Macbook A1706. 820-00239-A doesn't see SSD questionmark folder

[PITERPENY]

Hi all. help with diagnosing Macbook A1706. 820-00239-A. doesn't see SSD. question mark folder. runs from an external drive. All power supplies are normal except for the SSD power supply.

PICCOLO_IUVD=1.834v.
PP3V3_S5_SSD=3.352v
PP3V3_2V7_NAND_VCC=0v.
PP1V8_SSD_COLD=0v.
PP1V2_SSD_COLD=0v.
PPBUS_G3H_R=13.08v.
PPDCIN_G3H_CHGR_R=19.90c.
PPVIN_G3H_P3V3G3H=19.65v.
SSD_BOOT_LB_L 1.8V
SSD_PWR_EN_LB_L 0V
STORAGE_LB_EN 3.33V
SSD_RESET_LB_L 3.32V
SSD_PCIE_CLKREO_LB_L 3.32V
LPSR_EN_LB_L 3.32
replaced U9300 everything remained unchanged. please help me out

[reformatt]

Re: Macbook A1706. 820-00239-A doesn't see SSD questionmark folder

PP3V3_2V7_NAND_VCC=0v

PP5V_S4_P2V7NAND_LB=?
PICCOLO_VEN1=?

[PITERPENY]

Re: Macbook A1706. 820-00239-A doesn't see SSD questionmark folder

pp3v3_2v7_nand_vcc=0v

pp5v_s4_p2v7nand_lb=?
Piccolo_ven1=?

pp5v_s4_p2v7nand_lb=5.12v
piccolo_ven1=0v

[reformatt]

Re: Macbook A1706. 820-00239-A doesn't see SSD questionmark folder

Check SSD_DBG_UART_R2D/SSD_DBG_UART_R2D_R for activity, pullups etc. These lines come from U2060 and appear on the JTAG header as well so check both of these too.

[PITERPENY]

Re: Macbook A1706. 820-00239-A doesn't see SSD questionmark folder

check ssd_dbg_uart_r2d/ssd_dbg_uart_r2d_r for activity, pullups etc. These lines come from u2060 and appear on the jtag header as well so check both of these too.

ssd_dbg_uart_r2d=3.3v
ssd_dbg_uart_r2d_r=3.3v
pp1v8_s0=1.8v
debuguart_sel_soc=1.79v
pch_ssd_soc_uart_d2r=3.3v
pch_ssd_soc_uart_r2d=3.3v

[reformatt]

Re: Macbook A1706. 820-00239-A doesn't see SSD questionmark folder

debuguart_sel_soc=1.79v

Needs to be low for PCH data to route to M+/M-. Coming from the CPU. It could well be that these signals are active during boot, and as SSD not detected it reverts to debug state. I would be checking these signals during initial power on.

[PITERPENY]

Re: Macbook A1706. 820-00239-A doesn't see SSD questionmark folder

debuguart_sel_soc=1.79v

Needs to be low for PCH data to route to M+/M-. Coming from the CPU. It could well be that these signals are active during boot, and as SSD not detected it reverts to debug state. I would be checking these signals during initial power on.

compared debuguart_sel_soc
on the working board there is also the indicator debuguart_sel_soc=1.79v.
at startup the readings do not change debuguart_sel_soc=1.79v
( . the diagram also indicates debuguart_sel_soc=1.8v

[piernov]

Re: Macbook A1706. 820-00239-A doesn't see SSD questionmark folder

Checked Lifeboat dongle presence and connector state?

[PITERPENY]

Re: Macbook A1706. 820-00239-A doesn't see SSD questionmark folder

Checked Lifeboat dongle presence and connector state?

LIFEBOAT SSD Side
PPVIN_2V7NAND_LB=13V
PP5V_S4_P2V7NAND_LB=5V
SSD_BOOT_LB_L=1.8V
SSD_PWR_EN_LB_L=0V
STORAGE_LB_EN=3.3V
SSD_RESET_LB_L=3.3V
SSD_PCIE_CLKREQ_LB_L=3.3V
PCIE_SSD_D2R_LB_P<0>=0V
PCIE_SSD_D2R_LB_N<0>=0V
PCIE_SSD_R2D_LB_C_P<0>=0.9V
PCIE_SSD_R2D_LB_C_N<0>=0.9V
PCIE_CLK100M_SSD_LB_P=0V
PCIE_CLK100M_SSD_LB_N=0V
LPSR_EN_LB_L3.3V
PP3V3_S5_SSD_LB=3.35V

[PITERPENY]

Re: Macbook A1706. 820-00239-A doesn't see SSD questionmark folder

Are there really no masters here who understand at least something about this?

[mon2]

Re: Macbook A1706. 820-00239-A doesn't see SSD questionmark folder

I think you have received excellent advice from the best of the best already.

Do review this video if not done already:

https://youtu.be/yt0f3sGSZas?si=C5BqifVFAdVsZZIs

Note that the _L suffix net names are active LOW. So active only if that signal is logic LOW.

The pcie clock is not running so the ssd is not being detected.

What is the history of this logic board? Any liquid damage?

[PITERPENY]

Re: Macbook A1706. 820-00239-A doesn't see SSD questionmark folder

The motherboard looked pristine and new. no damage from moisture or physical. came in for repair after trying to reinstall the OS. I just stopped seeing the ssd. I watched the video on the link a long time ago, but nothing helped because the voltage is normal at PICCOLO_IUVD=1.8V. At the same time, there are no voltages in the area of the SSDs themselves.

