820-01700 no power

[2informaticos]

For some reason, CD3215 chips do not allow input voltage to arrive at R7020.
Check voltage and diode mode at LDO rails of all CD3215 chips.

 

[Kyle93]

PP1V5_UPC_TA_LDO_CORE 1.5V

PP1V5_UPC_TB_LDO_CORE 0V .489


PP1V5_UPC_XA_LDO_CORE 0V .493

PP1V5_UPC_XB_LDO_CORE 0V .493

 

[2informaticos]

Each chip has 3 more LDO rails.

When you check for voltage, connect charger to corresponding port.
Also test it in the both connection ways.

 

[Kyle93]

UB300

PP1V5_UPC_TA_LDO_CORE 1.5V
PP3V3_UPC_TA_LDO 3.4V

UB400

PP1V5_UPC_TB_LDO_CORE 1.5V .491
PP3V3_UPC_TB_LDO 3.4V .490

U3100

PP3V3_UPC_XA_LDO 3.4V .382
PP1V5_UPC_TA_LDO_CORE 1.5V .490

U3200

PP3V3_UPC_XB_LDO 3.4V
PP1V5_UPC_TB_LDO_CORE 1.5V

I do not see any further LDO lines that go into the chips. Can you specify what other rails need to be measured???

 

[Kyle93]

R7020 is 5v now

PPBUS_G3H still only 1v

 

[Kyle93]

solved after replacing u7000

 

[Kyle93]

This recently came back for warranty and has the strangest issue. It will be stuck at 5v 0 amps but if measuring C7021 with the multi meter it will boot normally at 20v. As soon as the red probe is removed from C7021 it goes back to 5V 0 amps.

Any ideas how to fix this?

 

[2informaticos]

Check the real values of R7021/22.
Resolder any components related with CSIP/N lines of U7000.

You can also try removing C7021/22.