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History? PP3v3_G3H is basically the VDD main rail which powers the PMU. The PMU powers the T2, which talks to the CD3217 USB C controllers. What do you ask yourself if you find a missing voltage? Is it shorted! Find out, and get back to us.

PCH, CPU, a bad RAM chip or a missing RAM power rail could be possible differentials. Post voltages on PP1v35_S3_MEM, PP0v75_S3_MEM_VREFDQ.

This was a bad idea. Never inject into a cpu/t2 rail. This could be a short on any of the SLP/AWAKE rails. An open circuit on any of the inductors near the PMU can also cause this behavior. See more troubleshooting info for this problem on https://repair.wiki/w/A2179_2020_MacBook_Air ---...

The fan not spinning is normal. It doesn't spin the fan until the CPU is 85-90C. Are you saying you no backlight then the device shuts off? Please clarify.

The M1s likely need to be signed into the OS to give you image on external. You may need to have the internal display plugged in on the 820-02016 or else it will be stuck in the SLEEP 3 state. If caps lock light comes on the machine is booted. Are you positive this is not no backlight? It can...

OK, As I suspected. We had a totally different issue, Now we have a secondary issue. What version OS is the machine you are using to restore using? Did you note any amperage before putting it in DFU? Why was U7000 changed? What was missing? Was anything measured or was it just empirically...

This isn't an M1 board. This is Intel. Also you aren't pulling 10 amps. Post voltage on L7210.

Here is normal diode and resistance measurements from a known good board I recorded and posted on repair.wiki. Keep in mind silicon resistance changes with heat. The board must be cold at room temp to get accurate readings. Was the board hot by chance when you measured this? Anything above 100*C...

Not a short. What is resistance to ground on this line? _________________________________ 1.38 amps is too high. Is the battery connected? If so disconnect it. Does the amperage remain high?

If you get an Apple logo with a progress bar, the NANDs and T2 are basically working. This is very suspect for an issue within the enclosure. Inspect trackpad and keyboard connector area for signs of damage. Or better yet, try in a known working enclosure. I suspect you have something totally...

This is typical of a current sensing issue. Resistance between pins 17/18 and 27/28 of the ISL6259? Measure between the pins, not to ground.

PMU_ONOFF_L should not be 12.6v!!!!!! You are measuring wrong, or you have a very bad problem somewhere.

OK. First off, you need to use a OEM 85W MagSafe 2. If you use a lower wattage or shitty knockoff, PM_BATLOW_L will be held low and the board will not start. Look on the power aliases page of the schematic. You need all "Always Present" G3H or G3 Hot rails before S5 rails. You need all S5...

1. The rails on these machines usually cycle when there is a short somewhere. Post Resistance to GND values on PP3v3_G3H, PP3v3_G3H_RTC and PPBUS_G3H. 2. Do you have steady 5v on PPDCIN_G3H?

They should be cross compatible, however the 2017 uses a slightly faster GPU and slightly faster CPU.

54 volts means there is no load on the circuit. Your issue is likely a bad screen. These models are common for flexgate. Have you tried a known good screen yet?

I wouldn't waste time with this. These boards (00875 and 00840) are awful. Almost every one I see in my shop has a shorted CPU or does not post from a dead CPU.

Same symptoms before GPU replacement?

That is a possibility, I will check with people and see if it is a netflix and safari issue alone. I have heard of this same issue on both 1466 and 1932, so I just wanted to see if maybe, both machines were running the same MacOs version #.

I have seen several of these machines that exhibit graphical glitches (typically green) while playing full screen video. The machine will otherwise behave normally with no other issues. I suspect this is either one of 2 things. A. Driver issue related to a specific MacOs version OR. B...