Question HP DV2000 Dim after few seconds

Jul 6, 2020
Good Day,

I've had a strange problem which I hope the world of internet can help me out with. I have a laptop that is dimming the screen so it can't be seen (except with a light). The screen is usually normal for a few seconds when first turned on, then suddenly dulls. It goes through the normal booting as if nothing is wrong. The screen can be seen using an external monitor no worries when loading into windows. The laptop lcd is the same dullness, while the external monitor is bright and normal. Trying different screen shortcuts to change between the 2 does not help the laptops LCD at all.

Booting to BIOS, or USB Linux is the same result. So it just seems to be the backlight that is the issue. If I turn the laptop off, sometimes when I restart it the screen is dull straight away, otherwise, it takes just a few seconds. It varies between 2-10 seconds I would say randomly.

Now I went straight to replacing the LCD inverter as the usual cause. Got the exact same part, however same result. Checked all the cables that connect between inverters, motherboard and the LCD. All seem to be fine to me. Also checked on the sleep switch but seems to have been disabled already as does nothing.

Also usual steps of replacing ram, hard drive, hard resets, different power supply.

Any of you have an idea where I should be looking next? Thanks :)