Acer aspire 4736z KALG0 LA449P (not turning on)

[crazypepe]

Hi guys

Acer aspire 4736z KALG0 LA449P not turning on but there is power
But charge light near power switch is on
Checked power switch pin1 its 17.30v, and when pressed turns to 0v
Then back to 17.30v
Is that normal???

Replaced nec/tokin 0e907 with 4x330uf tantalum caps

Please help

Thanks in advance guys

[tomodachi]

Re: Acer aspire 4736z KALG0 LA449P (not turning on)

Hi guys

Acer aspire 4736z KALG0 LA449P not turning on but there is power
But charge light near power switch is on
Checked power switch pin1 its 17.30v, and when pressed turns to 0v
Then back to 17.30v
Is that normal???

Replaced nec/tokin 0e907 with 4x330uf tantalum caps

Please help

Thanks in advance guys

Checked power switch pin1 its 17.30v, and when pressed turns to 0v
Then back to 17.30v
Is that normal???

this voltage drop is normal, start with checking B+ rails one by one, probably you will find a short.

[infosquadsn]

Re: Acer aspire 4736z KALG0 LA449P (not turning on)

In normal conditions, when the power button is pressed, the EC controller got the ON/OFF signal and response with EC_ON signal, this one will activate the Q122 and kill the 17V line (51ON#), in that moment you will be permanently 3V on the power button.

Check the U57, change or rewrite it. This flash memory brings the code that is used by Ec controller to work.

sorry my poor english

good luck.