I'm switching to another keyboard. I liked this one, but even when plugged into USB the backlight will not stay on. Bye Bye Logitech.

TL;DR
I wasted time testing at the HID level. There is no supported host command to keep MX Keys’ backlight on over the Bolt receiver.
AutoHotkey/C# “fake keypress” tricks don’t help because the keyboard firmware owns the timer.
Logitech, please add an “Always on / longer timeout” setting in Options+ or publish a supported API/SDK (or HID++ docs) so we can control illumination.

What I tried:

- HID enumeration (Windows):
Only usable endpoint is the Bolt receiver interface with InLen=7 / OutLen=7 on report ID `0x10` (HID++ short channel). Other interfaces: no I/O reports or FeatLen=0.
- Direct HID++ probes:
Every write returns an error frame from the receiver like:

IN: 10 FF 8F 00 00 01 00
IN: 10 0A 8F 00 00 08 00
IN: 10 02 8F 00 00 09 00

(`0x8F` = HID++ error).

Also tried a wide range of feature IDs (0x0003, 0x1000, 0x1F01, 0x1981, 0x1982, etc.). No feature responds.

- AutoHotkey / C# synthetic input:
Doesn’t reset the backlight timer. Those events never reach the keyboard’s MCU, only physical key presses or the proximity sensor do.

- Result: The backlight timeout is enforced in the keyboard firmware, and the Bolt path rejects undocumented commands (likely behind Bolt’s encrypted session).
As end-users, we’re blocked.

What would make this work:

1. Product setting (best): Add a ******* backlight timeout = Off / 5 / 10 / 30 min / Always on in Logi Options+.
Bonus: “Always on while charging/USB power.”

2. Documented control:
Publish HID++ illumination feature for MX Keys on Bolt/Bluetooth (unencrypted or with a documented, supported handshake), or ship a signed CLI/SDK (Headless Options+) we can script to set brightness/timeout.

3. At minimum: ******* reply to this thread !

Why this matters:

- Work in dark rooms, recording sessions, presentations: we need the keys lit without touching the keyboard every few seconds.
- This is a premium and ******* expensive device, basic backlight control should not be locked away!

August 2025, and the problem still hasn't been resolved.
I still can't get the backlight on my MX Keys to stay lit.
With thousands of reports in the left panel, this company just doesn't care.
According to ChatGPT (yes), the best solution is to simulate activity, then stop buying from Logitech:

"Yeah — that Logitech UserVoice thread is infuriating.

Hundreds of users have been begging for a simple setting to control or disable the MX Keys backlight timeout, and Logitech has:

- Ignored requests for years
- Shipped multiple versions of MX Keys (Mini, S) with the same limitation
- Released Logi Options+, a full-blown software suite, yet still no toggle for backlight duration

The worst part?
- It's clearly a firmware-controlled behavior, and adding a toggle in software would be trivial.

They just don’t want to — likely for:
- Battery longevity excuse
- Product segmentation (keeping "Pro" features gated)
- Or sheer lack of care

Your Best Move:
- Use an AutoHotkey script or small background tool to simulate activity
- Keep hammering that thread if you want, but it won’t change soon
- Consider alternative keyboards with full software control (e.g. Keychron Q series, Varmilo, Das Keyboard, Royal Kludge)"

You going to ever address this?

I can't believe that a simple feature like leaving the backlight on is not here...
Just bought this keyboard, and this backlight experience is horrible. For a productivity keyboard i don't need any fancy effect on the backlight, I just need it on... that is what logitech does not deliver.

Can we get a firmware update for this? I want it on ALL the time unless I explicitly turn it off.

Why include stupid breathing, wave or random modes? Just add the only important setting – that is backlight timeout.

Last time buying a Logitech keyboard with this nonsense.

Guys, they are already added timeout option for mx mini keyboards. Maybe we will see this features on fullsize mx keys in 2024 😁

Wow, wish I saw this thread BEFORE I bought the keyboard and mouse :(
Seems like this should only be 5 lines of code.

I just payed a lot of money for my MX Mechanical. I'd like to be able to control the backlight timeout length.

Why have a "uservoice" forum that you completely ignore?

Bad product managers, not listening to their customers.

Logitech have put "Planned" next to another idea about this but that was 2 years ago! At this rate we'll have GTA 6 before we can keep the backlight on on a keyboard. COME ON LOGITECH, WE JUST WANT TO EXTEND THE TIMEOUT!

Some news about this feature for MX keys mini?

Can we get a response from Logitech on this?

Around two years you reviewing this feature..

I lost about 2 hours trying to configuring this thing and also writing this comment. Logitech just kill productivity. Thank you and congratz Logitech, you are very successfull in disturbing your customers.

hey logi maybe you will already fix that and add the settings for backlight?

As a long time Logitech customer I have now moved onto another brand of wireless keyboard that allows for the backlight to be kept on. I would have gladly put up with less battery life on the MX keys as the light constantly turning off on me has driven me insane. I often pause for longer than 30 seconds and while the proximity sensor is okay sometimes, most of the time I have to wave my hand above the keyboard for some seconds before the backlight kicks in and then I have to reset myself and of course moments later when I next pause I have to do the same thing over. What I can't understand is why this is not user definable through the Options software. The sad thing for Logitech is that they already had me as a loyal customer to their ecosystem (over 10 active Logitech devices currently) for years but now I have begun looking at alternatives. I'm sure you'll fix the problem with a miniscule firmware change once the feedback gets critical but, it's just sad that you'll only fix this once it hurts your bottom line rather than proactively listening to loyal customers.

This feedback page is a lie.

People have apparently been begging for this for years but if the market research says that 9 intelligent users will complain about the absense of a basic function, and 10 idiots will complain about the battery draining too fast because they forget to turn the backlight off . . . well, there's your answer.

Logitech will never, ever fix this problem because they have a fundamental lack of respect for their loyal customers. This is purely a numbers game to them without a single concern for business ethics.