HP flow M525 pullout keyboard

[tech07]

I have 2 of these models with a pullout keyboard that are exhibiting the same issue. The keyboards are not functioning at all.
Using the push button on the back of display, the keyboard shows as being installed, but that's it.
I have replaced the keyboard and even the display unit and also updated the firmware.
Still no response.
Any idea what I may be missing ?
Could a recent software update be the culprit ?
I don't suspect the formatter board and don"t THROW parts at machines.
2 machines. Same symptom. Same time.

 

[RepairTool92]

did you have a power outage recently ?

what you're describing is extremely rare for two machines to exhibit the exact same problem at the same time. it sounds like you had a power surge or something and it fried your boards. I would try replacing the dc controller