820-3115 short

Kyle93

Active member
Arrived powering on with chime but no backlght. Liquid damaged. Replaced everything affected by the spill. Turned on with backlight for a few seconds but then turned off stuck at 0.268 amps. PPBUS_G3H now 1.5V and shorted 0.001 diode mode.

Injected voltage into PPBUS_G3H but nothing is getting hot.

What to check next??
 

2informaticos

Administrator
Staff member
You've just fried the CPU.
After lot of times mentioned how to NOT inject voltage there :(.

Post exact ohm values on PPBUS_G3H and all big coils.
I suspect an high-side MOSFET shorted on CPU power supply; worst scenario.
 

Kyle93

Active member
Replaced Q7550 Q7510 and Q7520 at the same time which solved that issue and it now turns on.

New problem now is fast fan spin and running slow. Ran full ASD EFI and surprisingly it passed. Replaced Q75660 and all values are good on R5665 R5660 and R5661.

What to check next???
 

2informaticos

Administrator
Staff member
Install HWMonitor and check sor any strange temp value.
Test disconnecting camera and also try known good trackpad board/flex.
 

Kyle93

Active member
This is what I get on HW monitor but not sure how to reference it to the board.
 

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2informaticos

Administrator
Staff member
Strange to have temp errors on both SMC SMBus 1 and 2 at same time.
Did you try known good trackpad board and cable?

Be sure R5260/61 and R5270/71 are good.
Inspect U5511 area for corrosion.
Check its traces to Q5510/15/20.
Post diode mode on its SCL/SDA lines.
 

Kyle93

Active member
yes known good trackpad and cable are being used.

R5260 4.7k R5261 4.7k

U5511 area perfect condition with no corrosion.

Traces to Q5510/15/20 are good

diode SCL .507 SDA .507
 
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