820-2915-A no power, no green light

[lucas502]

Hello!

I have this mac that does not turn on, does not turn on any led on the magsafe and no fan. (I already rewrite bios)
No corrosion/liquid damage

measurements:
PPBUS_G3H = 12.59v
PP3V42_G3H = 3.485v
PP5V_S0 = 0.013v
PP3V3_S5 = 3.355v
PP3V3_SUS = 0v
PP1V05_SUS = 0v
PP3V3_S0 = 0v
PPVCC_S0_CPU = 0v

When trigger SMC_ONOFF_L, nothing happens.

Thanks!

 

[2informaticos]

Put back original BIOS; is not related with Magsafe light.
SPI chip usually requires 3V3_SUS; why touch it, if is not even powered?

Post MLB code (maybe 820-2936/3115), not DCIN.
Then we can give you more information.

 

[lucas502]

Edited: 820-2915-A (Sorry..)

Rewrited original bios

What can i check now?

 

[2informaticos]

In this board, U6100 is powered by 3V3_S5 indeed; however, not related with missing Magsafe light.

Check PM_DSW_PWRGD, PCH_DSWRMEN and the 4 (four) PCH's RTC signals.

 

[lucas502]

PM_DSW_PWRGD = 3.48v
PCH_DSWVRMEN = 3.226v

RTC_RESET_L = 3.347v
PCH_SRTCRST_L = 3.347v
PCH_INTRUDER_L = 3.062v
PCH_INTVRMEN_L = 3.256v

PP5V_S5 = 5v
SMC_PM_G2_EN = 3.482v

apparently everything is ok, what else can I check?

Thanks

 

[2informaticos]

Chek SMC_ADAPTER_EN and PM_BATLOW_L.
Be sure to use 85W original charger.

 

[lucas502]

I only have 60w original charger, its a problem?

SMC_ADAPTER_EN - 3.40v
PM_BATLOW_L - 0v

PS: with lab PSU, the green light sometimes turns on and stays on, sometimes turns on and off in a few seconds (without pattern).
With original supply, rarely turns on the green light, but when it lights up stays on for 7 seconds and off.

however, now I plugged in the original charger (60w) and the green light stays on ever .. !? (but never turned on)

 

[2informaticos]

60W charger is not original for this machine!
This board will not start with other charger alone, than 85W.
Unelss charged battery is plugged in.

 

[Askaleto]

Lucas, please have a look at this video. If you don't have much time, I suggest to start watching from 5:10.