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820-3476 PPbuS_G3H, S5_PWRGD, Fan Spin present
- Thread starter grmacs
- Start date
Really strange, the fan is powered from 5V_S0, derived from 5V_S4...
"PM_BATLOW _L= 0V"
Original 60/85W Magsafe 2 charger?
Check if board starts with both charger and battery connected.
Original 60/85W Magsafe 2 charger?
Check if board starts with both charger and battery connected.
Do not confuse between boot and start.
A board can start (turns on), but doesn't boot (not working really).
You don't get any pulse on big coils?
Trigger SMC_ONOFF_L and check for drop pulse at PM_PWRBTN_L.
PM_SLP_SUS_L and 3V3_SUS present?
Check all RTC signals.
A board can start (turns on), but doesn't boot (not working really).
You don't get any pulse on big coils?
Trigger SMC_ONOFF_L and check for drop pulse at PM_PWRBTN_L.
PM_SLP_SUS_L and 3V3_SUS present?
Check all RTC signals.
"no drop pulse on pm_pwrbtn_L when triggering smc_ONOFF_L"
This points to SMC issue.
But keep in mind, PCH can still block the SMC to make its job correctly.
Changing SMC is the next step.
However, check first signals and voltages for U5000 (2 OF 2) at page 36.
Just in case, try to start in SMC bypass also.
This points to SMC issue.
But keep in mind, PCH can still block the SMC to make its job correctly.
Changing SMC is the next step.
However, check first signals and voltages for U5000 (2 OF 2) at page 36.
Just in case, try to start in SMC bypass also.
This board magically started up while I was poking around and now consistently starts. I reflowed the SMC regardless and gave it a love tap. No boot. I couldn't get my EZP2019 to flash a new bios to the chip so I swapped bios from different board and it now boots but running high fans so guessing may need cleanME which I'm not sure I'm going to be able to do. The chip appears to be a Micron 25Q064 which isn't an option and none of the "close" options are working either.
Did you try to solder back original BIOS chip and test again?