[SOLVED]820-2879-b powering up from battery but no power from charger

[speedyaction]

Hi i have here water damaged 820-2879-b want power up from charger but powering up from battery. water went on Q7030 and Q7035 so i replace it also i replaced u7000 us well this same time.
R7021 : ok
R7022 : ok
R7010 : ok
R7011 : ok
R5281 : 3.4v
R5280 : 3.4v
U7000 pin 14 CHGR_ACOK :3.26v
L7030 0.43v
any help?

 

[aprendiz]

Voltage on pin 2 from U7000??? if it is ok remove F7040 and check if PPBUSG3H comes high....

 

[dukefawks]

Sense resistor/traces issue I bet. Check resistance between pins 17/18 and 27/28 of U7000.

 

[speedyaction]

voltage on pin 2 U7000 16.3v ,
resistance U7000 pin 17/18 : 3.3ohm
resistance U7000 pin 27/28 : 35.68ohm
i also removed F7040 and PPBUSG3H is 0.50 v

 

[dukefawks]

pin 27/28 should be 20 Ohm.

 

[speedyaction]

i know but if i measure resistors they are two 10 ohm

 

[aprendiz]

if it is not the resistor should be the traces....pin 28-R7021-R7020_R7022-pin 27....

 

[speedyaction]

track is no damaged

 

[speedyaction]

sorry i made mistake with measurements resistance U7000 pin 27/28 : 35.68 mega ohm

 

[aprendiz]

If resistors are ok some trace is open, so is up to you.... There is not much more...

 

[speedyaction]

yes resistor are ok so i dont understand why resistance is so high and not sure how to deal with it, never had that kind of problem yet.

 

[larossmann]

At this point, this is nothing more than connect the dots. You must figure out which line is broken.

Also,

resistance U7000 pin 27/28 : 35.68v

Please don't measure resistance in volts, it's hella confusing.

 

[speedyaction]

i was meaning ohm not volts in post above lol i know i done mistake when i read it

 

[speedyaction]

ok fixed. it was broken track between pin 27 U7000 and R7020 pin 3. now laptop working and charging battery . thanks