Acer Swift 3 SF314-51 not powering up - leds flashing

[rddube]

Re: Acer Swift 3 not powering up - leds flashing

Still unsure what to do and which chip I should be measuring - some of the pins I can't see on the chips..scared to go on

[rddube]

Re: Acer Swift 3 not powering up - leds flashing

Attached are 2 closeup photos of the 2 chips mentionned below.

CPU VCore Power Stage Chip is U8002A in Schematic => SIC631CD-T1-GE3
CPU VCore Controller is U8000A in Schematic => ISL95859HRTZ

U8002A:
Pin 1 => PWM Input from ISL Chip.
Pin 32 => VIN = Battery/AC Voltage
Pin 3 => VCC = 5V

U8000A:
Pin 40 => Enable Input of the Controller. (this is what piernov was talking about)
Pin 34 => VCC = 5v
Pin 33 => VIN = Battery/AC Voltage

U8002A: I can see pin 1 and pin 3, but not pin 32 as this chip only has 24 pins?

U8000A: I only see 30 pins, probably some are under the chip?

So do I measure pin 1 and 3 of U8002A and check for changes while power cycling?

[rddube]

Re: Acer Swift 3 not powering up - leds flashing

I checked pin 1 and 3 of U8002A and before power cycling I get 2.5V on pin 1 and 5 volts on pin 3, no changes while power cycling, voltages are steady.

[KvnTM]

Re: Acer Swift 3 not powering up - leds flashing

I checked pin 1 and 3 of U8002A and before power cycling I get 2.5V on pin 1 and 5 volts on pin 3, no changes while power cycling, voltages are steady.

So there is something on the PWM Input. Do you have an oscilloscope to view he PWM Signal? It will be impossible to do with a multimeter.

This board is a mess. No part designators. Not really service friendly.

[rddube]

Re: Acer Swift 3 not powering up - leds flashing

Yes I have an oscilloscope (a very basic one, it's called a AllSun). It has an automatic setting so would I measure pin 1 and see what it gives? I can post a photo of the type of output.

[KvnTM]

Re: Acer Swift 3 not powering up - leds flashing

Yes I have an oscilloscope (a very basic one, it's called a AllSun). It has an automatic setting so would I measure pin 1 and see what it gives? I can post a photo of the type of output.

It should give you a square wave. Yes! Take a photo of it.

[rddube]

Re: Acer Swift 3 not powering up - leds flashing

All I get is a steady line, I am attaching a photo and a short video (in zip format) if you want to see.

Stays the same even if I power cycle the board.

Tks!

[rddube]

Re: Acer Swift 3 not powering up - leds flashing

Some one all ready have try to repair it one of the coils solder joints, try the power button it should get 3.3V does it goes high low #? What is your SIO ITEXXXX?

With the setup I have now, I do have 3.3V on the power button pin, and when I ground it, it goes low and comes back up to 3.3V.

[KvnTM]

Re: Acer Swift 3 not powering up - leds flashing

With the setup I have now, I do have 3.3V on the power button pin, and when I ground it, it goes low and comes back up to 3.3V.

Yes that's how it works. The EC detects when this line goes low thus the button has been pressed.

[rddube]

Re: Acer Swift 3 not powering up - leds flashing

Any ideas on what I should look at or try? Tks!


On pin 8 of U8002A I have 19V steady.

[rddube]

Re: Acer Swift 3 not powering up - leds flashing

@KvnTM Looking at the chip again, it is an ISL95859A HRTZ but in the schematics they show a ISL95859 HRTZ, which explains the difference in the number of pins. Can't seem to find a datasheet of the ISL95859A HRTZ anywhere, but maybe the pin configuration is different and I could check components that are at the output of the PWM_A? What do you think?

[rddube]

Re: Acer Swift 3 not powering up - leds flashing

I guess that no response is bad news, probably I should look for another motherboard?

[KvnTM]

Re: Acer Swift 3 not powering up - leds flashing

I guess that no response is bad news, probably I should look for another motherboard?

Sorry i was away for a bit

Do you know what the original owner already did to this board?
Let's go back a bit...

With AC: The Board will react to the power button and flash the led 5 times. Correct?

Without AC: The Board doesn't react to the power button and does absolutely nothing. Correct?

[rddube]

Re: Acer Swift 3 not powering up - leds flashing

]Hey KvnTM!

No actually it is the other way around, on battery (without AC) the board reacts to the power button and flashes 5 times the amber led. On AC, the blue amber led comes on steady and there is no reaction to the power button.

I have to tell you that when I removed the heatsink (see photo attached) I noticed paste on the CPU, but nothing on what I think is the GPU just beside it. So I think the GPU overheated with time and is probably shot?

