Hey! I picked up a malfunctioning robovac 11 that a neighbor was offloading for free, and so it's my problem now.

I'm taking a look at it, and it doesn't want to run for more than a couple of seconds. It far prefers to go backwards a little bit, then rotate 180°, then two-tone beep and stop. If I try the manual controls on the remote, the only button which seems to do anything is 'down', which it responds to for a moment before stopping again.

The status LED is in the 'breathing blue' mode no matter what I do: the manual says this means the robovac is charging ... but it's breathing blue regardless of whether the vac is connected to power, or in the dock, or standing free. It remains breathing blue even if the hard switch is set to "off".

It never gives me a red light, so I guess the obvious error codes don't apply. The device is clean: bumpers, surfaces, etc, have been wiped. I've stripped the unit down part way, expecting I'd find some obvious dirt or a loose connection, but it's pretty clean all over and seems in good condition. There are scuff marks underneath from use, but the brushes are clean or new, and the wheels move freely.

My question, for people who know about these units: is this a known behavior with a known resolution? Is the battery a dud and in need of replacement? (I left it to charge overnight.) Or is there a deeper failure?