820-4929-a No usb activity all rails present

TBFix

Member
I have a A1508 16gb board number 802-4924-a here with no USB/Cpu activity.
No sign of spillage on the board.
It drawing 370ma with fan spin . Not sure if its normal for these board to reboot twice?.
All power rails are present.
SYS_PWROK_R = 3.42v
CPUVR_PGOOD_R = 3.3v
PM_S0_PGOOD = 3.42v
SMC_DELAYED_PWRGD = 3.42v
PM_S0_PGOOD = 3.42v
PP3V42_G3H = 3.42v
PPVCC_S0_CPU =1.8v

I have tried a known good clean dump from here.
Is there a list of order of signals ? , like some PC schematics have the signal order.

Any input appreciated.
 

2informaticos

Administrator
Staff member
Looks like CPU issue.
Be sure all SPI Bus Series Termination aresistors are good, as their traces too.
Also try to clean/remove J6100.

Check for knocked off components, especially near the CPU heatsink holes.
 

TBFix

Member
Thanks for your input again. There was no connection between R6118 and R6130, ran a jumper wire and usb activity kicked in and posted.
 
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