterHopper together and bought the WhiskerCare Extended Warranty, the LitterHopper will be covered under your WhiskerCare Extended Warranty. Please contact our Customer Experience Team for further assistance.

The warranty on my LitterHopper has expired

If your LitterHopper is no longer under warranty, you will need a replacement LitterHopper.

Parts Needed (choose one):

• Litter-Robot 4 LitterHopper (Coming soon) | Installation Instructions

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