Bluetooth will not pair with Lenovo Bluetooth Keyboard

[Steve Cohen]

Ubuntu 14.04
Lenovo Thinkpad T540P and Lenovo KT1255 bluetooth keyboard

With bluetooth turned on, turn on keyboard and search for devices. Device is quickly found. Try to pair with it. A six digit random number is generated by the software with instructions to type it on the keyboard and press enter. Always fails to pair although the number is typed correctly.

[cbsuh (cbsuh)]

I've succeeded pairing Lenovo KT1255 - Thinkpad compact bluetooth keyboard with trackpoint.

https://bugzilla.redhat.com/show_bug.cgi?id=1019287

I followed 'comment 3' since the method in 'comment 2' didn't work.
I realized that passcode in UI is wrong one, so you cannot authenticate with that passcode. Use passcode from hcidump.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Yura (ykuchinskiy)]

Thank you cbsuh. I confirm the fix for the same issue on the following HW/SW:
Ubuntu 14.04
Lenovo ThinkPad bluethooth keyboard KT-1255
Lenovo ThinkPad Helix

[Eike (e-h-juerrens)]

I can confirm that the bug still exists.

System:
ubuntu 17.10 artful

Packages:
- gnome-bluetooth 3.26.1-1
- libbluetooth3:amd64 5.46-0ubuntu3
- gir1.2-gnomebluetooth-1.0:amd64 3.26.1-1
- libgnome-bluetooth13:amd64 3.26.1-1
- pulseaudio-module-bluetooth 1:10.0-2ubuntu3

Hardware:
Lenovo ThinkPad T470p

[Marcelo (marparcepelopo)]

I get it resolved this way in my Ubuntu 18.04.2 LTS. I followed up the link posted before by cbsuh in the first comment but I can show you how to pair it quickly and safe:

Be sure you have the tool hcidump installed. If don't, sudo apt install bluez-hcidump

Run hcitool scan and search for your device.
In my case:
hcitool scan
Scanning ...
 XX:XX:XX:XX:XX:XX ThinkPad Compact Bluetooth Keyboard with TrackPoint

Next, run "sudo hcidump -at | grep -i passkey" and wait till you see the line with the passcode you'll have to enter with your keyboard and press enter.

Now, go to your Bluetooth devices list (when you see your device listed), and after select it, choose Setup, Pair device and Next (in the dialogue)

After a few seconds later, you will see the passcode number so enter it quickly and press Enter. You have to slide the lid of the right several times to put the keyboard in Discoverable mode.
For me, it did not work at first time, but yes at the second time.

In my case:
sudo hcidump -at|grep -i passkey
    bdaddr XX:XX:XX:XX:XX:XX passkey 159066

The command prints out a lot of output, so with the grep you only pay attention to what's important.

And, now it's paired.