Litter-Robot II Repair Guide – Chapter 5: Sensor Harness | RobotShop Community

This guide will help you with the replacement of the Litter-Robot sensor harness. This is chapter 5 of the RobotShop Litter-Robot II repair guides.

This is a companion discussion topic for the original entry at

What does the Hall Effect Sensor do?

@Cahrles The Hall Effect sensor is used to detect the position of the globe. For example, if the globe rotates a full 360 degrees anti-clock wise, the hall effect sensor will send a signal to the motherboard saying that there is something wrong with the position of the globe. Normally, it is supposed to rotate a little more then half way a turn anti-clock wise.

Hi, the cleaning cycle goes wrong. When the globe go to the “open” position (anti-clock wise) it works fine. The globe rotates to the right position and stop. After that, it is trying to go back to waiting position (clock wise rotation) but it does not stop at the right place. It goes a quarter too much (than it was doing yesterday) and go back some degrees, But the door is not in the right position. After that the three leds start blinking together slowly. I have changed the harnes and the hall effect sensor, i have changed the electronic card… but the problem is still here. An idea of what i can check ? It was working fine yesterday, i don’t understand what could be the problem.

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@mtregael, Please try the following troubleshooting tips. HERE
If it doesn’t work, you may have to replace the power supply, also. Please read the following explanation from the manufacturer. HERE

What would cause the globe to rotate in the wrong direction all of a sudden?! I reversed the polarity at the motor connections and now it runs CCW/CW as it should. However, it still has a location issue, and at the dump position it will “drive right over” the stop for the flaps actuating pin! Is the Hall sensor faulty, or the magnets in the globe? Control board whacked?!?

So I am curious about what pulses the Hall sensor-is it picking up the drive gear and the ECU “counts” to reckon where the globe is at? Or is it in the globe itself? My globe is rotating past the dump spot in the CCW mode…Not sure if I should buy both an ECU AND a sensor harness and will you accept a return of what is not needed?!?

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@Matthew Hansen Hi, the problem can be caused by either the hall effect sensor, which triggers on magnets inside the globe, or a defective safety line sensor. You can certainly purchase the parts you think you need and contact us via our support center to proceed with the return of what is not needed.


My litter robot II was not spinning the globe in the correct location and was not ending the cycle in the right spot. After taking it apart, it looked like various parts could use replacing. I replaced the motor, sensor harness to include hall sensor, and the cat-detecting sensor. It is not spinning correctly, however, it stops the spin right before it triggers the dump, so it isn’t dumping the litter as it should. It spins back and ends at the right spot correctly. What else could be going on?

we suggest you contact us via the support center for further troubleshooting. Also, if you may join a video of the unit in cycle, it would help our team to identify the source of the issue.

I just replaced the harness, motor, and circuit board in my LR2 and now there is red flashing light.

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Hi @Gilgamesh

If there is a red flashing light, you should check the cat sensor.