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Finally I flashed the BIOS once again without any change. So I have to stop further investigation due to lag of time and give it a NO-FIX here.

R1720 R7120 are spot on 13,3K But R7123 and R7124 are both 180K instead of 220K... I guess this is OK?

I replaced U7100 with minor changes..... PPVCCSA_S0_CPU came up = 1.1V But PPVCC_S0_CPU =0V And now CPUVR_PGOOD = 0V Now I get 20V / 0.36Aon the amp meter.... How I get the vcore back? Should I expect a dead CPU? Or should I try my luck with flashing the BIOS...

Yes I mean every pin has the right voltage. I double checked it: U7100 CPUVR_PGOOD is indeed UP with 3.45V CPU_VR_EN_R 3.35V The PWM lines have 2.7V None of the SENSE-lines have any voltage....

OK as I said the optical inspection of U7100 and U7210/20/70 is witout any doubts. I checked now all the VIN-pins, VCC-pins, EN-pin and pgood-pin.... All the pins have the voltage they should have. I would like to learn more about the U7100-ic. It seams it is responsible for the vcore-lines and...

The Logicboard have no visible corrosion or burn marks. The whole machine is clean.... I mean CLEAN! No dust in the fins! I'm the first opened it. No shorts on the coils! All the S0-lines comes up except: PPVCC_S0_CPU =0V 4.8Ohms tg PPVCCGT_S0_CPU =0V 2.8Ohms tg PPVCCSA_S0_CPU =0V...

U7000 is responsible for PPBUS_GH3 and charging. I don't think it is faulty because you have PPBUS 8,4V For charging it has to communicate with the SMC and the battery. If it can't communicate there is something wrong with the data lines (Page42) or current sense resistors (Pins 17,18,27,28)...

P3V3S5_EN_R U7201 PIN-21 1,560V should be 3,4V to enable PP3V3_S5 rail!! It comes from U7840 All leads to U7840 and it looks ugly too --> replace

You can say there is no short to ground on the Rail. I missed to say EN PIN12 has to be high to make the whole chip to work. PIN12: P5V3V3_REG_EN comes from SMC_PM_G2_EN! Is this signal present? Can you list up all EN pins? Voltages?

Measure L7260 in diode mode (->+) with RED probe on GND and BLACK probe on L7260 without charger. Put it then in volt mode and measure PIN 23&21 with the charger plugged in.

Check for short on this rail: Diode Mode - red on GND & black on rail. If there is no short look at U7201 TPS51980: - check VIN-Pin23 - check EN-Pin21 what do you measure?

This is one of my two working places

Well this is a good good question. Actually a was lucky since I had no idea which one was bad. I was looking in the web how to identify which chip is bad depending on the address in the log: FAILURE! Data mismatch at local BUFA address 0x00000001394fa4e0, BUFB address 0x000000017e406ce0 BUFA...

I have to add some information here: I've noticed that every single machine with faulty SPI ROM that I had also had a bad RAM Bank! When I think about it it makes sense. The faulty RAM writes back some strange bits and this fucks up the SPI ROM! This will most likely happen if you try to update...

actually aprendiz was asking if you tried to give your GPU a little bit of heat :D apr. ~150-160C If the machine will work after that you know your GPU is dead

Did you checked the VIN-Pin 6 or the resistor R9500?

Do you mean PP1V05_S5_MCP by that?

Yes it is a Mac Air 11" this time but had the same issue with a Mac Air 13" last time

Hi there I've used a lot of ASD images and I always use the EFI-version without any issues. But only on version 3S146 the machine freezes as soon as the USB drive starts. I got the same issue on different machines. I tried both version (EFI and OS) with USB-Drive, USB-DVD drive and USB-HDD. And...

Boot to OSX and set the sound volume to 100% then reboot ...