Acer Aspire 5810T Completely dead, no lights at all.

[Andreasbest]

Hello.
This is my 3rd and last laptop that is completely dead, the schematics are a bit crap so if you have anything better or some knowledge to donate i will appreciate it
So i have 19v at U63 (A04407) in both sides, i have 19v at U12 (A04407) in Drain side and on all Source pins.Gate has 1,7v.
I also got 3v to the power switch.
Other notices : The charger is 3 pin and appears broken, i get voltage from a regular 2 pin charger from another Acer.

[BlueMidnight]

Re: Acer Aspire 5810T Completely dead, no lights at all.

The schematic only shows the main board. The DC jack and 3V/5V chip, etc. are on a separate board called the "MINI Board". They put each board in its own schematic. I'm attaching the schematic for that one.

First, check the 3V/5V chip. Since it's on the back side of that mini board, the easiest way to check the outputs (without removing the board from the case) is at the inductors L24 and L25. The 3V for the power button comes from the linear 3V output and not the switching 3V output. So we want to check that the switching outputs are working.

[Andreasbest]

Re: Acer Aspire 5810T Completely dead, no lights at all.

No voltage at all at L24 and L25.
Now i'm trying to found U58 but i don't see it anywhere....
Is there a chance to require only the 3pin charger that came with from factory?
Never seen a charger like this in Acer again.

[BlueMidnight]

Re: Acer Aspire 5810T Completely dead, no lights at all.

The schematic I gave you is only for that DC-IN board labeled "MINI Board". The schematic you provided is for the main board (the one with the CPU, RAM, etc). There are also at least two other boards connected through ribbon cables. Each board has its own PDF.

This is going to be a similar situation to the first one I helped you with. You are going to have to remove the main board and the mini board from the case and then (while keeping them connected together), plug in the AC adapter. Then, measure all the pins of the 3V/5V chip (U58). Also check all the outputs for shorts.

[Andreasbest]

Re: Acer Aspire 5810T Completely dead, no lights at all.

I hope i measure the correct direction as they are not marked with numbers like Toshiba, i did it counter clockwise.
1 0
2 0
3 2
4 3.3
5 0
6 0
7 0
8 3.3
9 4.5
10 0
11 0
12 0
13 1.2
14 3.3
15 0
16 19
17 4.5
18 0
19 0
20 0
21 0
22 4
23 0
24 0
Only outputs with mainboard and miniboard is one USB and the RJ45 that both are not shorted (pins in position and straight).

[BlueMidnight]

Re: Acer Aspire 5810T Completely dead, no lights at all.

Yes, pins are always numbered counter-clockwise (except for some random 3pin components I've seen).

You'll be checking for shorts on the outputs of U58. The switching outputs can be easily checked at the inductors L24 and L25. The linear outputs can be checked at pins 8 and 17.

But it looks like U58 is not even being told to turn on. So let's investigate that signal. Measure all pins on Q11 and Q12 (they both have 6 pins and are located very close to U58).

[Andreasbest]

Re: Acer Aspire 5810T Completely dead, no lights at all.

No shortcircuit at 8 and 17 pins.
Both Q11 and Q12 have 5v at pins 5 and 6, all other 0v.

[BlueMidnight]

Re: Acer Aspire 5810T Completely dead, no lights at all.

Okay, still no signal there. We'll have to go farther back. The source of the signal to turn on the 3V/5V switching regulators is pin 15 of U16 (the EC/SIO/Keyboard Controller). It's on the main board and is a giant chip with the word "Winbond" on it. Actually, the easiest way to measure it is to measure the voltage at resistor R73 instead (both sides of it). The attached photo shows the location.

[whaldsz]

Re: Acer Aspire 5810T Completely dead, no lights at all.

No shortcircuit at 8 and 17 pins.
Both Q11 and Q12 have 5v at pins 5 and 6, all other 0v.

There's a button (SW2, page 10 in the schematic), you can push it force 3V/5V_EN to go HIGH.

