On looking over this logic board in a little more detail, I've noticed that Q3100, a dual mosfet FDPC4044 is missing and must have removed by the tech who worked on the board.

I don't want to waste the time of those on this forum and am first going to see if I can get hold of this chap to find out exactly what work he did, so that I can try to get the board back to at least having all the components it needs. I noticed an inductor missing as well, but am not sure whether he removed it, or if the board was fabricated without it.

I feel it's best to pause this thread...

PP3V3_UPC_XB_LDO is 3.24V for U3100, 0.37V for UB300, 0.26V for UB400, 0V for U3200.

PP3V3_G3H is 0 or close to it on all four cd3215s. From watching too many Louis Rossmann vids, this is a bad thing...

Still working my way through the inductors - there are many and some are tiny.

Unfortunately I need to leave this until the weekend - I'll post L values then. Thanks for your help!!

Hello! I'm trying to resuscitate a Macbook that the local tech gave up on. I have the board view and schematic and have the main board out of the case.

Of the 4 usb-c ports, 3 cycle at 5V - they all go up to about 1.5A, then seem to switch off, back to 5V 0A, up to 1.5A, and off again. The cycle lasts a few seconds - maybe 3s.

The 4th port doesn't cycle and draws ~0.5A at 5V consistently. It seems it's the port linked to U3100 - it's on that side of the board and is the port closest to the battery and the CD3215C00 chips.

I've read that the CD3215s are...

Hi all, I'm a mech / software engineer determined to fix things where most would give up, even if it means dabbling and tinkering with electronics where my knowledge is somewhat limited. I've had moderate success with electronics repairs in the past. I'm tucked away on the southernmost tip of Africa.