HP 450 G5 - keyboard problem

[CornholioGSM]

Hello,
i have here ex water smashed 450 g5 with mainboard da0x8cmb6e0.
Water was mainly on and around kbc npce586ha2mx.
KBC was desoldered, all cleaned and soldered back...on leg was repaired under microscope.
Problem is, that some keys on kb wont work correctly - for example when i press "O" laptop turns on airplane mode.
...problem still with connected external keyboard. at first it seemed like keyboard problem...but i have tested another two 100% working keyboards and problem still.
When is internal keyboard disconnected and is connected only usb kb then all works fine.

I was not able to find service manual for this laptop.

Soo what you mean? is needed to change kbc npce586ha2mx ?

thx

[emestee]

Re: HP 450 G5 - keyboard problem

The keyboard connector data lines go directly to the EC. You may want to test them one by one. Find schematics for a board with the same EC, keyboard lines are defined by EC hardware and pinout doesn't change between boards.

Another alternative would be something silly like Fn function being on by default.

[CornholioGSM]

Re: HP 450 G5 - keyboard problem

...this ec is needed to be programmed or can i use directly another desoldered from another mainboard?

[emestee]

Re: HP 450 G5 - keyboard problem

...this ec is needed to be programmed or can i use directly another desoldered from another mainboard?

If I remember correctly from seeing it elsewhere, but dont quote me on it, it's self-programming - a blank EC would load its firmware from a SPI flash and store it internally. Quick google suggests it has nasty security features too.

[SMDFlea]

Re: HP 450 G5 - keyboard problem

If I remember correctly from seeing it elsewhere, but dont quote me on it, it's self-programming - a blank EC would load its firmware from a SPI flash and store it internally. Quick google suggests it has nasty security features too.

Edit: website in french language: https://www.ssi.gouv.fr/entreprise/c...-npce576ha2yx/

Does it mean it can only be replaced with one from a donor board .

[emestee]

Re: HP 450 G5 - keyboard problem

Does it mean it can only be replaced with one from a donor board .

I don't think so. If anything, installing a programmed one from a donor board is probably a bad idea if it has security features enabled. There's simply no documentation on it. The russian engineers claimed to have made some progress, JTAG was mentioned but it's hush hush so far, so we don't have any data. There are supposedly EC dumps but I dont have access to them.

Edit: upon some more googling tl;dr this EC is bad news. It is presumed to have unique OTP programming keys and so nothing to be done with it except replacement from an identical donor.

[emestee]

Re: HP 450 G5 - keyboard problem

Ok here's some good news. The previous revision of this machine (Quanta X93A) has the same KBC. There's a reported case on russian forums where this KBC was successfully replaced with the 781 variant, and the bios was replaced with 25q80 or 25q128. The flashed BIOS was the official one with serial numbers copied from the original.

Source (Russian): http://********/viewtopic.php?f=53&t=80018

[CornholioGSM]

Re: HP 450 G5 - keyboard problem

soo what will be the simplest solution? buy new one from ali etc...then it will be self programmed from spi?

[emestee]

Re: HP 450 G5 - keyboard problem

I would highly suggest you prove affirmatively that this is a KBC issue before trying to replace it.

[CornholioGSM]

Re: HP 450 G5 (da0x8cmb6e0) - keyboard problem

*SOLVED*
...i have found mainboard from 470 G5 ( 17" version with dGPU). ...soo i have changed kbc from this mainboard and all works fine without programming

[mcplslg123]

Re: HP 450 G5 (da0x8cmb6e0) - keyboard problem

*SOLVED*
...i have found mainboard from 470 G5 ( 17" version with dGPU). ...soo i have changed kbc from this mainboard and all works fine without programming

Was the mb number same in 450 G5/470 G5??

[CornholioGSM]

Re: HP 450 G5 - keyboard problem

nono little different...give me few hours i will post it

[CornholioGSM]

Re: HP 450 G5 - keyboard problem

...sorry my error...mainboard was same mb number - only with dGPU

[mcplslg123]

Re: HP 450 G5 - keyboard problem

...sorry my error...mainboard was same mb number - only with dGPU

Hmm. So that leaves us still confused whether this kbc can be replaced from different mb. Will try to dig it and update if anything interesting found. I've not replaced this kbc so far and that's why want to know more.

[reformatt]

I just had a liquid damaged 430 G5 in. There are no schematics for the DA0X8BMB6G0 board; the DA0X8BMB6F0 board is basically the same design, albeit with components in different locations. Connections from the EC to the keyboard connector are the same (although the silkscreen has pin 1 at the wrong end).

Water spilt in the left side of the keyboard. It only affected the small daughterboard (which has a USB connector and the power button flex passes through it). Some corrosion on the connector from that board to the motherboard had corrosion on it, causing the machine to come on, then go straight off. However, after fixing that, keyboard not working, even with a new one. Keyboard connector etc buzzed out so I replaced the EC (NPCE586HA2MX) from some I got a while back from China. Can confirm this works without programming and keyboard now working ok. The water in the keyboard did indeed damage the EC, which was a bit surprising. There is no EC code in the BIOS, or a connected SPI ROM, so I'm thinking the functions of this IC are hard coded.

BTW, did have a screw up with the power LED not working after the EC replacement (I did have the power button hanging loose detached from the palmrest during troubleshooting). As there aren't any schematics, had to sit and buzz this out. To save others time, power LED should be an active low from pin 115 of the EC. This is connected to pin 5 of the 2N2007DW (K27) dual FET that is right next to that daughterboard connector. Pin 6 is the output and goes to pin 2 of the daughterboard connector. Replacing this FET fixed that fault. I guess this shorted when hanging free during troubleshooting. Wasted a good hour or so on this.