Macbook Pro - 820-00875-A - No G3H

[nrcslim89]

Hello all, please i need help.
I have here a Macbook Pro with 820-00875-A logic board.

Recently this board don't turn on at all.
I try to search for 12V. but that value is not present anywhere.
I check fuses and they are fine.
I saw some videos butwithout any clue...
I don't know what i have wrong or don't check well but could some one help me please ?

[piernov]

Re: Macbook Pro - 820-00875-A - No G3H

Check voltage and current consumption on USB-C ammeter.

[nrcslim89]

Re: Macbook Pro - 820-00875-A - No G3H

Check voltage and current consumption on USB-C ammeter.

Sorry i don't have one... but 19V should be present at C3101 and i only have 5V

After that something seems bad... because i dont have the right values at COILS...

[piernov]

Re: Macbook Pro - 820-00875-A - No G3H

USB-C ammeter really helps narrowing down the problem…
But if you only have 5V you can start from there.

Using a genuine Apple Magsafe USB-C 61W//87W?
Liquid damage?
5V on both ports?
PP3V3_G3H present?
CD3215 heating up?


This may help as well. http://logiwiki.shinycomputers.com/i...ootup_Sequence

[nrcslim89]

Re: Macbook Pro - 820-00875-A - No G3H

USB-C ammeter really helps narrowing down the problem…
But if you only have 5V you can start from there.

Using a genuine Apple Magsafe USB-C 61W//87W?
Liquid damage?
5V on both ports?
PP3V3_G3H present?
CD3215 heating up?


This may help as well. http://logiwiki.shinycomputers.com/i...ootup_Sequence

Im working with original magsafe USB-C
I don't have 5V on all circuit, is ONLY present in C3201 near U3200 IC.
On C3101 near U3100 i think i should have between 5V to 20V... but i don't have nothing... and theres no short or hot points visible.
I already put alcohol isoprop on board... and nothing disappear.
I think theres a problem on Power Rail... but... what or where ??

On coils i dont have voltage... and on PPBUS_G3H (F7000) i have 0.660V.

[mferna14]

Re: Macbook Pro - 820-00875-A - No G3H

Hi all I have excatly this same problem.. I am not at all getting the 20 Volts. Kindly inform me when I look at the logiwiki step trouble shooting they say that PP20V_USBC_XB_VBUS_F should be 5v where as the Schematics says that this is a 20V line rail & it coming from J3300, so confusing... I am only getting 5v out here. What is the right voltage out here please????

[mon2]

Re: Macbook Pro - 820-00875-A - No G3H

Please review:

https://logi.wiki/index.php/CD3215_Bootup_Sequence

The order of voltage rails is shown in the circles.

So +5v0 comes in from the external power adapter which offers power delivery feature (PD). This means that if both parties (the adapter & the logic board) chat and negotiate the power contracts using the CC1 / CC2 lines, then the logic board can ask the external adapter to dial up "20V" for its use.

A common show stopper is that if one or more of the CD3215 USB PD controllers is not working properly then this issue can prevent the target 20V from being enabled.

Start with the above landing page to review.

Do you have access to the schematic and boardview diagrams for your unit?

[mferna14]

Re: Macbook Pro - 820-00875-A - No G3H

Mon2, thank you so much for your answer.. it was great ... First thing what I did was replaced both the CD3215 as I thought too that one of these chip were defective. I took it out from a 100% known good water damaged logic board. This board was atleast turning on & giving the 20V when I plugged in the adapter, only it had a lot of liquid spill on the it, this is why I started to repair the other one. So I know both are working chip. Yes I have the schematics & the boardview. Now I will again go through the bootup Seq'. If any other tips, I will really appreciate. Thanks

[macrepair]

Re: Macbook Pro - 820-00875-A - No G3H

Mon2, thank you so much for your answer.. it was great ... First thing what I did was replaced both the CD3215 as I thought too that one of these chip were defective. I took it out from a 100% known good water damaged logic board. This board was atleast turning on & giving the 20V when I plugged in the adapter, only it had a lot of liquid spill on the it, this is why I started to repair the other one. So I know both are working chip. Yes I have the schematics & the boardview. Now I will again go through the bootup Seq'. If any other tips, I will really appreciate. Thanks

Hi Friend,

Have you already repaired the MacBook?