820-3476-A - not power on

nameless

Member
Hey everybody

I've got A1502 EMC 2678 Macbook pro which doesn't power on. I'm getting amber light when plugged in but no fan spin.

HISTORY : customer dropped on flat surface.

I tested with two different screens still nothing : no chime, no backlight, no fan spin.

Here some measurements :

PPBUS_G3H - 12.6v
PP3V42_G3H 3.4v
PP5V_S5 - 5v
PP3V3_S5 - 3.3v
PP3v42_G3H - 3.4v
PP3V3_SUS - 3.3V
PM_RSMRST_L - 3.3v
SMC_ONOFF_L - 3.3v
PM_PWRBTN_L - 1.2v
PM_BATLOW_L - 0v

Was getting 2.1v on pin 3 U7100, after replace it's 3.6v with no changes

Also PPVIN_S0_1V05S0_LDO is 0V
and C7649 - 0V

If I understood schematics correctly, its created by PCH

is it dead ?

Thank you for you support

Regards
 

2informaticos

Administrator
Staff member
"PM_BATLOW_L - 0v"
PCH requires high level to start power on sequence.
Are you using original 60/85W Magsafe 2 charger?

Is the battery charging?
Try to turn on the board with both charger and battery connected.

Check R1405.
If good, then low level on PM_PWRBTN_L may be caused by broken solder/trace under PCH.
 
Top