Roomba 560 9 beep error test and fix

How to test and fix 9 beep / bumber error.
Some video clips and photos I put together while learning how to use OpenShot video editor.
I didn't include any photos/video how to disassemble a Roomba, because there's a lot of tutorials how to do it. Just be careful while opening bumber housing to not drop the axel or spring from the bumber arm.
The led I used was OP140A, that I found from Elfa.
One thing I forgot to mention in the video is, that the leds lens should point towards receiver.
Update...
List of compatible leds can be found here: www.schneordesign.com/Avi/irob...

[@poppylover2586]

I like how the roomba did an ascending descending melody when you pressed dock and clean

[@jimmmora12]

as a pointer, make sure the unit is "off" before holding down the Clean and Dock buttons. To Turn off, hold down the clean button until it turns off.

[@yugolago]

where can we get those ir-led ? and do we have to replace all of them?

[@ArhPos]

After a lot of struggle, I put a link to description.

[@Freizeitschranzer]

My old roomba 530 dows only test the two bumper sensors, NOT the ir leds!!

[@audrey3297]

Merci!

[@charliedavisthearchitect3874]

WOW

[@kinglord5429]

I ran the test and it seams roomba is blind on one side, keeps moving the dock around but have no error codes. Seams started when we replaced the old battery with new extra long time battery. Roomba has become a monster knocking things around in front of it.