Asus g53 dead

[Francisco.s]

Hi all, I'm trying to repair an Asus laptop (g53jw) that doesn't power up.
It has 19 volts in all pwm circuits (to power them), and 3,3 volts in power button.
I'm trying to find out EC-BIOS chip, but I can see only the main BIOS, (Winbond 25032BVSIG) and this one, have no power volts in its pin 8.
The problem is that I haven't the schematic for this motherboard., and it's difficult to follow the circuit without it.
In the Asus webpage, there is only a bios file to download, (G53JWAS.209) and it is only 2 Mbytes long. (bios chip is 4 Mbytes or 32 Mbits)
Any help will be appreciated.
Regards.

[Francisco.s]

Re: Asus g53 dead

I have made some more research, and apparently, data for EC-BIOS and main BIOS are both in the same chip. (Winbond 25032BVSIG)
It has 3,3 volts in pin 8 of bios chip, but not last more than 1 second, and during that time I can see some burst pulses in pin 1,2 and 5.
Next step would be de-solder bios chip, and reprogram it with new data, but as I mention in previous post, the size of bios chip, doesn't match the one I have downloaded from Asus website.
I need a bios dump from a functional laptop.
Anyone?
Thanks.

The schematic will also be helpful.

[Francisco.s]

Re: Asus g53 dead

Finally, the problem seems to be in the signal "ME_SusPwrDnAck", wich links pin 106 of embedded controller and pin "M1" of PCH. (IBEXPEAK-M)
Looking at the power sequence (page 94 and 95) in the schematic, (is not the same schematic) This signal have to reach 3 volts in order to make other voltages to be established.
This signal have a relative very low ohms, (600 ohms) and have a pull-up resistor of 10 Kohms, so it is very likely that one of the mentioned chip, has a little leakage.
Regard.

[whaldsz]

Re: Asus g53 dead

what is the voltage of EC_RST# upon plugging in the charger?

pin 3, 7, 8 of BIOS Chip is 3.3V?

[Francisco.s]

Re: Asus g53 dead

what is the voltage of EC_RST# upon plugging in the charger?

pin 3, 7, 8 of BIOS Chip is 3.3V?

EC_RST# is in high level from the very beginning, and if I short it to gnd, then a reset occurs, and at this time, voltage in bios flash are correct. (of course there is no pulses in SPI bus)
When EC_RST# is high again, voltage in pin 8 of bios flash, become zero in one second or so, but first I can see some pulses in SPI bus.
Regards.

[whaldsz]

Re: Asus g53 dead

I can see a timing issue.

You mentioned that you the board only have one BIOS? But your schematic has two?

Is your RTC Battery ok? +3VA stable (see page 81 +3VA_AEC)?

You may need to resolder the SIO chip.

[Francisco.s]

Re: Asus g53 dead

You mentioned that you the board only have one BIOS? But your schematic has two

Yes, this schematic has two bios chips. I can´t find any better, but this circuit seems to be almost equal.

Is your RTC Battery ok? +3VA stable

yes, RTC Battery is ok.

You may need to resolder the SIO chip

Solders looks good, but it is an easy job, I´ll do it.

What do you think about ME_SusPwrDnAck signal?
Thanks.

[whaldsz]

Re: Asus g53 dead

Yes, this schematic has two bios chips. I can´t find any better, but this circuit seems to be almost equal.



yes, RTC Battery is ok.



Solders looks good, but it is an easy job, I´ll do it.

What do you think about ME_SusPwrDnAck signal?
Thanks.

Looking at page 30 on ME_SusPwrDnAck circuit, im not sure if it's the same with your board. ME_SusPwrDnAck should be LOW so that ME_SusPwrDnAck_EC becomes HIGH (through Q3002).

[Francisco.s]

Re: Asus g53 dead

Looking at page 30 on ME_SusPwrDnAck circuit, im not sure if it's the same with your board. ME_SusPwrDnAck should be LOW so that ME_SusPwrDnAck_EC becomes HIGH (through Q3002).

I couldn't find Q3002 or R3074, (it's an Asus) but these low resistance in this signal, makes me think that there is some problem inside any of those chips mentioned before.
I will try to cut the connection in-between, and perhaps I could determine which one has the leakage.

[costin_yo]

Re: Asus g53 dead

Hello guys, I have the same laptop Asus G53, someone inverted the polarity of the charger and inserted it into the laptop while it was already ON. The laptop turns on but I cant find any damaged part of it. I tend to believe that is the bios that is faulty or something.
I have the same bios as the person above. (Winbond 25032BVSIG).
I have the following voltage in the bios chip:
pin 1: 3.47v
pin 2: 3.47v
pin 3: 3.47v
pin 4: 0v
pin 5: 3.47v
pin 6: 3.47v
pin 7: 0v
pin 8: 0v

Please let me know where do you think the problem might be. I do not have any display image but I had it before when I removed the cmos battery and it froze on the Asus logo image. Now I have a blank screen and the power led is on (the fans are working too). Thank you and I kindly wait for a reply.

[labtechec]

Re: Asus g53 dead

Finally, the problem seems to be in the signal "ME_SusPwrDnAck", wich links pin 106 of embedded controller and pin "M1" of PCH. (IBEXPEAK-M)
Looking at the power sequence (page 94 and 95) in the schematic, (is not the same schematic) This signal have to reach 3 volts in order to make other voltages to be established.
This signal have a relative very low ohms, (600 ohms) and have a pull-up resistor of 10 Kohms, so it is very likely that one of the mentioned chip, has a little leakage.
Regard.

PLS Refer This http://www.xinxunwei.com/bjbwx/201511164939.html