Macbook 820-01700 Stuck at 5V

[powerblackout]

Re: Macbook 820-01700 Stuck at 5V

ah ok that's a neat idea.

So remove the resistors R9098, R9598, bridge the two points together for each resistor, then find a 3v3 source and tie it in with each line to force the regulator on?

Maybe tie it to
PP3V3_G3H_SSD0_SNS - 3.38v
PP3V3_G3H_SSD1_SNS - 3.38v
?

[mon2]

Re: Macbook 820-01700 Stuck at 5V

I believe you noted in this thread that only one of the SSD devices is stuffed ?

So I would just consider to test perhaps SSD0 if that is what is linked to your SSD that is onboard / module based. No point in hard wiring the other SSD logic if there is nothing onboard.

Yes, remove the series resistor so that we are not having 2 different driver levels bashing their heads together. Once the series resistor is removed, ok to use the 3v3 rail you have noted onto this ENABLE pin. This is a safe logic / voltage value for this TI device.

[powerblackout]

Re: Macbook 820-01700 Stuck at 5V

Sorry if I misspoke before:

SSD0 has 2 NANDs, SSD1 has 1 NAND. I will need both in order to get DFU to succeed, or does T2 only store partitions on SSD0?

I got the 2.5V working, do you think the PP0v9_SSD0 and PP1v8_SSD0 lines for the SSD are also required to make it work? those are still 0.0v

[mon2]

Re: Macbook 820-01700 Stuck at 5V

Yes, see your point. Correct that each of these rails are required to power up the SSD. This is now getting sticky.

The balance of the missing rails are created by U9500.

Again, the question stands as to why these rails are not being enabled.

Post the voltage readings for:

I2C_SSD0_SCL
I2C_SSD0_SDA

[powerblackout]

Re: Macbook 820-01700 Stuck at 5V

I2C_SSD0_SCL - 1.8v
I2C_SSD0_SDA - 1.8v

I hooked an oscilloscope up to those lines. Right when I plug the power in I see a bit of communication, not sure if any of the traffic is directed at the U9000/U9500 though

[bluestone]

Re: Macbook 820-01700 Stuck at 5V

Sorry if I misspoke before:

SSD0 has 2 NANDs, SSD1 has 1 NAND. I will need both in order to get DFU to succeed, or does T2 only store partitions on SSD0?

I got the 2.5V working, do you think the PP0v9_SSD0 and PP1v8_SSD0 lines for the SSD are also required to make it work? those are still 0.0v

You need to get 2.5v on both SSD1 and SSD0, and yes you need PP1v8 and PP0V9

[powerblackout]

Re: Macbook 820-01700 Stuck at 5V

You need to get 2.5v on both SSD1 and SSD0, and yes you need PP1v8 and PP0V9

Do you think getting the 1.8 and 0.9 working will also get ocarina working? Is that required also?

[powerblackout]

Re: Macbook 820-01700 Stuck at 5V

Thinking about ocarina last night, U9000 has a FORCE_EN that connects to SSD1_OCARINA_FORCE_EN tied to R9011 resistor that attaches to ground. Since SSD1_OCARINA_FORCE_EN doesn't end in a _L that means raising it above 0v would trigger it? If I remove that resistor and attach it to a 1v1 or 3v3 line maybe that will turn it on?

EDIT: Actually, looking through this power sequence https://cdn.badcaps-static.com/pdfs/...4429db3748.pdf
I am missing P5VG3S_EN, since that is higher up on the power sequence should I try and fix that first? It comes straight from the CALPE-PMU

EDIT 2: I found this thread where they are also missing P5VG3S_EN https://www.badcaps.net/forum/showthread.php?t=93596
I too am trying to use a USB-A to USB-C coming from a mac mini, perhaps I need to find a macbook with usb-c and try again.

[powerblackout]

Re: Macbook 820-01700 Stuck at 5V

Adding to this evidence, if I plug all 4 usb connectors from the Mac mini to the MacBook about 1 out of 5 times doing the revive I'm able to get the MacBook to go from 12.3v to 12.7v. once in there I can get the MacBook into dfu mode using the keyboard shortcut keys. Maybe plugging it into another MacBook gives it more power to use than a mac mini can provide.

[powerblackout]

Re: Macbook 820-01700 Stuck at 5V

Well that's idea is no longer valid, tried it with a macbook, got the voltage up to 12.7, still no P5VG3S_EN. Recovery still fails. Giving back to customer, can't figure it out

[nikey22]

Re: Macbook 820-01700 Stuck at 5V

PPBUS_G3H should be 12.63V
If PPBUS_G3H is 12.32V, T2 chip is stuck in DFU mode.
What is your exact PPBUS_G3H reading (to two decimal places please)
As usual, @mon2 is spot on, alluding to this pattern in post #9.

There is actually no reason to activate the SSD lines at this time because in DFU mode, the data from the host computer is communicated directly into the T2-rom chip (IBridgeOS updates etc..) and doesn't need the use of the NAND at the moment.
Looks like you already tested R5220 (PP1V8_SLPS2R - 1.86v) This is the SMC I2C data lines. They seem good.

We must determine why the T2 chip is remaining in this state.

I need a boardview/.pdf to examine the other culprits like ISL (U7000) and PMU (U7800) in further detail

[powerblackout]

Re: Macbook 820-01700 Stuck at 5V

PPBUS_G3H would start at 12.32, then if I plugged in 3 other usb cords from the mac mini to the macbook i could get it to go to 12.63 1 out of 5 times when trying the revive process. If I only use the one restore cable it would never leave 12.32v and the revive process would fail after a minute. Once in the 12.63V state I could see i2c traffic happening every second with the battery, and the reviving would hang for 12 or so minutes then eventually fail with the error code saying it couldn't find ssd.