Morning all, I have a head scratcher if anyone can help. I have a Lenovo thinkpad 14 gen 4 (schematic attached). Plug charger in and it negotiates 20v but the USB C controller (UT2) Wont't drop pin 1 & pin 40 low to enable 20v to pass through UT5 to BQ (PU1). I've replaced all three chips with no change. However, I decided to test with a lenovo charger plug which I had lying around, this has a USB A socket so I used a A-C Cable, now this stays at 5v but pins 1 and 40 drop low and 5v flows to the BQ and actually charges the battery cycling 350ma to 1.2a draw on the charger. I have manually charged the battery and the laptop switches on fine. I can't find a data sheet for the PD and at this point I'm honestly stumped. Any pointers would be great.
https://www.badcaps.net/forum/troubl...e501-schematic
https://www.badcaps.net/forum/troubl...e501-schematic
