Why is my self-cleaning litter box drum not turning?

The drum stops partway, jams or strains under heavy litter

The Litter-Robot 4 manual says that if the globe becomes jammed or overloaded, the motor stops and backs up for 5 seconds, pauses 2 seconds and tries again.¹

After three failed attempts the globe stops and the light bar shows red with partial yellow flashing, which the manual calls motor obstruction or jamming.¹²

1. Litter-Robot 4: turn the unit off, remove the bonnet and the globe, and check the gear and motor for anything in the way.¹
2. Litter-Robot 4: when you put the globe back, seat the back of the globe fully in its rear bearing pocket so the gear track meets the motor pinion.⁵
3. Litter-Robot 4: check the litter level. The manual says to fill only to the raised MAX Fill Line, about 3.6 to 4.5 kg, and not to overfill.¹⁶
4. Litter-Robot 4: power on and let it cycle. If the error comes back, contact Whisker Customer Experience.¹
5. Neakasa M1: a blocked litter chamber motor shows on the indicator lights. Remove the left or right chamber cover and look for an object stuck in the gear; clean it out or contact customer service.⁴
6. Neakasa M1: keep litter between 50% and 100% of the scale. The manual lists too much litter as its own fault.⁴
7. PETKIT Pura Max: do not fill past the MAX line, and use litter shorter than 1.2 cm with a diameter under 3 mm.⁷

The drum will not start because a cover, lock or knob is open

1. Litter-Robot 4: with the bonnet off, the globe does not turn. A flashing yellow light bar means the bonnet is off; the unit resumes 5 seconds after you put it back.¹²
2. PETKIT Pura Max: if the screen shows the cylinder lock fault, PETKIT says to turn the knob on the back of the unit until the cylinder locks.³
3. Neakasa M1: a steady red light for the chamber cover means the left or right fixed cover is missing or not seated. Install it or press it fully into place.⁴

A sensor is stuck or the box thinks a cat is inside

The Litter-Robot 4 manual says the globe stops when a curtain sensor or the weight scale detects a cat during a cycle, and starts again 15 seconds after the cat is gone.⁸

1. Litter-Robot 4: if the unit is not cycling, clear fur and dust from the bezel and the curtain sensor holes with a dry towel.⁸
2. Litter-Robot 4: press Reset to zero the weight scale after adding litter, emptying the drawer, cleaning or moving the unit.⁹⁸
3. Litter-Robot 4: blue light with partial yellow flashing means extra weight for more than 30 minutes. Place the unit on a hard, level floor, not touching walls, with mats in front of it rather than under it.²⁶⁸
4. PETKIT Pura Max: the box pauses when a cat comes near during a cycle. Wipe the proximity sensor clean, and note that the app's Rotation without interruption setting keeps it turning.³¹⁰¹¹
5. PETKIT Pura Max: lift and set the unit down gently to protect the weight sensor underneath, and keep it on a level surface away from the wall.¹²
6. Neakasa M1: yellow blinking means a cat interrupted the cycle. Wait for the cat to leave; the manual says the machine resumes after about 1 minute.⁴
7. Neakasa M1: a blinking red Clean light means the weight sensor is overloaded. Remove any objects in the box. All five lights blinking red is a weighing sensor error: unplug, restart, and contact customer service if it continues.⁴

The pinch sensor keeps stopping the drum

The Litter-Robot 4 manual says anti-pinch sensors sit on each side of the chute into the waste drawer. If they sense a pinch, the globe backs up for 5 seconds and the light bar shows a yellow ping-pong pattern.¹

1. Litter-Robot 4: remove whatever is in the way, and keep the dual pinch bars clear of excess litter when you fit a new drawer liner.¹

The waste drawer is full or overflowing

The Litter-Robot 4 manual says a flashing blue light bar means the drawer is full. On the third full signal the cat sensors switch off and the unit stops cycling on its own.¹³²

1. Litter-Robot 4: empty the drawer, press Reset to clear the signal, then press Reset again to zero the scale.¹³
2. Litter-Robot 4: when you slide the drawer back, do not push the unit against a wall or into a corner.⁹
3. Neakasa M1: a red Empty light means the bin is full, the bag is set badly, or the bin is not in place. Empty it, fit a new bag, and push the bin fully in.⁴
4. Neakasa M1: a loose fold of the trash bag can block the internal infrared sensor and cause the red light. Smooth the bag out.¹⁴
5. Neakasa M1: before dumping all litter, check the bin has room, or the door may stick. If it does, pull the bin out slowly, move it back and forth 4 to 5 times, then pull it out again.¹⁴

The screen is not separating clumps

1. Litter-Robot 4: use a clumping litter. The manual says non-clumping, loose-clumping, newspaper and wood pellet litters do not work.⁶
2. Litter-Robot 4: if clumps are not ready when the cycle starts, lengthen the Cycle Delay. The manual suggests this for lower-quality clumping litter.¹⁵
3. PETKIT Pura Max: after cleaning, refit the litter sifter at points a and b. The manual says it is fitted right when the screen can be shaken back and forth.¹¹

When to contact the manufacturer

• Whisker tells Litter-Robot 4 owners to contact Customer Experience if the jam error persists, and points to whiskersupport.com for troubleshooting. A red light with partial white flashing also means contact Customer Experience.¹¹⁶²
• Whisker lists a 1-year warranty on the Litter-Robot 4 product page, and the manual describes a 90-day in-home trial.¹⁷¹⁶
• The PETKIT manual says to check the detailed fault in the app and to contact customer service for any issue.³¹²
• The Neakasa M1 manual sends you to customer service when a cleared gear, door or weight-sensor fault does not go away. Neakasa lists a 2-year limited warranty.⁴¹⁸