Keyboard backlight not working

Question

Lenovo ThinkPad T14 Gen 5

Service and repair resources for the fifth generation of Lenovo's popular 14-inch business laptop. First available in April 2024.

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I have recently updated the RAM from 16 to 32 GBytes. After the upgrade the keyboard backlight is not working anymore. No light is present.

My supposition is that either an IC/MOSFET is gone or a trace is broken.

Is there any way to determine if:

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I was quite lucky and the Lenovo warranty was honored also in my current location.

The shop changed the entire motherboard but they told me that some trace that delivered the current to the keyboard backlight was interrupted.

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Sean @smmicroserve crwdns2934065:0crwdne2934065:0: 1 · Answer 1 · 2025-07-24T10:02:21-07:00

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Check the ribbon cable for debris or damage on the keyboard, do the same for the connector on the systemboard.

Drivers? I know this not a Dell lol...but drivers may have a part in it.

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