Error code C

Last updated: August 8, 2026
Applicable model: Popur S7 Split Litter System (SLS)
Applicable firmware version: 4.0.0 & onwards
Applicable mobile app version: 2.0.0 & onwards (both Android & iOS)

🔍 Troubleshooting Suggestions

Error code C indicates that the angular sensor for the rotor unit is glitchy. The rotor unit may be found continuing its rotation despite that it has already reached its maximum angle relative to the litter tray, leading to clunky movements. In tandem with this code, the status light will also turn into the solid red color.

Thanks to S7's built-in redundancy, typically this issue can be resolved by taking the following steps in order to activate a backup sensor:

  1. Activate the Pro-Commands mode by holding the Fn button for 7 seconds till you hear three short beeps, and the status light will turn blue;
  2. Then, hold the Clean/Play button for 3 seconds till you hear a prolonged beep;
  3. Wait briefly for 3 to 5 seconds till another prolonged beep, which means complete;
  4. Reboot the machine or exit the Pro-Commands by holding the Fn button for 7s again.

The duplicate sensor will engage after these steps, and the unit is expected to work properly again. Otherwise, reboot the machine or perform the self-check again. If the rotation is still incorrect or the solid red light recurs, a new motherboard will be needed.

Note: If you try to activate the Pro-Commands after the machine is just powered up, it'll automatically pause the initialization sequence. If you've customized the Fn button and therefore the Pro-Commands cannot be triggered by the Fn button, you may change the customization or conduct a hard reset to restore the settings.

🪛 Repair or Replacement

We recommend replacing the motherboard to permanently resolve the issue if this error code appears. Feel free to keep the cat sensor as backup and skip the corresponding section in the video, as it is not applicable to the present issue.

For the replacement parts:

Warm reminder: If you don't hear from us within 48 hours, it suggests that your email provider has spammed or blocked our reply. Please add our domain (@popur.com) to your approved senders list or check the junk folder. You may go ahead purchase the above parts first to save shipping time, and ask for a refund retrospectively. Please note this type of refund can only be issued via non-expiring store credit as a warranty arrangement.

🚩 Special Case for Incompatible Software after Replacement

If the new motherboard you received is baked with firmware 3.6.0 or earlier version, it will be incompatible with the rest of the system, as well as App 2.0.0 version. You can tell this info in the Popur S7 App → Device Page → Top-right icon for Settings → Technical info.

While the core functions including auto-clean remains intact, a suite of new features won't work.

To address this incompatibility, simply update to firmware 4.0.0 or onwards in the Popur S7 App → Device Page → Top-right icon for Settings → Firmware update.