Litter-Robot 4 Drawer Full After Emptying? What to Check

You’ve emptied the waste drawer, fitted a fresh bag and pushed it back in—but your Litter-Robot 4 still says it’s full. Start with the new liner: smooth it against the drawer’s walls and bottom, close the drawer, then press Reset, followed by Cycle. Let the cleaning cycle finish before checking the warning again.

A bag stretched across the drawer or bunched above its sides can interfere with the waste-level reading. Checking its position gives you a useful first step without throwing away another unused liner.

First, choose the right troubleshooting path

Look at the machine as well as the app. These two symptoms lead to different follow-up checks:

• Flashing blue light bar: this is the drawer-full warning. Check the contents and empty the drawer if needed. If it is already empty, follow the liner check below.
• Machine ready, but the app percentage looks too high: start with the same liner check, then use the official inaccurate waste drawer gauge guide if the reading remains wrong.

1. Refit the liner so it lies flat

Open the bag fully and wrap its edges over the drawer rim. Push the remaining material into the bottom and smooth it against the side walls. The bag should line the drawer, leaving the space where waste collects open.

Keep loose material below the top of the drawer’s sides. Once the bottom and sides lie flat, slide the drawer closed.

Does bag color matter on Litter-Robot 4?

Yes. Whisker recommends white bags for Litter-Robot 4. Dark bags can produce inaccurate waste-level readings, especially when the drawer is empty. Special branded bags are not required; fit the liner flat against the drawer’s walls and bottom.

2. Press Reset, then run a cleaning cycle

Press Reset, then press Cycle. Reset zeroes the weight sensors; the cleaning cycle lets the machine measure the waste level again. Wait for the unit to return to its home position.

For a flashing drawer-full warning, the successful result is a return home with a steady blue light bar. For an app-only problem, also check whether the displayed waste level now matches the drawer.

Still showing full?

Dust or cat hair around the sensors at the top of the opening can interfere with the reading. Follow the official drawer-full troubleshooting guide for sensor cleaning, firmware checks, obstructions and calibration. If you reach its globe-removal step, put the unit in its home position, switch it off and unplug it before removal.

Need refills?

See Stazilix bags listed for the Litter-Robot 4 waste drawer, in 100-, 150- and 200-bag packs.