[PITERPENY]

Re: Macbook A1706. 820-00239-A doesn't see SSD questionmark folder

After replacing U9011, all voltages on the SSD returned to normal and all SSDs are powered and the system works, but there is still no SSD in the disk utility. Any ideas on what else to try and replace?

[PITERPENY]

Re: Macbook A1706. 820-00239-A doesn't see SSD questionmark folder

I think you have received excellent advice from the best of the best already.

Do review this video if not done already:

https://youtu.be/yt0f3sGSZas?si=C5BqifVFAdVsZZIs

Note that the _L suffix net names are active LOW. So active only if that signal is logic LOW.

The pcie clock is not running so the ssd is not being detected.

What is the history of this logic board? Any liquid damage?

could you please tell me how to check the clock? Everything is fine in the clock terminal.

[PITERPENY]

Re: Macbook A1706. 820-00239-A doesn't see SSD questionmark folder

I also remind you that the system works from an external drive. and if the time is incorrect, the external ssd will not work either.

[PITERPENY]

Re: Macbook A1706. 820-00239-A doesn't see SSD questionmark folder

detected unusual behavior of the SSD_PCIE_CLKREQ_LB_L line 3.3V power appears on it for just a moment and then it becomes 0.088V. Does anyone have any ideas what's wrong?

[mon2]

Re: Macbook A1706. 820-00239-A doesn't see SSD questionmark folder

This is a netname with a '_L' suffix so it is an active LOW signal.

When this line is LOW, the signal is active and enabling the SSD_CLK.

With the J9600 (LIFEBOAT) jumper hat closed, confirm the continuity (diode mode is good to use here) from the PCH to the SSD side. No power during these tests.

That is, you are confirming that the LIFEBOAT jumper block is performing the shorting across the pins.

Also,

PCIE_CLK100M_SSD_LB_P
PCIE_CLK100M_SSD_LB_N

are PCI Express clock signals that are to be driven by the bus master. These pins must be oscillating @ 100 Mhz (differential signals with a positive / negative phase) to allow for the PCIe slave (SSD) to communicate.

Your PC motherboard has the same set of signals on each PCIe expansion slot. The host motherboard creates this PCI Express clock to drive the target PCIe device (ie. could be a video card, USB host controller - addon, serial ports = our market . This is not related to the clock function of the motherboard which is often linked to the RTC (real time clock) label and is usually a slower 32k768 frequency for the clock / calendar chip.

Regardless of the above details, these lines must toggle else the SSD cannot communicate. Do check these same signals on the PCH side for activity:

PCIE_CLK100M_SSD_P
PCIE_CLK100M_SSD_N

[PITERPENY]

Re: Macbook A1706. 820-00239-A doesn't see SSD questionmark folder

This is a netname with a '_L' suffix so it is an active LOW signal.

When this line is LOW, the signal is active and enabling the SSD_CLK.

With the J9600 (LIFEBOAT) jumper hat closed, confirm the continuity (diode mode is good to use here) from the PCH to the SSD side. No power during these tests.

That is, you are confirming that the LIFEBOAT jumper block is performing the shorting across the pins.

Also,

PCIE_CLK100M_SSD_LB_P
PCIE_CLK100M_SSD_LB_N

are PCI Express clock signals that are to be driven by the bus master. These pins must be oscillating @ 100 Mhz (differential signals with a positive / negative phase) to allow for the PCIe slave (SSD) to communicate.

Your PC motherboard has the same set of signals on each PCIe expansion slot. The host motherboard creates this PCI Express clock to drive the target PCIe device (ie. could be a video card, USB host controller - addon, serial ports = our market . This is not related to the clock function of the motherboard which is often linked to the RTC (real time clock) label and is usually a slower 32k768 frequency for the clock / calendar chip.

Regardless of the above details, these lines must toggle else the SSD cannot communicate. Do check these same signals on the PCH side for activity:

PCIE_CLK100M_SSD_P
PCIE_CLK100M_SSD_N

thanks for the extensive answer).
checked with a LIFEBOAT multimeter (in diode mode)) everything is flawless.
PCIE_CLK100M_SSD_N=0.436v
PCIE_CLK100M_SSD_LB_N=0.426V
PCIE_CLK100M_SSD_P=0.436v
PCIE_CLK100M_SSD_N=0.426V
SSD_CLKREQ_L_R when switched on 3.34V and then 0.096V
It seems that the voltages of the SSD chips themselves are normal. how do you think ? Tell me what else to watch, otherwise I haven't been able to solve this problem for five days now(:да:

[mon2]

Re: Macbook A1706. 820-00239-A doesn't see SSD questionmark folder

Sorry, should have been more clear. Meter in diode mode.

One meter probe on pin # 1 on the lifeboat connector; other meter probe on pin # 2. Should tone beep if pins #1 and #2 are shorted.

Repeat for each horizontal pair of pins to confirm the lifeboard short block is doing its job. Perhaps an overkill task but worth a review.

[PITERPENY]

Re: Macbook A1706. 820-00239-A doesn't see SSD questionmark folder

Sorry, should have been more clear. Meter in diode mode.

One meter probe on pin # 1 on the lifeboat connector; other meter probe on pin # 2. Should tone beep if pins #1 and #2 are shorted.

Repeat for each horizontal pair of pins to confirm the lifeboard short block is doing its job. Perhaps an overkill task but worth a review.

I temporarily removed it and soldered it directly.