HP Notebook - 17-by0020cy Keyboard Backlight?

[GSStechnology]

I am working on a customer's HP Notebook - 17-by0020cy and I replaced the palmrest/keyboard because the customer claimed that the backlight did not function. The replacement keyboard's backlight also does not work, so I am wondering if the unit had a backlit keyboard in the first place. Thank you!

[Paul_Tikkanen]

According to the specs, it indicates the notebook came with a backlit keyboard.

Keyboard

Full-size island-style backlit keyboard with numeric keypad

Since those specs were not 'official' HP specs, I looked at the parts list for the product number and it confirms that the notebook came with a backlit keyboard but you can't just replace the keyboard as it is part of the top cover assembly.

HP PartSurfer

L22749-001

TOP COVER AHS W/TP W/KB AHS BL US

[GSStechnology]

With the new keyboard, how do I enable the backlight? I tried several key combinations involving the backlight key in the function row. Is there a setting in the BIOS or Windows that I am missing? The replacement keyboard is a brand new part and I double checked all of the connections. 

[Paul_Tikkanen]

If you bought the top cover/keyboard part number I posted yesterday (the only one that's going to work), the F4 key has a keyboard icon with 'light rays' above the keyboard icon.

Pressing the F4 key enables the backlight.

If the F4 key does not have that icon, then you didn't install a backlit keyboard.

On some model notebooks you press the Fn + F4 key.

[GSStechnology]

Our new keyboard has the correct button and it does not turn on the backlight when presses, even if it is pressed in conjunction with the Fn key. We have updated drivers and Windows. Is there a setting somewhere I am missing? How is it enabled?

[Paul_Tikkanen]

Unfortunately, I wouldn't know what the problem could be. 

On my HP notebook, I turn on the backlight by pressing the F4 key.

My notebook's F4 key has 3 actions: bright, less bright and off.

[GSStechnology]

We checked BIOS - nothing there to control backlight

Un-installed and re-installed kb drivers

Updated firmware - chipset

Replaced palmiest

[GSStechnology · Accepted solution]

Found the solution:
The new palmrest had a 2nd ribbon cable tucked away that wasn't plugged in. Once plugged in, the backlight Immediately turned on.