Have you checked U62, U61, U60, AND U59 for leaks or shorts?

[BlueMidnight]

Re: Acer Aspire 5810T Completely dead, no lights at all.

SW2 does allow you to forcibly enable all the outputs so you can test the mini board without it being connected to the main board. But when you aren't getting the enable signal from the main board, you don't need to wonder why you have no 3V/5V switching outputs -- you need to wonder why you don't have the signal that enables them.

[Andreasbest]

Re: Acer Aspire 5810T Completely dead, no lights at all.

Hello again, got some connection problems but now all set.
So my mainboard is a little different than photo.Please check the picture.
I found R73 on the other side, not sure if still the resistor we want since the board is different, but i got no voltage on both pins.

[BlueMidnight]

Re: Acer Aspire 5810T Completely dead, no lights at all.

I found a better schematic for your board. It looks like the other one is for the version with a separate GPU. That does change things a little. The pin you need to check is still pin 15 though. Don't worry about the resistor unless you get voltage at pin 15 because it's not right next to the pin like on the other version of the board. It's R214 and it is on the opposite side of the board.

[Andreasbest]

Re: Acer Aspire 5810T Completely dead, no lights at all.

No voltage at pin 15, no voltage at R214 both sides.

[Andreasbest]

Re: Acer Aspire 5810T Completely dead, no lights at all.

Any other thoughts?

[BlueMidnight]

Re: Acer Aspire 5810T Completely dead, no lights at all.

So the 3V/5V outputs truly are being told to stay off. Next, test some other voltages:

All 3 pins of Q8

Also, on the EC/KBC/SIO chip (U13):
Pin 85 (ECRST#)
Pin 93 (AC_IN#)

[Andreasbest]

Re: Acer Aspire 5810T Completely dead, no lights at all.

On Q8 i get 3.3v only at Collector (rest 0v) and on U13 i get 3.3v as well at pin 85 and 0v at pin 93
No AC_IN? What the heck?

[Andreasbest]

Re: Acer Aspire 5810T Completely dead, no lights at all.

I don't have AC_IN neither in BTB1 connector, is this a chance that this model requires the 3 pin (ID) charger that came with and cannot work with the usual 2 pin?

[BlueMidnight]

Re: Acer Aspire 5810T Completely dead, no lights at all.

It just uses 2 wires in the AC adapter. But the center hole has a thin piece of metal on each side of the hole. If the plastic is broken off, it might look like it has 2 pins inside and also the surrounding ground connection. But the 2 pins inside are connected together. The jack on the motherboard has an extra detection pin but that just touches the ground on the barrel connector to detect physical insertion of the adapter. There's nothing special about the AC adapter itself.

The AC_IN# signal is actually okay. The '#' in "AC_IN#" means it's an "active low" signal. So, 0V means active/present/yes/true, etc. If you follow that circuit (on page 8 of the mini board schematic) you will see that it does indeed go to 0V when there is AC adapter voltage (i.e. when AC_OK goes high).

The first thing I would do is make sure (with power disconnected) there is no short between the 3V/5V_EN line and ground. It's possible that a component (e.g. Q11/Q12 on the mini board) could be shorted to ground. If not, then it must be the EC pulling it to 0V.

If there is no short, then the problem may be with the EC itself, corrupted firmware, or an inability to read the BIOS chip properly (in this notebook, the same chip holds both the BIOS and the EC firmware).

If you have the means, you can try backing up and then flashing the EC firmware. I don't have a copy of it unfortunately, but a copy might be on this forum or elsewhere. This would also confirm the flash chip itself is good.

[Andreasbest]

Re: Acer Aspire 5810T Completely dead, no lights at all.

I tried the pin 15 of U13 that has 3V/5V_EN, no short circuit.
However i tried Q11 and Q12 and both have short circuit with the ground to pin 1 and pin 4.

[BlueMidnight]

Re: Acer Aspire 5810T Completely dead, no lights at all.

That's okay. Pins 1 and 4 are supposed to be connected directly to ground.