820-2914-a not turning on.

BCN_Techs

Member
Update. I repassed ISL and changed it again. Now not fluctuating sometimes. Sometimes it is going up and down. PPBUS is ok. Still no green light on charger.
 

BCN_Techs

Member
Again GPU?:D this week is GPU deatch week. Any way to check it and be sure that GPU is dead?

PDCIN is low anyway. It must be about 18 and it is 17V.
 

2informaticos

Administrator
Staff member
"It must be about 18 and it is 17V."
WOW, such a "BIIIG" difference!!!
Do you really think is that relevant???

"PPBUS is ok."
12.2V, or 12.6V?

Post U6900/01 voltages.
Did you try another DCIN board?

What about SMC_RESET_L, SMC_ADAPTER_EN, PM_BATLOW_L, 3V3_S5, 3V3_SUS?
Are you using 85W charger?
 

BCN_Techs

Member
PPBUS 12.2V, is that means SMC is not working?

U6900

Pin 1 ,4,5 3.4V

U6901

Pins 1,2, 3.3 V
Pin 3 0V
Pin 4,5 3,4 V


SMC_RESET_L - 3.4V
SMC_ADAPTER_EN - 0V
PM_BATLOW_L - 0V
PP3V3_S5 - is present
3V3_SUS - 0V


The charger is 85W and already tried know working dc in.
 

2informaticos

Administrator
Staff member
So PPBUS_G3H is not OK at all.
Do NOT assume things like this in the future.

"PM_BATLOW_L - 0V"
Also no good.
Post SMC_BATLOW_L and PM_SLP_SUS_L too.

Check continuity from U6900 to DCIN central pin (Magsafe connector).
 

BCN_Techs

Member
It was bad SMC, changed it now it boots, light is ok PPBUS is 12,6 but after apple load stack on white screen. GPU is dead. heat it up and doesnt work. So disabled dedicated GPU and now mac us rinning ok with secondary graphic card.
 
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