[help]asus gl703ge dead, no shorts!

[phantomEVO]

Hi! i have an asus gl703ge totallt dead.

no shorts connected to power bench

i've not 3,3 nor 5v...

you can donwload boardview/schematic here

https://www.badcaps.net/forum/showthread.php?p=1052820


pu28 has not 3,3 and 5v out...it has voltage in, but i have no en1 and en2

en1 and en 2 are "s5_on" and are coming from Ec IT8987...

is it 8987 preprogrammed? should i try to change it?

thanks

[mon2]

Re: [help]asus gl703ge dead, no shorts!

Remove all power. Measure the resistance to ground of these missing power rails. Need to check if the output coils of PU28 are being shorted.

Post each measurement.

[phantomEVO]

Re: [help]asus gl703ge dead, no shorts!

pl21 and pl22 output (+5v_s5 and +3_s5) are not shorted

so what's next?

i've 5v on ldo 5 and 3v on ldo 3

[mcplslg123]

Re: [help]asus gl703ge dead, no shorts!

S5_ON will be released by EC if all basic requiremnts of EC is met. So i'll suggest to check basic requirement of EC like VCC/AVCC/VSTBY/Vbat/EC_RST#/RSMRST#/AC_IN etc. IT8987E is programmable.

[phantomEVO]

Re: [help]asus gl703ge dead, no shorts!

So it Could be an EC problrm?

I have not voltage on vcc of ec

[mon2]

Re: [help]asus gl703ge dead, no shorts!

What is the voltage to ground of +3VPCU ?

[mcplslg123]

Re: [help]asus gl703ge dead, no shorts!

VCC of EC is powered by +3VPCU as @mon2 has already highlighted. Go with his advice. However, with VCC being present, EC is not supposed to release S5_ON. Basic checks most often solves a problem.

[phantomEVO]

Re: [help]asus gl703ge dead, no shorts!

What is the voltage to ground of +3VPCU ?

3,2v present (pin 50) but no vcc on pin 11 of it8987

[phantomEVO]

Re: [help]asus gl703ge dead, no shorts!

how is it possible? -.-'

[mon2]

Re: [help]asus gl703ge dead, no shorts!

These are separate sequenced power rails.

Review the voltages on PU30. This part is the creator of the +3V that is missing on pin 11 of the ITE EC.

Post all voltage measurements to ground on PU30.

[reformatt]

Re: [help]asus gl703ge dead, no shorts!

You won't get anything out of PU30 till you have S5_ON from the EC to enable 3V_S5.

Review pg56 of the schematic which has the power sequencing. As @mcplslg123 stated, go through your pre-requisites first for the EC by paying attention to the sequence. Check signals +3V_RTC, RTC_RST#, AC_IN, +3V_PCU. Also pay attention to EC_WRST# (which should be high).

S5_ON is pulled up to +3VPCU_KBC by KR30, it will only be low if the EC is pulling it down (or there is problem in this part of the cct). If the above signals are ok, then I'd be looking at reprogramming the EC. It does load it's EC from the main BIOS, but I think this may only happen when the EC is blank.

[phantomEVO]

Re: [help]asus gl703ge dead, no shorts!

These are separate sequenced power rails.

Review the voltages on PU30. This part is the creator of the +3V that is missing on pin 11 of the ITE EC.

Post all voltage measurements to ground on PU30.

i have not any voltage on pu30..

3,3v +3V_RTC on R1052
3,3v RTC_RST# on r1029
3,2v 3VPCU on r869
0v EC_WRST# on kr6

[mon2]

Re: [help]asus gl703ge dead, no shorts!

0v EC_WRST# on kr6

This is an active LOW signal since there is a # symbol as a suffix.

This means that with a 0v on this signal line, the EC is being parked in RESET mode. This line must return to a logic '1' = ~3v to allow for the EC to boot up its firmware. Often the ECs contain an internal 8051 microcontroller to perform the assorted tasks.

[phantomEVO]

Re: [help]asus gl703ge dead, no shorts!

so, what could i do?

[reformatt]

Re: [help]asus gl703ge dead, no shorts!

so, what could i do?

EC_RST# is connected to a simple delay circuit to ensure EC reset doesn't go high till about 100ms after +3VPCU_KBC appears (time constant is 0.1).

So obviously check the impedance of this line to ground for a short etc. If good, check continuity of KR6 to +3VPCU_KBC, and to pin 14 of the EC.

[phantomEVO]

Re: [help]asus gl703ge dead, no shorts!

i made a mistake: EC_WRST#is 3,2v, but i confirm i have 0v on pin 11 of EC (vcc)

ps i've found that PD3 is not present (burnt trace) and pq21 was replaced
i have 19v on the power jack, after second mosfet (pq21) i have 17,7 and not 19...i don't know if it is normal

[mon2]

Re: [help]asus gl703ge dead, no shorts!

Follow the suggestions on post #11.

Measure each voltage in the top-down order. Post where the sequence stops.

[phantomEVO]

Re: [help]asus gl703ge dead, no shorts!

I have read 200 Times page 56, i have also stamp this schemstic…but i don’t understand how to read it…

I don’t understand the order of those power output

Please Help me to understand!!

[mon2]

Re: [help]asus gl703ge dead, no shorts!

Each is a signal that must go from low to high before the next line below it can do the same.

So start with the top line.

If this line is say at 0 volts, then the next signal below it cannot work.

Starting with the top line, measure the voltage to ground. Stop if you see the a signal stuck at 0 volts.

We know that you have a valid voltage at +3VPCU so check the next line.

What is the voltage to ground of NBSWON# ?

[phantomEVO]

Re: [help]asus gl703ge dead, no shorts!

NBSWON# 2,4v