Motherboard DA0ZQ1MB8D0 Rev. D no turn on

[wzamoyski]

Hello everyone.

It's my first post on this forum (sorry for my English). I want to try fix my first motherboard and hope found solution.

I have problem:

• DA0ZQ1MB8Do Rev. D;
• Nuvoton NPCE78TLA0DX;
• BD82HMSS;
• I5-430M.

When I press power switch the motherboard not turning on, no leds - no reaction. I measurement:

Voltage:

• CN2 n. 1 - 0V
• PL3 - 0V
• PL6 - 3.60-4V (very strange)
• PL7 - 0V
• PL10 - 0V
• PL11 - 0V
• PL12 - 0V
• PL13 - 0V
• PL15 - 5.13V
• PL16 -3.38V
• PL17 - 0V
• PL18 - 0V

Resistance:

• PL3 - 221.7Ω
• PL6 - 8kΩ and high
• PL7 - 7.7Ω
• PL10 - 27.3Ω
• PL11 - 122.6Ω
• PL12 - 122.7Ω
• PL13 - 38.8Ω
• PL14 - 38.8Ω
• PL15 - 1kΩ and high
• PL16 - 40kΩ and slow
• PL17 - 44.6Ω
• PL18 - 205.8Ω

• U40 n. 8 - 4kΩ and higher
• U29 n. 8 - 1kΩ and higher

U40 have no power, I think (reading manual) probably is problem with KBC. Earlier have issue with fan - I follow this topic (reprogramming BIOS):

https://www.badcaps.net/forum/showthread.php?t=55264

Maybe you have idea, what to do next. Maybe I do something wrong.

Thanks.

[mon2]

Re: Motherboard DA0ZQ1MB8D0 Rev. D no turn on

Can you link or post the schematic if on this forum?

Check the voltage of the first 2 * dcin mosfets.

Which charger IC is onboard?

If the BQ charger IC, start with the voltage to ground of:

REGN
ACDRV

Pins. Post each measurement.

[mon2]

Re: Motherboard DA0ZQ1MB8D0 Rev. D no turn on

See attached. Measure the voltage to ground of these 3 points of interest. Post each reading.

[wzamoyski]

Re: Motherboard DA0ZQ1MB8D0 Rev. D no turn on

Hi @mon2. Thanks for reply.

Can you link or post the schematic if on this forum?

I use schematic from Quanta Zq1 and boardview (in attachement).

Which charger IC is onboard?

If the BQ charger IC, start with the voltage to ground of:

REGN
ACDRV

Thanks for help. After reading Your post I realize use wrong charger and changed it. Now when I press switch button, motherboard power on. I have blue ligt on LED1. But now have another issue - no fan spinning.
It's SL88731A. I checked:

• PIN 2 (ACIN) - 3.96V
• PIN 13 (ACOK) - 3.35V
• PIN 22 (DCIN) - 18.77V

See attached. Measure the voltage to ground of these 3 points of interest. Post each reading.

1 - 0V
2 - 3.34V
3 - 3.35v

[mon2]

Re: Motherboard DA0ZQ1MB8D0 Rev. D no turn on

What is the voltage to ground of VA and VA1 points ?

[wzamoyski]

Re: Motherboard DA0ZQ1MB8D0 Rev. D no turn on

what is the voltage to ground of va and va1 points ?

va - 19.46v
va1 - 19.15v

[mon2]

Re: Motherboard DA0ZQ1MB8D0 Rev. D no turn on

Remove all power. Measure the resistance to ground of pin #4 of PD32. If the resistance is not low, then consider to replace PD32.

[wzamoyski]

Re: Motherboard DA0ZQ1MB8D0 Rev. D no turn on

Remove all power. Measure the resistance to ground of pin #4 of PD32. If the resistance is not low, then consider to replace PD32.

I checked again every cable, connections. I saw, processor was no tightened into socket. Now motherboard turning on. Laptop works. Thanks @mon2 for suggestions and help.

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