Clevo W670SJ /W650SJ - PowerOn light is on but nothing works

[WinUser]

Hello all and greetings from germany ,
I have a strange notebook here, a clevo W670SJQ1, motherboard is a W650SJ. Problem is: When press the PowerButton, the PowerOn light goes green (on) but nothing happens - no Fan spinning, no HardDisk Spinning. Notebook stay in this status until i press the PowerButton again for ~4 sec to power down.
Battery Charging works fine (LED goes orange, when its full it goes to green).


I have many experience in notebook and graphic-card repairs (many years)
but the thing here is a mystery to me . I have many equipment like hotair station, thermal camera, experience in bga reballing (with leaded solder balls and stencils)

So, i checked on the dismounted motherboard:
- all coils for short - nothing, all coils not shortet to ground
- 19V is present on all PowerRail Mosfets
- @19V when the notebook is complet off it draw round 2mA. when powerbutton is presed and notebook is in On state it draw only 36mA@19V...
- in this PowerOn State - nothing gets unusually warm, only Super IO Chip and PCH will heat up about 3-6 ° C warmer than the environment (thermalcamera view)
- no 5V, CPU or GPU powerrails goes on

Weired things:
- in off state - on the PowerButton there is 18.5V (i know only 3.3V on other notebooks). This voltage will short to ground when press the powerbutton and the powerOn LED will light on (green). when the system is on, there is only 17V on the powerbutton
- when powered on - the only "rail" that will switch on is the PCH, it becomes round 1.3V, but i think its not the VCC for the PCH (then the PCH must getting hotter i think)
- bevor this here happens - the system was often reset in the bootup-process (windows-start) like short power-off automaticly power on and start windows...or it will stuck in this "boot-loop" until i manual power off the system and power on again, then it have run fine...but no - nothing mor happens

so, what can be the problem here? any tips for me?

[WinUser]

Re: Clevo W670SJ /W650SJ - PowerOn light is on but nothing works

*edit* i figured out that the 3.3V Powerrail is always on, and the 5V rail goes on (also on USB, but not on ODD/HDD) when powering on the notebook.
1.3V also present on RAM, but ram dont get warm (also testet with another ram)

[WinUser]

Re: Clevo W670SJ /W650SJ - PowerOn light is on but nothing works

ServiceManual here

I do not know how the startup process works, what elements becomes a poweron signal...what to measure now...the other repaired notebooks hase only simple errors like capacitor short, or blown mosfet, but this notebook here is a harder case.

[piernov]

Re: Clevo W670SJ /W650SJ - PowerOn light is on but nothing works

Either measure all power rails, or at least check some checkpoints in the power sequence as I'm not sure what state the board is in.

Measure voltage just after triggering power button.

RSMRST#
SUSC#
SUSB#
ALL_SYS_PWRGD
SYS_PWROK

[WinUser]

Re: Clevo W670SJ /W650SJ - PowerOn light is on but nothing works

hello piernov, thanks for help

question: can i measure the voltage diretly on ITE SuperIO? when i look at the schematics, some voltage will go in, and some go out...but when a voltage is "generate" by PCH - how can i measure it? its a BGA chip. Test points not shown in schematics

[piernov]

Re: Clevo W670SJ /W650SJ - PowerOn light is on but nothing works

Measure on any components as long as it's the same line. Use the easiest to find and to put the probes on.

[WinUser]

Re: Clevo W670SJ /W650SJ - PowerOn light is on but nothing works

ok, here the measurements:
RSMRST# 3.25V directly on ITE SuperIO
SUSC# 3.25V directly on ITE SuperIO
SUSB# 3.25V directly on ITE SuperIO
ALL_SYS_PWRGD 0V directly on ITE SuperIO
SYS_PWROK 0V
PWR_SW 3.25V directly on ITE SuperIO

1.05V_LAN_PWRGD 3.3V
DDR1.5V_PWRGD 3.3V
1.05VM_PWRGD 3.3V
PM_MPWROK 3.3V
V1.05M_POERGO_AND 3.3V
PCH1.5VS_PWRGD 0V
DELAY_PWRGD 0V
PM_PCH_PWROK 0.9V
PCH_PWROK 0V

G5310 (1.5VS, servicemanual page 97 )
EN_SKIP 0V


so, the PCH1.5VS_PWRGD signal is fail, in the schematics, the mosfet PQ19 on page 97 also, is blocking the enable signal for the G5310 buck Converter (1.5V PCH). PQ19 Gate have 3.3V on it...so now, i must see why.


weired thing...the PWR_SW out from the ITE SIO deliver 3.3V...but on the poweron button i have 19V...i havnt look why, i think ther is near the poweron switch a transistor...but - i dont know why this...


but now - i must looking why PCH buck-converter is not powering on... anny suggestions?

[piernov]

Re: Clevo W670SJ /W650SJ - PowerOn light is on but nothing works

So it's getting into an S0 but ALL_SYS_PWRGD is missing due to an issue on an S0 rail. PCH1.5VS_PWRGD indeed is missing.

SUSB is supposed to be low as SUSB# is high. See PQ23B circuit.

Some platforms will have B+ on the power button, dunno on this one, maybe ok.

[WinUser]

Re: Clevo W670SJ /W650SJ - PowerOn light is on but nothing works

GOT IT
notebook repaired...
N Channel Dual Mosfet MTDN7002ZHS6R (Location PQ23) was broken...its a "inverter" for DD_ON# and SUSB...but on SUSB the Drain stays high although the gate was also high...

swapet with a other one in stock - a 2N7002KDW - and now it boot up like a charm

The broken MTDN7002ZHS6R was "half broken" - never seen...when gate high, the 3.3V over 10k on Drain was only droped down to round 2.7V...not enough.


So, notebook works.

thanks for help

[qonma]

Re: Clevo W670SJ /W650SJ - PowerOn light is on but nothing works

good post

[AmuroRay]

I have the same problem with this laptop. Is it normal if the switch on pin 1 voltage is 19v? I have changed the mosfet in pq23 because it was faulty and the laptop bootup fine, but there is another problem, the laptop will shut down and start on repeatedly until i turn it off.

[AmuroRay]

I think i fix it, it was bad bios. I reflashed the bios using tl866ii plus programmer and also flash ec firmware, the laptop now working good again. Thank you..