My Lenovo X1 fingerprint sensor stopped working. The issue was the cable connecting the sensor to the motherboard. Replacements can be found on Ebay/Aliexpress for around £10.

the FRU of my ribbon cable is: SC10Q25678

I didn’t have to remove the battery. Remember those laptops have intrusion sensors and Lenovo might find out if you opened the lid, invalidating your warranty if you still have one

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