No Backlight AMD Framework 13

Community Support
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Hi Brains Trust, I used my brain first, I promise.

I have an AMD Framework 13 from batch 3 (if that matters) I recently had a drink bottle open inside my backpack and my Framework got wet, I did the normal open it up, clean with isopropyl alcohol, leave for a few days before powering on routine.

On powering on the fingerprint sensor lit up but at the time that seemed to be all, thankfully my Bluetooth earbuds connected at the same time signalling there was more to this case, upon further inspection it seems it’s just the backlight that is dead, everything else seems to be working, I can faintly see the screen if I hold a torch up and the laptop works without issue when connected to a dock and monitors.

I received a new screen by mail and installed it and no luck, same issue again. I’m now turning to you all to see if you could provide any other ideas to what I can be.

Thanks in advance.

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If a backlight does not work, it is down to two things:

  1. faulty display
  2. faulty mainboard that supplies the power to the backlight.

As you have already replaced the display, it can only mean a fault with the mainboard. Probably one of the power rails shorted and damaged a component.

Options:

  1. Order new mainboard
  2. go to a repair shop and ask them to fix it.

If you plug an external display in, and the laptop is working fine in all other respects apart from the backlight, the mainboard might be cheap to fix at a repair shop.

1 Like
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It could also mean the brightness setting via the keyboard has turned the brightness off. Would be worth trying that first before playing with the main board. My suspicion would be that some liquid got around the brightness key on the keyboard and (may still be) turned the brightness way down.

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Windows is showing brightness at maximum. As much as I wanted this to be the solution, it looks like it might be a Mainboard issue.

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It is a shame we don’t have a full FW schematic.
One only needs to trace the 17.6V back from the EDP port until you find the component that has failed and replace it.
One would trace it back from the eDP connector. Find it does not have the 17.6V.
Then back to the UV7-G516A1, and then on back to the RV918 until you see the 17.6V again.
Although saying that, quite a lot of the eDP 17.6V INVPWR schematic is there, so if you have a multi-meter or a scope you could probably trace it back.
Also, looking at the schematic, I have a question and parts that might be linked to the backlight not working:

  1. Is sound working as it should?
  2. Is the TPM working as it should?

Also, tracing back the “BKL_PWM_LCD” and “BKOFF#_R” from the eDP connector back to the APU.