Keyboard still not working on HP 15 Notebook PC - Replaced non-functioning one w/ new

[Chip195]

Just replaced a failed 500Gb hard drive on a friend's HP 15-f019dx Notebook J9M33UA. While apart, I noticed the keyboard had something sticky spilled in it (didn't know if it worked from the start). Attempted to clean carefully w/ alcohol & put everything back together. No keyboard keys would work though the touchpad worked OK. Borrowed a USB keyboard to continue the software installation which worked OK. Purchased a new Windows 10 Home Full Version license & Microsoft Office Home & Student 2016 license and installed. Using HP Support Assistant, updated all drivers. Downloaded numerous Windows 10  related updates & rebooted numerous times. Everything is working fine except the keyboard. Ordered & received a new HP #776778-001 keyboard & installed. Keyboard still not working... Ribbon appears installed OK. Tried to run the HP PC Hardware Diagnostics UEFI software (F2 @ boot) to test the keyboard component but only "Memory Test", "Hard Drive Check" & "Language" are listed, not the graphical version I expected from the HP support website. The UEFI version is 1.6.0.0 - BIOS. I had previously downloaded this diagnostic tool from the HP support website. The BIOS version currently shows F.23, vendor Insyde. 

Can someone help me troubleshoot why the new keyboard is not working?

[Chip195]

By the way, I uninstalled & reinstalled the Standard PS/2 keyboard driver with no luck on gaining keyboard function. It says the "This device is working properly". Driver version is 10.0.15063.0 dated 6/21/2006 (WinBuild. 160101.0800). 

Just looking under Settings, Bluetooth & Other Devices, Mouse, Keyboard & Pen and it shows "Dell USB Keyboard" which I am using to get by for now.

Can someone help me troubleshoot this non-functioning keyboard problem?

[Chip195 · Accepted solution]

Found that the new keyboard's ribbon cable was missing the alignment nubs on each side like the original one had. When I put the ribbon cable in the connector the ribbon circuits weren't aligned with the contact wires in the connector therefore nothing on the keyboard worked.

Before I resolved the problem, I downloaded many of the HP 15 software drivers & updated them including updating the BIOS from F.23 to F.36 & the HP PC Hardware Diagnostics UEFI from a text base screen to the graphical interface.

Everything works OK now and I sure learned a lot!