Thanks to reading through previous posts on this forum, I have come to the conclusion that my trusty Pet Series roomba has either a bumper sensor problem or potentially a bad wheel drive circuit on the motherboard. It is doing the spin-in-clockwise circles before giving Error 9. Following the disassembly manual posted here, I took the robot apart and thoroughly blew out all the crevices with compressed gas. I reassembled it, but the problem remained.
Is it likely for the sensor circuit board to go bad after 2 years? I’d prefer not to replace it if the answer is actually in the mother board. On the other hand, in poking around in the store here it doesn’t look like buying a replacement motherboard is an option? I found bumper sensor array and the replacement IR sensor board easily enough, and the older posts here seemed to indicate its possible to buy the motherboard here.
Assuming it is possible, what procedures could I do to distinguish between the bad sensor board and bad motherboard
If your robot is turning in circles and is giving you the 9 beep error code, we suggest to replace the two bumper sensors. This problem usually does not come from the motherboard but, from the sensors themselves.
You can find the replacement bumper sensors here.
We also have a manual for easy replacement.