Laptop ACER A315-51-52TW po zalaniu nie uruchamia się

it is correct since pin 1, 2 are in parallel with PR3 of 0.01 ohm.

W takim razie gdzie szukać przyczyny źle pracującego PU1 bądź złego napięcia na n 1-3 PQ1?

Check the solder joints on all pins of charger chip PU1, especially on pins 1 and 28.

All pin of PU1 are correct solder.
Between pin 19 and 20 of PU1 is short circut. It's correct?

terabajt ha scritto:Between pin 19 and 20 of PU1 is short circut. It's correct?

Yes, it is correct. The low resistance between this pins is caused by "shunt" resistor PR209.

Measure the voltages to ground on pins 3, 18, 19, 25 of charger chip PU1 with connected charger only (without battery).

PU1
pin 3: 0.82V
pin 18: 3.7V
pin 19: 1.23 V
pin 25: 0.38V

Measure the resistance to ground on coil PL5.
Measure the resistance to ground on pin 25 of PU1.

If both resistances are high (in kΩ range or greater) the PU1 is bad.

After replace PU1:
PL5 : 9.2 MOhm and falling down
PIN 25 of PU1 : 5.29MOhm

PU1:
pin 3: 3.6 V to 3.9 V
pin 18: 3.8 V to 4.0 V
pin 19: 3.8 V to 4.0 V
pin 25: 5.75 V

Voltage on pin 25 of PU1 seems ok now.

Check the transistor PQ2.

PQ2 is ok, I chnge it for a new one.
PQ2
n1: 3.8V - 4.0V and 6.0 MOhm and falling down
n4: 3.8V - 4.0V and 17 MOhm and falling down
n5: 3.4 - 4.0V and 133 KOhm



Shouldn't be here PC17?

Measure the voltages on pin 4 of PU1.
Verify that PQ1 is functional.

terabajt ha scritto:Shouldn't be here PC17?

PC17 is factory not soldered.

The voltages on pin 4 of PU1 is jumping: 3.4V to 4.1 V and 2.76 MOhm to the ground

Bridge the pins 1 and 8 of transistor PQ1. Set the laboratory power supply to 19V, limit the current to 0,2A and connect it to the DC jack of the board.
What is the current consumption of the board in this case?

After that consumption of the board is 0A and on pin 1 is 19V, pin4 is 24V, pin5 19V.
How can i set the PS-305D limit to 0.2 A?

terabajt ha scritto:How can i set the PS-305D limit to 0.2 A?

You should make a short circuit on the output (bridge + and - output terminals with a wire). In this case the power supply should jump to the constant current mode (C.C. led should light up) and in this case you have possibility to set the current to 0,2A with a "Fine" and "Coarse" Current potentiometers.

terabajt ha scritto:After that consumption of the board is 0A

Are you sure? There is usually a current consumption a few mA (for example 10mA = 0,01A).

Are you sure? There is usually a current consumption a few mA (for example 10mA = 0,01A).

Yes, my WEP show's 0.00A (and after set AMPS to LO : 000 mA
.... but:
after bridge the pins 1 and 8 of transistor PQ1 and remove bridge, on PL3 i have 3.4V and on PL2 i have 5.2 V until power off with power supply

edit
I measured the power consumption with my UNIT and it show 0.006 A

Measure the resistances between listed pins of transistor PQ1:
a) Between pin 1 and pin 4
b) Between pin 1 and pin 8
c) Between pin 4 and pin 8

Also measure the resistance between both pins of diode PD1.

On PQ1:
a) Between pin 1 and pin 4: OL
b) Between pin 1 and pin 8 : 2.2 MOhm
c) Between pin 4 and pin 8: 9.8 MOhm

PD1: both pin 3-1 :0.63 KOhm

Do you replaced the charger chip PU1 with exactly the same as it was the original one (including "S" extension)?