A1534 820-00244 no power

[hgoncalves]

Hi,

I have an A1534 820-00244 with no power.

I have 20V on ampmeter, but 0A.

No big coil seams to be shorted.

PP3V3_G3H = 3.289V

PP5V_S5 = 5V
PP5V_S0 = 0V

PP3V3R3V0_AON = 3.298V

PP3V3_S5 = 0V and 0.388 on diode reading.
PP3V3_SUS = 0V and 0.398 on diode reading

Can you help?

 

[2informaticos]

What is exact PPBUS_G3H voltage, w/ and w/o battery connected?

Did you test in SMC bypass mode?

 

[hgoncalves]

PPBUS_G3H has 8.69V with, and without battery connected.

SMC bypass has the same result (no power on)

 

[2informaticos]

Any fault history available?

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

 

[hgoncalves]

Client said it stoped working over night.

PM_PWRBTN_L has 0V and no drop pulse when triggering SMC_ONOFF_L.

 

[2informaticos]

Pufff, it should stay high normally.
SMC_ONOFF_L stays at 3V?

 

[hgoncalves]

Hi.

Yes. SMC_ONOFF_L has steady 3.297V

 

[2informaticos]

Be sure R1570 is good.
Check diode mode to ground at PM_PWRBTN_L.
Possibly bad PCH/CPU...

 

[hgoncalves]

Hi.

R1570 has 0.994 ohm (prety close to 1k I think), and PM_PWRBTN_L has 2k resistance to ground.

Shall I replace R1570?

 

[2informaticos]

"R1570 has 0.994 ohm"
You've meant Kohm, I suppose...

"PM_PWRBTN_L has 2k resistance to ground"
Compare with good board; use diode mode instead.

 

[hgoncalves]

Sorry... I meant 0.994 kohm.

PM_PWRBTN_L has 0.730 in diode reading (same on another board)

 

[2informaticos]

SMC controls this signal.
But PCH can block it...