Acer Spin 5 - Turns on and off after a few seconds

[reformatt]

Re: Acer Spin 5 - Turns on and off after a few seconds

A lot of weird power issues on Acers are usually keyboard related, as power button is integrated. Original fault fits what I’ve seen. Disconnect keyboard and power on by shorting the 2 end pins of the connector with tweezers (usually pin 27/28) to rule it out.

[mon2]

Re: Acer Spin 5 - Turns on and off after a few seconds

Replace the noted mosfet and test again.

[DanFen]

Re: Acer Spin 5 - Turns on and off after a few seconds

Something odd happens when the battery is connected now. The system turns on with high fan spin, but no display still. The battery is also not charging. PU4402 drain starts at 12V and drops to 0.83.

Another thing I noticed while poking the probes around and trying to analyse measurements (voltages), is that there is voltage anywhere I could check other than at PG4707 & PL4801.

PR4802 is 2.49V (I thought this should be 5V?).

[DanFen]

Re: Acer Spin 5 - Turns on and off after a few seconds

Unfortunately I can't find any P-Channel mosfet with that package on any of the boards I have. So that means I'd need to order a replacement.

[DanFen]

Re: Acer Spin 5 - Turns on and off after a few seconds

In this case I'll try to find something similar on some other boards I have around.

[mon2]

Re: Acer Spin 5 - Turns on and off after a few seconds

PU4401

between source (1-2-3) & drain (5-6-7-8): 9.64 (in 20K mode)

Replace PU4401 - this leg is too low for a normal mosfet.

When using the replacement - check the same pins to compare while it is out of the circuit. The same testing should show the 'fresh' mosfet to be a much higher resistance reading than this (defective) one.

Is it normal it keeps on rising? Is the meter charging it the moment I start measuring?

Yes - not a mosfet expert but you can review the numerous articles including this one:

https://www.engineersgarage.com/test...et-part-16-17/

[DanFen]

Re: Acer Spin 5 - Turns on and off after a few seconds

PU4401

between source (1-2-3) & drain (5-6-7-8): 9.64 (in 20K mode)
source (1-2-3) & gate (4): 100 (in 200K mode)
gate (4) & drain (5-6-7-8): ~.975 ( in 2M mode)

PU4402

between source (1-2-3) & drain (5-6-7-8): starts at 75 (in 200K mode) and rises very quickly until out of range
source (1-2-3) & gate (4): starts at 175 (in 200K mode) and rises very quickly until out of range
gate (4) & drain (5-6-7-8): starts at 75 (in 200K mode) and rises very quickly until out of range

Hope I did it correctly. Is it normal it keeps on rising? Is the meter charging it the moment I start measuring?

Remove all power. Meter in resistance mode (start with the lowest scale).

Check the resistance across the mosfet pins @ PU4401.

This is a 8 pin device (4 on each side).

Check the following for resistance:

source (1-2-3) & drain (5-6-7-8)
source (1-2-3) & gate (4)
gate (4) & drain (5-6-7-8)


Post each measurement and the scale on the multimeter used for the test.

Repeat the same tests on the battery mosfet @ PU4402.

If you see '1' or 'OL', then switch to the next higher resistance scale on your meter.

We are checking for a low resistance on the mosfet = defective.

see here for reference (review the resistance chart):
http://electronicsbeliever.com/how-t...0good%20MOSFET.

[mon2]

Re: Acer Spin 5 - Turns on and off after a few seconds

Remove all power. Meter in resistance mode (start with the lowest scale).

Check the resistance across the mosfet pins @ PU4401.

This is a 8 pin device (4 on each side).

Check the following for resistance:

source (1-2-3) & drain (5-6-7-8)
source (1-2-3) & gate (4)
gate (4) & drain (5-6-7-8)


Post each measurement and the scale on the multimeter used for the test.

Repeat the same tests on the battery mosfet @ PU4402.

If you see '1' or 'OL', then switch to the next higher resistance scale on your meter.

We are checking for a low resistance on the mosfet = defective.

see here for reference (review the resistance chart):
http://electronicsbeliever.com/how-t...0good%20MOSFET.

[DanFen]

Re: Acer Spin 5 - Turns on and off after a few seconds

Checked EC8910 for 19V_DCBATOUT and it's 19.49V

REGN on the charger IC is 6V.

