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Yes, it is pulsing for a second but after that it is back to 0 V. I only have a CRT so i took a photo with my phone as good as i could. Hope that is good enought...

Ok... Thank you for the help

yes... 3.38 V at R5185

ok, thanks. So as the "temporary short" is ok and not the problem here i kept searching and - what else could it be - the 5V_S3 enable and PM_SLP_S4_L are missing... Are there areas on this board (like U1900 on the 820-3437) that i could check?

yes it is at pin 8 of the Bios chip 3.34 V

This 820-2523 sometimes turns on but mostly it is dead. Sometimes it turns on but has a black screen. Except for a lot of smokey black dust the board looks fine. I checked power rails and PP5_S3 is missing. After i disconnected the charger it is shortet (0.02V in diode mode) but it is slowly...

I am not sure if i did the right thing but i measured the resistances on all these rails. I attached a document where i compared it to a working 820-3462 (as that is the closest equivalent working board i have) and i also added the components where i took the measurements. I hope that hepls but...

I contacted the customer today and he said, that he left the macbook copying some files to an external drove and as he came back it was dead... I checked all rails listed in the scematic and they are all not shorted as far as i can tell. Few of them have a readings of 0.13 V in diode mode to GND...

PP1V35_S3_CPUDDR : ~255 Ohm (multimeter counting up and down -+10 Ohm) PPVCC_S0_CPU : <70 Ohm (multimeter slowly counting down)

PP3V3_S5 is 3.341 V and PPBUS_G3H is 12.61 V. The only thing the customer said is that it just stopped working... And the whole machine looks near perfekt (inside and outside...)

I wanted to say, that PPVRTC is also straight and not pulsing. But it is present - straight 3,3 V. Sorry, my english is not the best. LCD cable and connector look fine and i get 0,38 V to GND in diode mode at pin 28, 29 and 30 (with the LCD cable plugged in).

PP5V_S4 is straight 0V - even if i put the scope to 0.1 us/div. Same thing for PPVRTC_G3H. There was indeed a short on PP5V_S4. I slowly injected voltage in there (starting at 0.9 V - 3.5 V were enough to feel something getting hot) and U8300 got hot. I replced it. The short is gone now (0.377 V...

Hello, this 820-3476 is not turning on. It has an orange light in the charger and there is no visible damage on the board. PP5V_S4 is not there because PM_SLP_S4_L is also missing. I checked U1900 and i ge a 1V p-p clock signal on pin 12 (on my oszilloskop) so i think this is fine. U1950 is...

I think this one is done - unfortunately. Memory Voltagte is not shortet but VCORE is (thats why all the other signals are missing) and it had to be present bevore so i think the CPU died during the process... This was not my first time reflowing ram and i experience the same with this boards...

Actually it is dead now. I preheated the board first and did not shield CPU/PCH as they were on the other side of the board. So i thought that i dont need to shield them... I did not directly run over them with hot air as they are not unter the ram.

Hello, this 820-3032 had 3x beeping ram. I gave all 16 Ram ICs a reflow and now it wont turn on. PP5V_S0 is there on the fan connector but the fan won´t spin. That is confusing to me. PP0V75_S0_DDRVTT is 0V so the ram is not powered. I followed this path and came to PLT_RESET_L and...

Thank you. I try to get it to post and get back to you it it turns on. In the mean time i try tp understand the BIOS some more. Today i have no idea how this works, what the ME region is and how it can be fixed/reprogrammed...

Thank you very much for the great explanation. I took U7940 and R7918 off the board and still only 500 Ohms to GND. So i try to reflow U1800 (i have nothing to lose in a case like this - maybe there was water under it) and i also ordered two new chips so i can try to swap U1800 completely... I...

PP3V3_S5, PP5V_S5 and PPVRTC_G3H are present. There was a lot of corrosion on the by the LVDS, T29 circuit, around the SMC and a little bit around Q5300. Same on the other side of the board but there it was only on some small components between U1800 L3895 and C7523)

This 820-2936-B was waterdamaged. It has a green light but wont turn on. I replaced all bad looking components and cleaned the board. I cheched power rails and PP5V_SUS is missing because the enable is missing too. This enable is created by U7940 and PM_SLP_SUS_L. R7918 is only 0.5K Ohm ( but i...