Repairing a Roomba's Side Brush Module

Check on Amazon A Roomba unexpectedly came into my life.
It was pretty well-used when I got it, and after running it for a while the side brush (spinning brush) stopped working — so time to repair it.

Replacement parts

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Many robot vacuum brands are on the market these days, but one thing Roomba does better than the rest may be this: parts are available on Amazon.
Main brushes, tires, and other components are all sold individually.

Roomba seems to treat its drivetrain parts as consumables.
The internals are completely modular, and any module can be swapped out with a single screwdriver.

Of course, arguably the even better thing is that the internal API spec is publicly documented, and you can access the serial port.
But that's a story for another time.

Cleaning and reset

Getting ahead of myself there — when a drivetrain component stops working, the standard first step before replacing parts is to clean and reset it.

Flip the Roomba upside down and remove the 4 screws marked with red circles in the image below to access the internals.
Note: these screws are captive — they stay attached to the cover and can't be lost. User-friendly design from the ground up.


The interior looks like this:


You can remove each module separately: the side brush module (top left), battery, left tire module, right tire module, and center main brush module.

If something's not working, disassembling and cleaning each module can sometimes fix it on its own.
Note: the module cases use tamper-resistant screws so users don't accidentally break things by opening them. Conversely, any part using regular screws is fair game to disassemble.

After disassembling, press and hold the CLEAN button on the top center. Keep holding even after the power cuts out — eventually it will reset. Set the time and it will start working again.

Replacing the side brush module

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Cleaning and resetting didn't fix mine, so I ordered a replacement side brush module.

It arrived in this box:


…wait. The Amazon listing said "brushes shown in photo are not included" — but they were included.


Unscrew the old module, screw the new one in. That's it — repair complete.


Done in no time. The brush is spinning happily again. Oh Roomba, you adorable little robot...

I'd love to build a serial cable and try hacking the Roomba API someday.