This is after it shut down.

.....

Focus on sheet 44 of the schematic = TI Charger IC (PU4403).

3) Check the voltage @ 19V_DCBATOUT - what is the voltage ?

4) After the logic board shuts down, review this 19V_DCBATOUT voltage again. Measurement ?

5) What is the voltage on pin # 24 (PWR_CHG_REGN) of PU4403 charger IC ?

[mon2]

Re: Acer Spin 5 - Turns on and off after a few seconds

Post the voltage readings requested in #2 above.

[DanFen]

Re: Acer Spin 5 - Turns on and off after a few seconds

Yes, the same as that person's And now I have the BV :P (of course)

Review this thread for possible schematic & BV files for your logic board.

Does your logic board look the same as what was just posted ?

https://www.badcaps.net/forum/showth...86#post1147886

LOL - you posted at the same time - is your board the same ?

[mon2]

Re: Acer Spin 5 - Turns on and off after a few seconds

Review this thread for possible schematic & BV files for your logic board.

Does your logic board look the same as what was just posted ?

https://www.badcaps.net/forum/showth...86#post1147886

LOL - you posted at the same time - is your board the same ?

[DanFen]

Re: Acer Spin 5 - Turns on and off after a few seconds

Referred to datasheet of that IC, and REGN is 6V.

EDIT: Downloaded a similar schematic from this thread: https://www.badcaps.net/forum/showthread.php?p=1083332

[DanFen]

Re: Acer Spin 5 - Turns on and off after a few seconds

I checked them in beep mode, and disregarded the reading. Maybe that's why I thought they're short. Resistance is 3.2 on lowest scale.

At this stage everything is disconnected from the mainboard, including battery, RAM, m.2 SSD, and the rest.

For some odd reason at one point it stayed on but nothing on screen, now it's doing the same thing but no display.

Unfortunately I don't have the schematics for this board.

No. Most likely the caps are fine as the measurements may be misunderstood. You are checking the resistance to ground values ?

What is the scale used on your multimeter ? Use the lowest scale.

What are the resistance readings in ohms ?

CPU rails = low voltage rails and low voltage rails are often low in resistance, by design.

Having the logo up is a good sign.

A few suggestions:

1) Remove the battery and drives, etc. to remove them from the equation.

2) Boot up normally -> confirm you see the logo on the display screen.


Focus on sheet 44 of the schematic = TI Charger IC (PU4403).

3) Check the voltage @ 19V_DCBATOUT - what is the voltage ?

4) After the logic board shuts down, review this 19V_DCBATOUT voltage again. Measurement ?

5) What is the voltage on pin # 24 (PWR_CHG_REGN) of PU4403 charger IC ?

[mon2]

Re: Acer Spin 5 - Turns on and off after a few seconds

the caps behind the CPU all seem shorted out. If this is the case, would it still display the logo?

No. Most likely the caps are fine as the measurements may be misunderstood. You are checking the resistance to ground values ?

What is the scale used on your multimeter ? Use the lowest scale.

What are the resistance readings in ohms ?

CPU rails = low voltage rails and low voltage rails are often low in resistance, by design.

Having the logo up is a good sign.

A few suggestions:

1) Remove the battery and drives, etc. to remove them from the equation.

2) Boot up normally -> confirm you see the logo on the display screen.


Focus on sheet 44 of the schematic = TI Charger IC (PU4403).

3) Check the voltage @ 19V_DCBATOUT - what is the voltage ?

4) After the logic board shuts down, review this 19V_DCBATOUT voltage again. Measurement ?

5) What is the voltage on pin # 24 (PWR_CHG_REGN) of PU4403 charger IC ?

[DanFen]

I have an Acer Aspire Spin 5 that turns on, displays the Acer logo, and turns back off. This happens in approximately 5 seconds. It won't turn on by itself after that, it stays off.

The mainboard is Drift_SKL 16801-1M.

I've already tried disconnecting everything, including the battery. I've also removed the CMOS battery for a while, and still no luck.

The only thing I could find is that the caps behind the CPU all seem shorted out. If this is the case, would it still display the logo?

Other than this, I also noticed that the voltage around the CPU (after it power off) keeps fluctuating between ~0.3V - ~0.9V. Measured at one of the coils. Other than this I don't know what else I can check.

Thank you in advance for any help.