A1398 820-00138 no power

[hgoncalves]

Hi,

I have an A1398 820-00138 with no power:

PPDCIN_G3H = 20V

With board alone on the bench, PPBUS_G3H = 1.098V, and 0.473 on diode reading.

PPVBAT_G3H_CHGR_REG has 0.490 on diode reading.

None big coil seams to be shorted.

No visible damage on the board and no history available.

Can you help?

 

[2informaticos]

Do you get 3V42_G3H at least?
Tried fake charger, or lab PSU?

 

[hgoncalves]

Hi.

3V42_G3H = 1.260V

Using lab PSU

 

[2informaticos]

Diode mode to ground there?
Post U7090 voltages.

 

[hgoncalves]

HI.

The culprit was R7096. It had a high resistande value.

After replacing it, mac started to power on normaly again.

TKS!