820-3115 green light,

[Alan.L]

not liquid damage, no corrosion. there is green light. fan doesn't spin. light doesn't change to orange when i connect to a battery.

pp_bus_g3h= 12.59
sys_onewire = 3.431
pp3v42 = 3.45v
pp3v3_sus = 0
pp3v3_s5 = 0
SMC_BC_ACOK = 3.4v
PPVRTC_G3H = 3.53v
PP5V_S5 = 0
PP5V_S3 = 0
smc_reset_L = 3.42v
SMC_PM_G2_EN = 1v
PM_SLP_SUS_L = 0v
SMC_ADAPTER_EN = 0v
PM_BATLOW_L = 0

u7200 pin 16 is 12.59v
no 32khz clock signal because missing pp3v3_s5.
0.510 ohms in diode mode on PP5V_S5



PPBUS is present at Q7220 but PP3v3_s5 is 0v
bad u7200? - the only pin has voltage it is pin 16.
could be bad SMC. 0v on SMC_BATLOW_L when i connect battery and magsafe.

 

[JohnB8812]

Is PP3v42 3.4 of 4.4? If 4.4, that’s too high and could be causing issues. If 3.4, resistance between pins 17/18 and 27/28 of the ISL6259?

 

[Alan.L]

ops sorry 3.45v on pp3v42.


pins 17/18 and 27/28 = 3.2 ohms and 20 ohms

 

[2informaticos]

Post U7941 voltages.

 

[Alan.L]

u7941

pin1 - 3.45
pin2 - 1v
pin3 - 0v
pin4 - 3.4v
pin5 - GND
pin6 - 0v
pin7 - 0v
pin8 - 0v

 

[Alan.L]

i found Pin2 of u7841 in diode mode is 0.059

dead smc

 

[2informaticos]

What is U2841???

"pin2 - 1v"
SMC_PM_G2_EN is too low.
Is there where you have .059 in diode mode?
If yes, remove U7941 and check again.
If still low, put quality flux and reflow SMC.
Low value again, means you must change SMC...

 

[Alan.L]

yes U7941. sry

 

[Alan.L]

i've removed u7941 its still low, then i removed smc its still low. board has a internal short?


should i inject 3v to SMC_PM_G2_EN, see where get hot?

 

[2informaticos]

SMC_PM_G2_EN is shared only between SMC and U7941.
There is no other component connected.
059 diode mode value means 100 ohms maybe (or more), so I bet you cannot heat anything injecting voltage.

Depending where is the trace pulled down to ground, sometime is possible to isolate that point and bypass it.

 

[Alan.L]

Yeah i know. I guess i better not to inject voltage and risk of burning another trace. I’ll have to run a long jumper underneath the SMC.

 

[Alan.L]

going to use the original smc, checked SMC_PM_G2_EN on the chip is 0.700