Lenovo G50-70 - power on problem

[SMDFlea]

Re: Lenovo G50-70 - power on problem

PQ204 And PU1208 aren't on pcb.

Yes, my mistake .

[DeniS182]

Re: Lenovo G50-70 - power on problem

I can't find problem, have someone any idea? Thanks

[mcplslg123]

Re: Lenovo G50-70 - power on problem

I feel your IT8586E is either not properly soldered, or bad flash or the chip itself is bad. Remember, whatever we order online, these chips are not new(majority case). So i'll suggest before discarding this particular case if you another ite8586, try it once. I had similar problems and ultimately the so called new ite chip was bad. You never know with these cheap chinese stuff....

[SMDFlea]

Re: Lenovo G50-70 - power on problem

It could be the KBC as suggested by mcplslg123 ,try this before replacing it though,Check everything on ADAPTER_ID_ON# ,PR322 voltage on both pins ,PC1266, PD304, PQ995 if they`re on the board ...

[DeniS182]

Re: Lenovo G50-70 - power on problem

IT8586 is soldered properly, I also mean my problem is in bad flash or chip itself. I need to buy programmer and then try it with other chip.

SMDFlea: these components aren't on board

[mcplslg123]

Re: Lenovo G50-70 - power on problem

IT8586 is soldered properly, I also mean my problem is in bad flash or chip itself. I need to buy programmer and then try it with other chip.

SMDFlea: these components aren't on board

You said at the outset that you replaced IT8586. If you dont have programmer for kbc, how do you programmed it?? Without programming it wont work

[mcplslg123]

Re: Lenovo G50-70 - power on problem

Sorry denis, i re-read your post-it was programmed chip.

[DeniS182]

Re: Lenovo G50-70 - power on problem

Today I reprogramm KB controller and laptop is now on, but with no picture, only black screen. I don't have voltage on +VGA_CORE, on gates of mosfets also and PIN 8 ENABLE signal on ISL62771HRTZ should be 3.3V? because I have zero here. I attached right schematic for NM-A271.

[MJ-meo-dmt]

Re: Lenovo G50-70 - power on problem

Is PXS_PWREN even coming from PCH? (MCP in schematic DDI, EDP section) There are many places where it goes....

[DeniS182]

Re: Lenovo G50-70 - power on problem

I inject 3.3V to 8pin enable and I have 1V on vga_core but still black screen.
+0.95VSP_VGA and +1.8VSP_VGA/1A are here.

[MJ-meo-dmt]

Re: Lenovo G50-70 - power on problem

And you get VGA_PWRGD signal at EC? When you inject?

[DeniS182]

Re: Lenovo G50-70 - power on problem

yes pin 85 EC - 3V

[MJ-meo-dmt]

Re: Lenovo G50-70 - power on problem

@DeniS182 Uhm... I'm busy here with a HP board giving me random start/not working shit... so my mind is fluttered with shit atm but uhm... Did you make sure that you have the suspected powerup states. See page/sheet 18

[SMDFlea]

Re: Lenovo G50-70 - power on problem

Did you flash a good bios with clean ME ,does the fan spin .

[DeniS182]

Re: Lenovo G50-70 - power on problem

I tried two dumps I don't know if ME is clean or not. Fan spin 1sec after laptop power on and after few seconds spin normally.

[SMDFlea]

Re: Lenovo G50-70 - power on problem

Post your original bios backup if you have it.It has your DMI info/win key .

[DeniS182]

Re: Lenovo G50-70 - power on problem

I attached my backup of bios

[SMDFlea]

Re: Lenovo G50-70 - power on problem

try this bios and ec.,latest versions.If it doesn`t work its back to more testing.

[DeniS182]

Re: Lenovo G50-70 - power on problem

I flashed main and ec bios. Now led and fan only spin for 1 second, then turns off and again, again.. it's turning on and off.

[DeniS182]

Re: Lenovo G50-70 - power on problem

I removed PJ702 now motherboard have vga_core voltage without injection, led is still on, fan not spinning. Before PJ702 I have 1.05VS, after PJ702 there isn't short, this rail only have 90-100mA current consumtion.