Macbook 82-03437 SMC

[Instafixx]

Device came in with no power on. Baord was clean. PPBUS was at 8.16V.
SMC was already recalled once by someone. Went ahead and replaced the SMC.
Symptoms are same but the device turns on now. PPBUS at 8.16V and no MagSafe light. So Weird.

KP/TP also won't work. Power Button Works. Replaced the cable as well.

 

[2informaticos]

Check diode mode to ground and voltage at SCL/SDA lines of battery bus.
Be sure R7100 is good.
Also check the lid signal and power rails at trackpad connector.

 

[Instafixx]

SCL/SDA line on battery bus are ok. Both diode and voltage.
R7100 Resistance across pins .4 Ohms.
TP Connector Diode Mode Readings:

SMC_LSOC_RST_L is 1.4
TPAD_WAKE_L is 0.002

 

[2informaticos]

I meant voltage level for trackpad connector.

 

[Instafixx]

TPAD_WAKE short now removed.
Still the same.
I get 3.3V on the SMC lines.

How is the device turning on with PPBUS at 8.17V

 

[2informaticos]

Machine can turn on with 8.17V, but PPBUS_G3H is not properly controlled.
Check SMC_BC_ACOK level and SYS_ONEWIRE continuity between MLB and LIO boards.

 

[Instafixx]

SMC_BC_ACOK is 0.537 in diode mode and resistance across R5187 is 100kOhms.
SYS_ONEWIRE Diode is .760

 

[2informaticos]

When we talk about "level", I meant voltage level...

 

[Instafixx]

SMC_BC_ACOK is 3.3V.
THE SMC is of 820-00165 and I intend to flash it but the keypad isn't working hence I cannot boot via my USB

 

[2informaticos]

00165 SMC should allow you enter macOS.
Could you access SSD's macOS?

Trackpad works different before and after macOS loading.
If you can't use keyboard for boot menu, may have problems with trackpad itself, or its USB connection to PCH.
BTW, did you try Right ALT key for boot menu?
Also test with USB keyboard/mouse.