ACER NITRO AN515-41-F8JT mb C5V08 LA-E903P - nie uruchamia się

Witam. NA stole ACER NITRO AN515-41-F8JT mb C5V08 LA-E903P. Notebook trafił ze zwarciem na gnieździe zasilania. Uszkodzony (zwarty) PQ302 - B04N03 tuż obok gniazda dc został zamieniony na MDU1511. Zwarcie zniknęło - niestety laptop bez oznak życia. Pobór z zasilacza serwisowego 0,00V . Napięcie na drenie MDU1511 - 19V, na bramce i źródle 0V.
Na cewce PL302 obok złącza baterii 0,40V - pozostałe cewki 0V
Pobór prądu 0,00v - czasem na ułamek sekundy wzrasta do 0,02. Brak ładowania baterii.
Poproszę o wskazówki w celu zlokalizowania usterki

Hello!

Measure the resistance to ground on any pin of resistor PR304.

If the resistance is high (in kΩ range or greater), measure the voltages to ground on pins 1, 3, 4, 5, 6, 11, 16, 17, 20 of charger chip PU301 with connected power supply only (without battery).

Resistance on PR304 is low (4ohm) . Short-circuit test on PR304 ?

pawel1978 ha scritto:Resistance on PR304 is low (4ohm) . Short-circuit test on PR304 ?

Yes, perform a short circuit test on any pin of resistor PR304. Limit the voltage to 1V.
If you will reach 1V during the test and nothing heats, rise up the voltage limit to 3V. If still nothing, go to 5V.

2,8V, 1,9A - the UAPU1 gets warm

Replace UAPU1.

Machine ha scritto:Replace UAPU1.

Not for now, because the issue is probably somewhere else.

Measure the resistances on all coils in reference to resistor PR304.

PL302 - 165 Kohm
PL1405 - 7 ohm
PL402 - 2,35 Kohm
PL503 - 650 ohm
PL1402 - 40 ohm
PL602 - 1,6 Kohm
PL904 - 27 ohm
PL805 - 1 ohm
PL804 - 1 ohm
PL903- 26 ohm
PL401 - 10 Kohm
PL1002 - 60 ohm
PL1403 - 4,5 ohm
PL1404 - 4,5 ohm
PL803 - 3 ohm

Check the transistors PQ802, PQ803, PQ804. One of them is damaged almost for sure.

This transistors are actually dual transistors in single package:

I don't quite know how to measure them. However, one of them has a short circuit between D1 - S1 / D2.
The designation of these pq is 6962. Only pq802 and pq804 are present.

pawel1978 ha scritto:I don't quite know how to measure them.

Test each transistor as two separated ones.

pawel1978 ha scritto:However, one of them has a short circuit between D1 - S1 / D2.

So this transistor is damaged and needs to be replaced.

According to the diagram, it is AON6992 - on the MB board I have 6962 - no meaning?

pawel1978 ha scritto:on the MB board I have 6962

It is AON6962 and it is the replacement for AON6992.
Use the transistor AON6962, if you don't have it you can also use AON6992.

I replaced the PQ802 and PQ804 with 6992. The notebook started with a black screen - 1.7A consumption, turned off after a few seconds. The second attempt to run the same. At the moment, after pressing the power button, it starts up with a black screen to 0.26A and after 3 seconds. turns off.

Measure the voltages to ground on all coils for a short time, when the machine is turned on. You may have to turn on the machine multiple times, to measure all of the voltages.

With today's approach to the subject, the notebook behaves differently. It starts with a black screen and stands at 1.2A - it does not turn off. Unfortunately, some coils are under the cooling system - an attempt to start without a heat sink ends with an immediate shutdown. Maybe the residual measurements will be enough?

PL302 - 3V
PL401 - 5 V
PL402 - 3,3 V
PL503 - 1 V

PL602 - 1,07 V
PL904 - 0,8V
PL903- ?

PL805 - ?
PL803 - 1 V
PL804 - ?

PL1002 - ?

PL1402 - 0 V
PL1403 - ?
PL1404 - ?
PL1405 - 0 V

pawel1978 ha scritto:PL503 - 1 V

it should be 1,2V. Check this measurement again.

The measurements on the coils under the heatsink are also needed. If these coils are inaccessible, you can solder the wires to this coils for the measurement purpose (make sure that the end of wires does not touch anything on the board).

Yes, PL503 - 1,2V - my fault

PL804 - 0,95V
PL805 - 0,95V

PL1403 - 0 V
PL1404 - 0 V

PL1002 - 0 V

PL903- 0,8V

Try to reflash the BIOS chip. Don't forget to save the old dump.

Measure the power consumption (in mA) of the board when the machine is turned on with old and with new BIOS.

I reprogrammed the bios with the forum batch, the notebook responds to the switch, it still starts up with a black screen, power consumption 1A and stands