roomba 530 spinning and stops with 9 beeps

[mfortuna]

You can measure the voltage across it and compare it to a known good PT. If the voltage differs by a substantial amount the PT is bad or is not receiving IR.

[funkadelic]

thanks, i ended up doing just that...checked the voltage of the good IR detector vs the one i replaced & ends up it was a bad solder job on my part as it wasn't registering any voltage. i think i went a little too aggressive the first time and took off part of the copper trace on the PCB but the 2nd time around I made sure the solder was good. roomba is good again! thanks everyone for the help!

[vic7767]

The condition you describe is a very common one. Glad you found and resolved your 9 beep error.

[bluetooth]

Hi
Thank you for this thread.
I had same problem, but in my case I just cleaned the hole front under the bumber and that did the job. No need for changing any diodes. I used both a small painting brush as well as a vacum cleaner.
Good luck.

[vic7767]

The two bumper sensors are sealed inside two black cases and cannot be cleaned externally using any tools like a paintbrush or vacuum cleaner.

[lainghk]

My Roomba 535 is now doing backward dancing cycle with a 1-2 sec pausing in between, no 9 beeps. I used my air compressor to blow out the sensors without completely taking the Roomba apart. Any suggestion? Thanks much in advance.

[vic7767]

To identify what is causing the behavior just run the Built In Tests.

[daddio]

I was in this forum topic (... stops with 9 beeps) some three years ago (Mar 09) and ended up replacing both bump sensors assemblies ($$$) at that time. I'm back because one of them has failed and I was curious to see if anything has become available as a rock-solid repair and/or replacement.
I have read the data-sheets for the more common replacement components for the emitter and receiver, and have not seen any specification for ‘useable lifetime hours’, or ‘half-life hours’, or whatever this behavior might fall under. There are definitely various IR emitter and receiver performance grades available, so if I go for replacing at the component level that would need consideration.
Other than increasing the value of the pull-up resistor on the detector side (from 20k to 100k or more), which could extend the useful life of what seems to be a slow decay in bump sensor IR emitter electrical performance, I haven’t seen anything.
Is there any other option besides keeping spare sensor(s) on hand for the inevitable failure(s), and spending the time needed for the disassembly, replacement and reassembly?

[vic7767]

Where did you get your parts from. I offer several solutions on my website. I've got some 500 model Roombas that are over 4 years old with the replacement bumper sensors installed that are working.

[daddio]

The sensor assemblies came from: www.protechrobotics.com
No reason for me to think they might be inferior quality.

[mfortuna]

They may have come from a parted out bot which means they are of the quality level Irobot thought was OK. That may not be the highest quality level.

[daddio]

No idea what I'll do at this point, it's getting late and I have other things to take care of, probably just order some new emitters from DigiKey or Mouser. Least expensive path, but takes more of my limited time.
Whatever I do, I'll replace both sides and get it over with while the carcass is wide open.

[ColinBlake]

Just wanted to say I had the 9 beeps problem. Tried cleaning, no luck. Read the post from Nick about switching out the resistor and hey presto, the Roomba is working fine again. That was a month ago and it's still going strong. Thanks a ton, Nick.

[peacers]

First of all thanks a lot to everyone. In particular to poleguy, Gordon and Vic7767.
I was Ready to buy a new roomba, but I found this forum and it give a second life to the device that rescued my marriage..

I decided to follow the Poleguy approach, to save considerable time. I could make the fix in little bit more than 1 h, and roomba 530 was back to work.

diagnostic:
The problem occurred about 10-15 minutes run after full charging. If you run the diagnostic in full-charged condition, there is no fault sensor report. So you have to perform the diagnostic test not o at full charged roomba to get a proper result. Probably is just enough to lose some 10mV on the +5 board supply to start the problem.

repair
Reading on R82 was giving 0.1V in steady condition. R87 was about 1V.
So I changed R87 from 20 kOhm to 82 kOhm , and I had a reading of 0.14V in steady condition.

IR-LED consideration:
I know that this quick fix will not last forever, but if the LED degradation occurs in linear way, I should have gained several 100 h of life to my roomba. By the way, I m very surprised by the original LED. On my option we cannot speak of low-cost component, but rather to a defected component or production charge, that should have been stopped by at the quality control check of the manufacturer.
I own the roomba since 3 year, and I guess that I used roomba for about 1h a day in average. This make a IR-ON period of about 1000h. This is definitely a too short life time.
3000 to 5000 h should be a reasonable life expectation for a LED to loose maximal 30% of its original luminescence .All the other IR led (i.e Cliff sensor) are working without any problem, and there is not big reports on the internet about Cliff sensors failure.

I still have a question in my mind. The proposed replacements for the IR LED are not consistent. Some leds are working on the 880nm other on the 935nm. I don’t now where is the peak sensitivity of the original photo diode, but I know that between 880 and 935 nm you can easily lost 50% of sensitivity. Someone know what is the proper matching Wavlenght of the IR replacement?

Sorry for the crappy english

Thanks in advance.

[Gordon]

...I still have a question in my mind. The proposed replacements for the IR LED are not consistent. Some leds are working on the 880nm other on the 935nm. I don’t now where is the peak sensitivity of the original photo diode, but I know that between 880 and 935 nm you can easily lost 50% of sensitivity. Someone know what is the proper matching Wavlenght of the IR replacement?...

940 nm is what I believe exists in the original equipment. The relatively narrow bandwidth of any IRED is being detected by the wide spectral response of silicon (which is the material used for the phototransistor detector in all of iRobot's optical switch arrangements). Read through this old post: http://www.robotreviews.com/chat/viewto ... 909#p58909 to see if you agree that shifting a Roomba IRED from AlGaAs (940nm) to GaAs (880nm) has a fair chance of working.

[daddio]

I finally replaced emitters on both sides, and only the emitters, with OP140A (935nm), only issue was that OP140A was slightly taller than what was being replaced, however, that does not seem to have hurt operation.

Roomba has not has any repeat of this problem with the OP140a emitters, but then I only run once a week for about 1 hour/run.

My personal reccomendation after my experience would be to replace both the reciever (transistor) and the emitter (diode) as a pair, as it is not too much more of an added expense, it is not too much more time to replace if you are replacing the emitter(s), and you will be assured that the physical and electrical characteristics match.

[peacers]

You right Gordon, i searched again for Sensitivity curves, and i found that usual PD are not so selective on the Wavelenght. you could loose maybe 10%-20% with a mismatch, but it should no matter with a proper IR emitter even if the output decay of some 10% over a lifespan of 3000 to 5000 h.
When i will disassemble the sensor i will maybe do some research on the sensitivity of the PD in function of the emitter-current.

[horseshowdad]

This is a substantial thread and thanks to all who contribute. I have two roombas 535's I believe (one mine and one a friends) who are reporting the right bumper is actuated on manual test #2. I'm not at all familar with messing with diodes, ir's, circuits boards, etc but I have gone into one of them (via instructions from Morgan from page 1 and inspected, straightened, etc the bump sensor with no luck.

Here's my question, can I take the emitter and sensor from the left bump sensor and put it in the right - thus cannibalizing one roomba for the other. If it works, I may order a new pair of sensors to put in (any suggestions from where?).

Again, thanks for your help!

[vic7767]

I offer several solution to your 535 issue, head over here and take a look:
http://www.vic7767.com/run-around-roomb ... -of-death/

[forgottenpassword]

If anybody is not comfortable using a soldering iron or if you don't have a soldering iron, there are now solder less solutions. Just need to google "solder free solution 9 beep error".