820-00928 NO water damage, 20V, No fan, no chime, no image, no boot

[Mori3000]

Hello

I have a A1707 with board 820-00928 That not starting at all, it is not liquid damaged and have no physical problem.

I read some of the posts and didi some checked up some parts. I found out that PM_BATLOW_L is 0v but could not find out where the problem is.

Appreciate your help

 

[piernov]

Using a genuine Apple 87W USB-C AC adapter?
What's the voltage and current consumption shown on USB-C ammeter?
All G3H and S5 rails have correct voltage?

 

[2informaticos]

Do you get 3V3_S5/SUS?
Post exact voltage for PPBUS_G3H and 3V3_G3H.

 

[Mori3000]

PPBUS_G3H 12.6 v
PP3V3_G3H 3.4 v
PP3V3_S5 3.3 v
PP3V3_S5_POLARIS 3.3 v
PP3V3_SUS 3.3 v

On the USB-C meter i have:
19.7 v
0.02 A
5mah

 

[2informaticos]

PM_BATLOW_L must be high, if not PCH doesn't start power on sequence.
Try original 87W charger.

Did you try to start with both charger and battery connected?
Does it charge the battery?

 

[Mori3000]

I using an original 87W charger and tried to connect both batteri and charger , but no boot.

I,m not sure what do you mean by if not PCH doesn't start power on sequence.

where the PM_BATLOW_L start från, i could not really find out what component turn it on.

 

[2informaticos]

Post SMC_ONOFF_L, PM_PWRBTN_L and PM_RSMRST_L.
Trigger SMC_ONOFF_L and check for drop pulse at PM_PWRBTN_L at same time.

 

[Mori3000]

SMC_ONOFF_L 3.4v
PM_PWRBTN_L 3.3v
PM_RSMRST_L 3.3v

What voltage should i trigger 3.4v?

 

[Mori3000]

I triggered 5 v but got 0 v on PM_PWRBTN_L

 

[2informaticos]

"What voltage should i trigger 3.4v?"
???
"Trigger SMC_ONOFF_L..."

You can use R5226, or SW5200 pads, instead of power button.
Make only temporary contact.