Chosen Solution
What is error code 15 &31
From what i can see; Error 15 is “communication error”, and is said to be fixed by pressing the “Clean” button again or doing a restart. Error 31 appear to be “internal communication error”, this one looks unsolved tbh, or at least not publicated officially. There is this thread on reddit tho, that states; “UPDATE: I have run the Roomba S9 since removing the main vacuum head, blowing out the hair and dust: The result is that I have had very few error 31’s since. Today is the second day without an error 31. Remove the head, blow out hair and dust, put back the head and all will be well.”
31 seems to come up when any of the sensors are too dirty for operation. Clean all the sensors below and on the top of the device including the camera and the protruding cylinder thingy. This was the only thing that helped me with error 31, reboots didn’t help.
I had the same issue and ended up fixing mine. Take the entire thing apart by removing the: cleaning head, both wheel modules, battery, vacuum motor, and storage bin. I bought a can of compressed air from a office supply store and blow off every piece you removed including the main and now empty robot. Using a soft cloth and a cleaning solution (I used alcohol), clean all of the electronic connectors for the modules (the gold computer looking chips). Clean the bin sensor which a small gold color disc located behind a small black plastic piece which has to be removed near the duct for the waste bin. Put the robot back together and reset/reboot the robot. Make sure to select the option to save the map if you choose to reset it. Mine started working again after the deep cleaning. I hope this helps!
