thinkpad e15 nm-c421

[badcapjerboard]

mon2 Thank you for your very helpful posts. Could you point me in the right direction? I have a thinkpad e15 nm-c421 that i got with a loose jack that couldn't get a charging light in any position.
After replacing the jack, i get 5v to the board, but no amps at least on my cheap tester and the light goes out after first lighting up(on the tester,but plug light stays on). I have no shorts to ground or between pins on the jack itself, but the diode mode red on ground does seem off on a couple pins based on what was posted above. Pins 10 and 11 rx2n and rx2p have no reading, OL, but they do have continuity to the board at r6312/13.
LDO pin has 3.3v on U6301 and U5901, but the i2c pins nothing and cc2 is 1.4v and cc1 nothing.

[mon2]

The OL readings from the USB type C connector may be due to the dc blocking caps that are in series on this line. Continue to trace the connection by inspecting and testing the series EMI filter @ FL6304. Then the caps @ C6314 / C6315. Check if you see OL on the side of the cap that faces the PD controller. This side should be ok and not OL.

On this note, if the CCx pins are mating with the PD controller + PD controller is not damaged + PD controller has firmware that has not been corrupted, then the PD controller should be able to communicate over this 1 wire BMC interface to extract out the list of PD contracts available from the power adapter (current & voltage pairs). Then the PD controller will select the optimum PD contract to power the board which is often 20V.

If the USB type C meter is blanking out then there is some shorted part onboard would be my first guess. Would you have a thermal camera? Someone may send off a heat signature and will be a glow in the camera. Once the heat is too much, there is a cutoff on the power rail and then the cycle repeats.

Confirm the CCx pins in diode mode (no power when testing in diode mode). If you see something not suitable in diode mode, then inspect and remove the ESD parts on that rail which may be shorted from a hit from an ESD event.

In summary, 5v is the default power up voltage from the power adapter. No current draw means just that, no load of any value so the power path is not proceeding to the charger IC (most likely). Regardless, the PD controller is the one who selects the PD contract so focus on that region first. From the specs, this laptop is all about USB Type C which is sad because some models offered both - type C and the old school power connector to power the board.

[badcapjerboard]

Thank you for your help. The two resistors in fl6304 read 1.5ohm same as others nearby so seems ok. The side of caps 6314/15 towards the controller read .7 in diode mode with red on ground. Both cc pins at the connector read .6 in diode mode.
Funny i tried the thermal camera a different time and didn't see much, but now i do see the controller lighting up. Not much only about 25c but stands out. Same with d12503. That diode reads .6 in one direction and ol the other.
would you assue it's bad anyhow and replace the controller u5901 and the diode?

[badcapjerboard]

I guess they made this a new thread. so my chips came from ali and i replaced u5901 and d12503. I'm unclear what the next step is. Should i try it as is or is there no point since i put a blank pd controller?
Is the only way to proceed to get the laptop on by somehow charging a battery and flashing a bios update from command line? mon2

[badcapjerboard]

Update. After replacing the pd controller a second time the board is now drawing some amps unlike before and nothing glows in the thermal camera, but it is only running at 5v.
I have usb connector manager error UCM-UCSI ACPI Device. Code 43 and trying a cmos reset didn't help as well as uninstalling the device as the error comes back after a minute.
Is it possible the bios update is not programming the pd controller? Not sure how to get past this. mon2