820-00165 No power on pm_slp_s5_l, no pulse

[Hermann Neupert]

Hi, board came with some minor water damage, mostly in U7090 and U5110 areas, caps and resistors look fine, no shorts. Since I didn´t find anytingh unusual I put the board in the ultrasonic cleaner. Board don´t turn on, no fan, only light in the charger.

SMC_ONOFF_L = 3.38V
P3V3_S5 =3.32V
PM_PWRBTN_L = 3.40V
U6100 legs 1,2,3,5,6,7,8 = 3.32V
SMC_Reset_L = 3.37V

PM_SLP_S5_L = 0V, no pulse

Any ideas?

 

[2informaticos]

Do you get 3V3_SUS?

Trigger SMC_ONOFF_L and check for drop pulse at PM_PWRBTN_L (at same time).

 

[Hermann Neupert]

pp3v3_sus = 3.32V

PM_PWRBTN_L goes down when SMC_ONOFF_L is triggered. Pulses betwen 0.6V and 1.73V, but I think is because is what me multimeter gets to read in such short time.

 

[2informaticos]

OK, check for pulse at PM_SLP_S4_L at same moment.

 

[Hermann Neupert]

PM_SLP_S4_L is always = 0V, no pulses when power is conected or if SMC_OnOff is trigger.
PM_SLP_5_L is the same always 0V in multimeter.

PM_SLP_S4_L in diode mode shows a value of 456.

 

[2informaticos]

Seems to have a PCH related problem.
Need to check if gets all the correct signals.
Check PM_DSW_PWRGD, SMC_ADAPTER_EN, PCH_DSWVRMEN, PM_BATLOW_L, PM_RSMRST_L and the 4 PCH's RTC signals.

 

[Hermann Neupert]

PM_DSW_PWRGD = 3.40V
SMC_ADAPTER_EN = 3.40V
PCH_DSWVRMEN= 3.21V
PM_BATLOW_L= 0.03V
PM_RSMRST_L = 3.26V
PCH_INTRUDER_L = 3.00V
PCH_INTVRMEN = 3.16V
PCH_SRTCRST_L = 3.31V
RTC_RESET_L = 3.31-V

R1410 is good = 10Kohms

PM_BATLOW_L goes to 0V if I disconnect power, and right to 0.03V when I plug the power again, it stays at 0.03V when SMC_ONOFF_L is trigger. In diode mode PM_BATLOW_L is 681.

 

[2informaticos]

Test with original 45/60W Magsafe 2 charger.

 

[Hermann Neupert]

Is a 60W original charger, but the cord was replaced, works with others boards, but that was my problem. Thanks