Re: DG424/DG524 NM-B301 Rev 1.0 no display and power issue
My earlier point of view may be incorrect.
The EC is creating (driving) the signal with netname EC_RSMRST#. That is, the EC is in control of this reset line and the EC is keeping this line low using one of its GPIO pins. This may be due to the EC not working / not being powered / not being clocked / corrupt firmware used by the EC.
Remove all power, what is the resistance to ground of EC_RSMRST# ?
On your logic board, do you have the resistor stuffed @ RC9350 ?
Do you have the power rails present on the EC?
What are the voltage to ground readings of the following signals?
EC_SMB_CK0
EC_SMB_DA0
The EC is creating (driving) the signal with netname EC_RSMRST#. That is, the EC is in control of this reset line and the EC is keeping this line low using one of its GPIO pins. This may be due to the EC not working / not being powered / not being clocked / corrupt firmware used by the EC.
Remove all power, what is the resistance to ground of EC_RSMRST# ?
On your logic board, do you have the resistor stuffed @ RC9350 ?
Do you have the power rails present on the EC?
What are the voltage to ground readings of the following signals?
EC_SMB_CK0
EC_SMB_DA0
PMIC_SMB_CLK0
PMIC_SMB_DAT0
Tommorow sir I can check this signal , im on day off righnow
Can you confirm this voltage to ground? It does not look correct.
See attached. This status line should be ~3v (max).
What is the voltage to ground of your +3VALW rail ?
I already check this before I poted it here its about 2kilioms and going up to ground, so not shorted Im sure about that. Is it normal to have pulsing?
Re: DG424/DG524 NM-B301 Rev 1.0 no display and power issue
ALW_PWRGD - 3.3v - 3.9v is it normal ?
No, this rail should not be so high since the pull-up voltage is to +3VALW.
The +3VALW rail is created by PU401. Specifically, confirm that the FB leg of PU401 indeed has a 1k resistor as shown in the schematic.
Do not power up the board if the FB circuits are ever missing else the output may overshoot and kill every part that is voltage sensitive and operates from the +3VALW rail.
Remove the solder blob @ PJ402 to isolate all downstream (aka consumer) circuits from this power rail.
Power up again. Confirm that you have stable +3v3 @ PL401. If you do not, replace PU401.
If you observe fluctuations on the power good line then +3VALW is not stable.
At +3v9 output on +3VALW, this may have caused damage for voltage critical parts.
No, this rail should not be so high since the pull-up voltage is to +3VALW.
The +3VALW rail is created by PU401. Specifically, confirm that the FB leg of PU401 indeed has a 1k resistor as shown in the schematic.
Do not power up the board if the FB circuits are ever missing else the output may overshoot and kill every part that is voltage sensitive and operates from the +3VALW rail.
Remove the solder blob @ PJ402 to isolate all downstream (aka consumer) circuits from this power rail.
Power up again. Confirm that you have stable +3v3 @ PL401. If you do not, replace PU401.
If you observe fluctuations on the power good line then +3VALW is not stable.
At +3v9 output on +3VALW, this may have caused damage for voltage critical parts.
PR405 is present and 1K value is correct
REMOVE jumper PJ402
test PL401 stable 3.4v
there is a pulsing on the ALW_PWRGD Im getting 4.5 to 4.8v
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