A1466 board PM_SLP_S5_L = 0v

[DavutAmana]

Good morning all,

I am new to the forum.
I have several 820-00165 board with the same problem :
PM_SLP_S5_L = 0v
SMC work, main power rails work

I accumulated these boards because I was running out of time to working them
What do you recommend to check first?
Thanks in advance

 

[2informaticos]

First of all, welcome to the forum!

ALWAYS check diode mode on all big coils, before apply power to the board.
When you have the board alone on the desk I don't understand why many people don't do that first.
Compare with working board, or your notes taken from other repaurs.
If no short, or low values, then apply power.
Do I consider you already did that, or should I ask you to check now???

You didn't post exact voltage for PPBUS_G3H even; very important information.
Do you have original Magsafe 2 charger?

Post PM_BATLOW_L, SMC_RESET_L, SMC_PM_G2_EN, SMC_ONOFF_L, PM_RSMRST_L, PM_PWRBTN_, PCH_DSWVRMEN and the 4 PCH's RTC signals.

 

[DavutAmana]

Hello my friend,

Yes, thanks for the tip, now I am checking the coils.

In my case everything is ok

PPBUS_G3H = 8.48V
Yes, I am using Apple original magsafe

PM_BATLOW_L 3,31V
SMC_RESET_L 3,39V
SMC_PM_G2_EN 3,42V
SMC_ONOFF_L 3,42V
PM_RSMRST_L 3,25V
PM_PWRBTN_L 3,41V
PCH_DSWVRMEN 2,74V

PCH_INTRUDER_L 2,59V
PCH_INTVRMEN 2,74V
PCH_SRTCRST_L 2,82V
RTC_RESET_L 2,82V

PPVRTC_G3H 2,82V
PP3V3_S5 3,3V
PP3V3_S5RS3RS0_SYSCLKGEN 3,3V
PP1V2_CAM_XTALPCIEVDD 0V
PP3V3_TBTLC 0,5V

I replaced U1900, the measurements remain the same.

Thanks

 

[2informaticos]

Trigger SMC_ONOFF_L and check for drop pulse at PM_PWRBTN_L at same time.
If present, check for pulse at all PM_SLP_Sx_L signals at same time.

Did you try SMC bypass mode?

Tip: use R5115/16 pads, instead of power button.

 

[DavutAmana]

Yes PM_PWRBTN_L there is the fall and go back up right away

PM_SLP_S5_L = 0V
PM_SLP_S4_L = 0V
PM_SLP_S3_L = 0V
PM_SLP_S0_L = 0,052V
PM_SLP_SUS_L = 3,32V

PM_SLP rails have a 3.3V pulsation when I trigger

 

[2informaticos]

Can you clarify please???
You've posted 0V (means steady???), for first 3 PM_SLP signals, then said all pulsing ...

 

[DavutAmana]

PM_SLP_S5_L = 0V (3.3V pulsation when I trigger)
PM_SLP_S4_L = 0V (3.3V pulsation when I trigger)
PM_SLP_S3_L = 0V (3.3V pulsation when I trigger)
PM_SLP_S0_L = 0,052V (3.3V pulsation when I trigger)
PM_SLP_SUS_L = 3,32V

 

[2informaticos]

Then the controlled Sx power rails should pulse too.
For example, PM_SLP_S4_L enables S3 voltages.
PM_SLP_S3_L enables S0 voltages.
Check them all.

"Did you try SMC bypass mode?"
???
"How to" details on the forum...

 

[DavutAmana]

Yes, i have just test and this board work on bypass SMC mode

 

[2informaticos]

Check first AVREF_SMC voltage.
Post exact ohm resistance between pins 17/18 and 27/28 of U7100.
Post CHGR_A/BMON levels.

 

[DavutAmana]

AVREF_SMC = 0V with fast pulse every 2 seconds
pins 27/28 = 21,1 ohm
pins 17/18 = 3,2 ohm
CHGR_AMON 0,029v
CHGR_BMON 0v

 

[2informaticos]

"AVREF_SMC = 0V"
Must be present, even in off state.
Post dioe mode to ground there.
Check the trace for pin 8/U5110.
Also inspect C5021 and C5125 for corrosion.

 

[DavutAmana]

Thank you very much thanks to you I was able to repair 2 cards indeed the problems were linked to U5110 and its continuity.

I believed the presence of PM_BATLOW_L eliminated the SMC problems ...

Thanks for your help