Question about iRobot Roomba 4210 Bagless Robotic Vacuum

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I robot discovery

My i robot keeps on going backwards and keeps on circling

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Re: i robot discovery

I have takin several Roombas apart with this problem. Basically the sensors on the bumber are blocked so the roomba thinks it is hitting something. I believe this is a design problem because it is so common. If you could see how the bumbers work, there is an infrared sending unit and an infrared receiving unit (they look like little LED's. when the bumper is pressed, a plastic piece moves between the two infrared led's blocking the transmission. This signals roomba to stop and backup. What happens over time is the sending led thing gets dislodged and moves slightly. The receiving led can't sense the signal so it thinks the bumper is depressed.

Hard to explain, but I have fixed the problem by shimming the led back in place and worst case, I drilled the hole in the plastic piece a little larger. Solved the problem and I have recaimed several roombas that were considered scrap. Irobot should fess up to this known problem and issue a fix for everyone of the defective units.

Posted on Mar 06, 2009

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Re: i robot discovery

This is a very common problem with this machine. It's little electronic brain is in spasm. There is a 1-800 number on the bottom of the machine and will connect you with the manufacturer. They have a fix for it and you should NOT explore further. These electronics are very sensitive and you can damage them very easily.

Posted on Jan 20, 2008

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