820-00923 NAND missing

Maltinho

New member
Hey,

820-00923 A1706 with missing SSD. PP3V3_S5_SSD is 0,785V. Just wanted to measure around Piccolo Current Sense and - everything's missing. Just to be sure, there should be U5920, R5920, R5925, C5920? Also looks like U5910 is missing...

Do i have bad schematics or is this real?

IMG_0280.jpg
 

2informaticos

Administrator
Staff member
If you have direct connection over R5920 (copper trace), then this circuitry area is not populated.

Be sure J9600 metal plate is in place and check left/right connections.
 

Maltinho

New member
Installed J9600 metal plate. PPVIN_2V7NAND_LB is 13.01V instead of 2.7

edit: looks like PPVIN_2V7NAND_LB should be 13V?

Found R9415 P2V7NAND_DRVL_R and P2V7NAND_DRVL at 0V
.461 Diode
PP2V7_NAND_VCC is 5.107V instead of 2.7, same for PP2V7_NAND_PVCC
 
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2informaticos

Administrator
Staff member
Why do you make wrong assumptions so easy?
Do not confuse a power rail with associated signals.

Do you get voltage at L9300/20/30/40 and L9400?
 

Maltinho

New member
L9300 0.9V
L9320 0.85V
L9330 1.22V
L9340 1.81V
L9400 2.67V

From schematics PP2V7_NAND_VCC should be 2.7V
 

2informaticos

Administrator
Staff member
Do you think to have big difference between 2.67 and 2.7???

As SSD power rails are good, check if is recognized in Disk Utility.
You can use Target Disk mode, or USB installer.
 

Maltinho

New member
I tried to install OS X before i opened the Thread. I just tried it again with USB Installer and there's no SSD recognized. Questionmark Folder also still coming up.

IMG_0282.jpg
 

2informaticos

Administrator
Staff member
"about PP2V7_NAND_PVCC measured 5.107V and schematics say it must be 2.7"
PLEASE, try to understand schematics, BEFORE making such WRONG assumption!!!

Be sure to select "Show All Devices" option in Disk Utility.
If still not detected, then read above:
"check left/right connections."
 

Maltinho

New member
Which left/right connections? Of J9600?

Checked continuity for J9600, its okay. Tried a J9600 from another A1707, SSD still not present.
 
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2informaticos

Administrator
Staff member
Check SSD basic signals; SSD_BOOT_LB_L, SSD_PWR_EN_LB_L, STORAGE_LB_EN, SSD_RESET_LB_L, SSD_PCIE_CLKREO_LB_L, LPSR_EN_LB_L.
If possible check 100MHz SSD clock with o-scope, or frequency meter.
 

Maltinho

New member
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

Where to check clock? PCIE_CLK100M_SSD_LB_N or PCIE_CLK100M_SSD_LB_P?

at R9420 P2V7NAND_EN and PICCOLO_VEN1 are 3.35V - is that correct?
 
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2informaticos

Administrator
Staff member
Values look good.
Not sure about CLKREQ level, can you compare with working board?

" Where to check clock?"
Any CLK100M line...
 
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