Roomba 5XX 9 beep error still after replacing sensors

Help & Support Domestic Robots
1

Hi,

I apologize if this has been covered in another thread but when I searched I couldn’t find anything relating to this particular issue.

First off, I’ve read a lot about the 9 beep error. I thought I knew a lot about the issue and it seemed like a simple fix so I purchased a bot from eBay as a for parts/not working unit. The seller said it would drive back and forth for 20 seconds and then die. Seemed to me like it needed a new battery and then some new sensors. Battery replaced just fine and this allowed it to run for a normal amount of time and for me to test it. When ran it gave the 9 beep error after doing its little dance.

Did the test to confirm the bumper sensors were at fault. (Held dock+clean and pressed spot six times, advanced to test two, pressed L/R bumpers) Once into test two, and throughout me pressing them, they spot/dock buttons were constantly lit and the clean button was red. In my admittedly limited experience this meant to be that both bumper sensors were bad. I ordered the specific ir emitter and receivers from digikey after finding the specific parts #s from another thread and replaced both on both sides.

At this point it is worth noting that during the initial tests the buttons on top were sticky. When I took it apart it looked like something, cola?, had been spilled on the top of the roomba and dripped down into it. There was some very very minimal sticky residue beneath the button cluster that made its way onto the protective plastic film and the occasional drip onto the MoBo, but nothing too awful looking. I cleaned all of this very carefully with high % alcohol and q-tips.

I reassembled everything and turned it back on and still get the nine beep error. Spot/dock both still illuminated when going thru the motions of the test.

I’m going to tear it back down again tomorrow and see if there is anything I overlooked but I’m pretty meticulous and doubt this is my issue. I want to know if any of you guys have experienced something similar to this and if so how I should proceed. Are there more reasons I could be getting the nine beep error other than a faulty sensor? Could whatever it was that dripped have possibly ruined the bumper sensor circuit on the main board? I checked all the wires and none of them looked frayed/arced/stripped or otherwise damaged.

I ordered multiple IR emitters and receivers (was actually cheaper if I ordered ten of each instead of two), and was contemplating just replacing them all again because you know, definition of insanity and whatnot.

Have I overlooked something or is there an additional test anyone can recommend?

I appreciate all the help!

2

@Nsykora,
It can be an error with the motherboard at this point. We suggest you to try replacing it.

3

Thanks for the response. I understand that replacing the main board is a logical assumption but it seems like replacing things at random and hoping for it to work is a bit misguided and can get costly. I started this project with the hope of keeping the costs as minimal as possible and purchased the bot for only $50 and working boards I’ve found are nearly that much making this cost ineffective.

Is there any additional testing I can do prior to simply replacing the entire board? I’m pretty handy with electronics and have basic tools including a multimeter.

4

UPDATE 6/14/17

So apparently I’m not as good as I thought. I went through the motions again and determined that, in conjunction with sub par harbor freight tools that were literally melting only slightly slower than my solder, my soldering was absolute ■■■■■■ I went through the motions and replaced all the sensors again and re-ran the test. At this time it showed the right bumper was working but the left still was not. I took it apart yet again and noticed I shorted it out with my previous soldering near the top of the board. Quickly rectified that and voila, the roomba lives again!!