Thinkpad L460 NM-A651 Keyboard Problems

[Inforgalaxie]

Hi, I have a Notebook that have a keyboard problem.
Some principal keys not corresponding.
Example:

key Esc on keyboard -- > is a space
key Space on keyboard -- >is Enter
key up arrow on keyboard --> is a down arrow

I change the keyboard and the problem is the same.

With a USB keyboard all keys work fine.

It can be keyboard Matrix circuit problem...

[SMDFlea]

Re: Keyboard Problems

What is the laptop model number and motherboard part number. If there is a schematic available post a link to it.

.

[Inforgalaxie]

Re: Keyboard Problems

Lenovo Thinkpad L460

Board: BL460 NM-A651
2015-10-26
REV 1.0

Schematic -> https://www.badcaps.net/forum/showthread.php?t=85725
.

[Inforgalaxie]

Re: Thinkpad L460 NM-A651 Keyboard Problems

What you think?

[mon2]

Re: Thinkpad L460 NM-A651 Keyboard Problems

Confirm there is no damage or lifted pads on the actual keyboard connector @ JKB1. Confirm the solder joints are solid and without corrosion. Clean with IPA (alcohol) to be sure.

Assuming the keyboards being tested are compatible with the logic board, check that each GPIO pin used for the keyboard scan function are not damaged.

Remove all power. Meter in DIODE mode.

Red meter probe, yes red to ground.
Black meter probe to the pin to test.

Test each KSxx pin in diode mode and post each measurement.

Suggest to test this group of pins without your keyboard connected and then again, with the keyboard connected.

[Inforgalaxie]

Re: Thinkpad L460 NM-A651 Keyboard Problems

Multimeter in Diode Mode
Red meter probe on ground and Black to te PIN

Measurement without Keyboard:

PIN1- 720
PIN2 - 720
PIN3 - 720
PIN4 - 706
PIN5 - 720
PIN6 - 719
PIN7 - 709
PIN8 - 709
PIN10 - 709
PIN11 - 705
PIN12 - 718
PIN13 - 704
PIN14 - 704
PIN15 - 708
PIN16 - 706
PIN17 - 706
PIN18 - 706
PIN19 - 708
PIN20 - 709
PIN21 - 709
PIN22 - 709
PIN23 - 709
PIN24 - 709
PIN25 - 635
PIN26 - 527
PIN27 - 530
PIN28 - 532
PIN29 - 578
PIN30 - 0
PIN31 - 706
PIN32 - 709

With Keyboard connected the Measurement is the same.

[Inforgalaxie]

Re: Thinkpad L460 NM-A651 Keyboard Problems

what you think? Need Programming the IT8586E ?

[maxsim86]

Re: Thinkpad L460 NM-A651 Keyboard Problems

https://support.lenovo.com/sa/en/sol...s-may-not-work

[Inforgalaxie]

Re: Thinkpad L460 NM-A651 Keyboard Problems

It is not windows OS problem.
USB Keyboard Works Fine.
For example If i go to the BIOS setup the arrows keys not corresponding. If i click right Arrow on Keyboard It corresponding Go down in BIOS setup. Só its the EC SIO Controller problem..

[Inforgalaxie]

Re: Thinkpad L460 NM-A651 Keyboard Problems

Programming EC its a solution what you think?

[mon2]

Re: Thinkpad L460 NM-A651 Keyboard Problems

Yes, try it and post your updates.

What is the history of this unit?