820-01987-A short ppbus_g3h

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Hi, this board had liquid damage around U2800 and found a short on PPBUS_G3H that was caused by C9081. Now the board is taking 20v @.08mAmps, can access DFU mode, but get error message when I try to restore it...

 

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That cap is on SSD power supply.
Do you get 2V5_NAND?
You should get all SSD power rails, to complete DFU.

 

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PP2V5_NAND_SSD0 is pulsing... you think the ssd is dead?

 

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Diode mode to ground there?

 

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On L9080 = ,405

 

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Not low value, but there should be stable voltage.
Compare diode mode reading with similar good board.
U9080 may be affected by corrosion; you may need to resolder, or change it.
Check all its surrounding components; pay atention to R9080/81/83.

 

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R9618 wasn´t in place, I put a resistor there and now is not even pulsing, at R9618 I get a pulse of ,086v PMU can be responsible for that?

 

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Check if other R961x resistors marked with "SSD:2L" are in place.
If not, then remove R9618 too.

 

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R9615 and R9617 are not in place
R9616 is in place
R9618 supposed to be there? isn´t this the enable to U9080 ?

 

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As per schematic, your board is in "SSD:4L" configuration.
And enable signal comes directly from U9000.

 

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So I should remove R9618 and check U7800 ? or what can be causing the pulse at PP2V5_NAND_SSD0

 

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Remove R9618, of course.

SSD0_VR_P2V5_EN pulsing too?
L9020/30 get voltage?

 

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PP1V8_SLPS2R is pulsing too but PP3V3_G3H_PMU_VDDMAIN is stable that should create PP1V8_SLPS2R right?

 

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In this case, DFU mode is not possible.
All AWAKE and SLPS2R voltages are required.
To complete it, SSD must get its voltages too.

Check the power sequence using 01055, or 01598 diagrams available on the forum; or logi.wiki webpage.

 

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PPBUS_G3H is at 12,33v but goes a little high when F7000 is in place...
PP3V3_S5 = 0
PP1V8_s5 = 0
PPVPCORE_S5 = 0
PP1V_PRIM = 0
RSMRST_L = 0
SSD0_VR_P2V5_PGOOD = 0

PBUS = 12.3-12.6
PP3V3_G3H_RTC = 3.3
PP3V3_G3H = 3.3

PP1V8_SLPS2R = pulsing
PP1V8_AWAKE = pulsing
PP1V1_SLPS2R = pulsing
PP0V8_SLPS2R = pulsing
PP0V82_SLPDDR = pulsing
PP3V3_AWAKE = pulsing
PPVDDCPUSRAM_AWAKE = pulsing
PP0V9_SLPDDR = pulsing
P1V1_SLPDDR_SOCFET_EN = pulsing
PP1V1_SLPDDR = pulsing
PP1V2_AWAKE = pulsing
PPVDDCPU_AWAKE = pulsing

could it be any of the CD3217 making the voltages pulse?

 

[2informaticos]

Something more affected by corrosion.
Could be a problem with U7800, or adiacent component.
You can try to resolder, or change it.

Compare diode mode to ground readings on all its surrounding coils, with similar good board.