820-00244 no water damage, 0V on the charger

[MaxFix]

Hi,
1. 0V on the charger
2. replaced U3100, now 5V on the charger. U3100 replaced with the same model B01 but from another donor board that had 20V on charger.
3. All big coils 0V. PPBUS_G3H - 0V. P3V3G3H - 0V.
4. Checked for short on all the big coils. L7210, L7230, L7410, L7430 seem to be shorted. shows 16 in diode mode and gives a constant beep.
Please advice how to proceed.

 

[2informaticos]

CPU coils could have low values anormal.
Someone else can confirm if has similar board.

Do you get 3V0_AON and PP2V9_SYSCLK?
Post basic voltages for U7000.

 

[MaxFix]

3V0_AON - 3V
PP2V9_SYSCLK - 0V

could you please be more specific about voltages for U7000?

 

[MaxFix]

Any solution?

 

[2informaticos]

Check P_IN, ACIN, ACOK, A/BMON, VDDA, VDDP_1/2, VCC_VR1.
Use surrounding components to measure, if no test points available.

 

[MaxFix]

P_IN - 0V
ACIN - 0V
ACOK - 0.07V
CHGR_BMON - 0V
CHGR_AMON - 0V
CHGR_LDO_VDDA - 4.98V
CHGR_LDO_VDDP - 4.98V

VCC_VR1 can not find this value

 

[2informaticos]

"P_IN - 0V"
Really sure?
How do you get CHGR_LDO_P5V0 then???
Please, post accurate information.

 

[MaxFix]

CHGR_LDO_P5V0 is confirmed.
P_in witch one? I don't find just that line. are those capacitor near the CPU?

 

[2informaticos]

I was giving you U7000 connections (internal chip names); just find corresponding board lines.

 

[MaxFix]

U7000 lines
CHGR_ACIN - 1.08V
SMC_BC_ACOK - 0V
CHGR_AMOR - 0V
CHGR_BMOR - 0V
CHGR_LDO_VDDA - 4.8V
CHGR_LDO_VDDP - 2.62V

 

[2informaticos]

Looks like bad U7000.
Be aware, this one has firmware!

 

[MaxFix]

Do you have solution for fix it?

 

[2informaticos]

It is probably waste of time; all A1534s end with dead CPU anyway.

You can only try if find ISL95530 from same model board.