Also I noticed on Ebay that they are selling the same board with the same CPU as defective in Spain [URL="[URL="https://www.ebay.ca/itm/Motherboard-Damaged-Acer-Aspire-Swift-SF314-51-i5-7200U-NB-GKK11-00F-Faulty/264417427727?hash=item3d9081c10f:g:KZYAAOSw-49dLFlh"]https://www.ebay.ca/itm/Motherboard-Damaged-Acer-Aspire-Swift-SF314-51-i5-7200U-NB-GKK11-00F-Faulty/264417427727?hash=item3d9081c10f:g:KZYAAOSw-49dLFlh[/URL"]https://www.ebay.ca/itm/Motherboard-Damaged-Acer-Aspire-Swift-SF314-51-i5-7200U-NB-GKK11-00F-Faulty/264417427727?hash=item3d9081c10f:g:KZYAAOSw-49dLFlh[/URL

What do you think?

[KvnTM]

Re: Acer Swift 3 not powering up - leds flashing

]Hey KvnTM!

No actually it is the other way around, on battery (without AC) the board reacts to the power button and flashes 5 times the amber led. On AC, the blue amber led comes on steady and there is no reaction to the power button.

I have to tell you that when I removed the heatsink (see photo attached) I noticed paste on the CPU, but nothing on what I think is the GPU just beside it. So I think the GPU overheated with time and is probably shot?

Also I noticed on Ebay that they are selling the same board with the same CPU as defective in Spain [URL="[URL="https://www.ebay.ca/itm/Motherboard-Damaged-Acer-Aspire-Swift-SF314-51-i5-7200U-NB-GKK11-00F-Faulty/264417427727?hash=item3d9081c10f:g:KZYAAOSw-49dLFlh"]https://www.ebay.ca/itm/Motherboard-Damaged-Acer-Aspire-Swift-SF314-51-i5-7200U-NB-GKK11-00F-Faulty/264417427727?hash=item3d9081c10f:g:KZYAAOSw-49dLFlh[/URL"]https://www.ebay.ca/itm/Motherboard-Damaged-Acer-Aspire-Swift-SF314-51-i5-7200U-NB-GKK11-00F-Faulty/264417427727?hash=item3d9081c10f:g:KZYAAOSw-49dLFlh[/URL

What do you think?

The small die is the PCH which isn't attached to the heatsink in many newer laptops. The GPU and CPU are together in the larger die.

Ususally the small die heats up immediately to untouchable temperatures if it's dead. Usually only with AC plugged in. I guess yours doesn't heat up?
I actually think there's something wrong with battery detection / charging.

EDIT: Do me a favor and measure voltage on Pin 17 of the EC. Theres a very very small possibility that the lid switch causes Problems. Do it on AC and on Battery only.

[rddube]

Re: Acer Swift 3 not powering up - leds flashing

You're right, it doesn't heat up that much with AC plugged in, about 2 degrees, same as CPU.

Yes there seems to be something going on between battery and AC powering, and when both are connected, I get no response from the power button, and only the blue light comes on steady. It once happened however that I got the blue and amber light on (just once) so I left it for a few hours thinking it was charging. When I unplugged AC a few hours later, I got the dreaded 5 flashes of the amber light

[rddube]

Re: Acer Swift 3 not powering up - leds flashing

Going on your feeling that it must be the charging section that has a problem, I reexamined the board and on the backside I found this chip with a hole in it!

It's hard to render on a photo, but it is an actual hole, photos attached. I tried to render it with different lighting so that you can see better.

Isn't that abnormal?

[mcplslg123]

Re: Acer Swift 3 not powering up - leds flashing

Going on your feeling that it must be the charging section that has a problem, I reexamined the board and on the backside I found this chip with a hole in it!

It's hard to render on a photo, but it is an actual hole, photos attached. I tried to render it with different lighting so that you can see better.

Isn't that abnormal?

Thats not a charging ic. Its a hdmi repeater. I'm afraid going by the symptoms, it may be the onboard cpu+pch die bad.

[rddube]

Re: Acer Swift 3 not powering up - leds flashing

Thats not a charging ic. Its a hdmi repeater. I'm afraid going by the symptoms, it may be the onboard cpu+pch die bad.

Hi, that means that the board is no good anymore as changing the cpu + pch is almost an impossible thing? Do you think if I attempted a reflow under controlled temperature it could work? Is there a solution, or time to sell it the laptop for parts? Tks!

[KvnTM]

Re: Acer Swift 3 not powering up - leds flashing

Hi, that means that the board is no good anymore as changing the cpu + pch is almost an impossible thing? Do you think if I attempted a reflow under controlled temperature it could work? Is there a solution, or time to sell it the laptop for parts? Tks!

If there is an actual hole in that chip some idiot probably injected a high voltage into a power rail. We know someone was "working" on it before since there was solder residue on the AC input caps.

If someone injected 18V into a 3.3v or 5v rail its pretty much game over

You could remove that chip because it is obviously dead. Maybe it shorts something which is important for the board to start. Who knows.

I actually still have some hope that the cpu isn't dead. vcore is not coming on and the pch isn't heating up or shorting the rail..
Reflowing would do nothing good. You'd have to replace the whole chip. And if someone really randomly injected voltage there's no point in fixing this. There would be too many blown chips.
I feel bad for this board...