Previously it doesn't had vsus. So I replaced the KB with KB9012QF and then all Power, HDD, WIFI LEDS were blinking when i plugged in charger.
After that I have change KB with KB930QF as schematic said KB9012QF=KB930QF.
Thereafter everythings ok but when i plugged in adaptor no lights blinking but laptop doesn't turn on. charging IC voltages are as below.

VIN=19.1v
P1= 0.02v
P2=4.69v
PQ9 AND PQ10 gates has 0v

PU4=BQ24725 PINOUT

PIN5 = 0V
PIN4 = 0V
PIN3= 0V

PIN20= 18.8V
PIN8 and PIN9 = has readings not sure:p (checked with oscilloscope and i have no experience previously with oscilloscope )

I'd try to replace PU4, because KB doesn't take part in this block of scheme. B+ should be even without KB.
- What is OK? You have no voltage on input.
If you say, that was lost after replacing KB, than what stops from getting old KB back?

New KB9012QF without EC FirmWare

KB930QF and KB9012QF not interchangeable, since KB930QF has an external firmware while the firmware inside KB9012QF

I said "everythings ok" meant after replacing KB there were no blinking LEDs :D
Are you sure B+ should be there even without KB?
Also after i went through KB9012QF, i figured out KB930QF and KB 9012QF are not interchangeable. I dont have spare KB9012QF right now. So I'll have to wait for few days.


Yes "siberian". I figured after went through the KB9012QF datasheet they are not interchangeable. Cz KB9012QF has 128K embedded flash. Do we need to do something with that after replacing KB9012QF? I mean reprogramming the firmware?

yes, you need programm it. And you'll be need a special programmer, which support it EC.
like viewtopic.php?f=170&t=16421 or SPI TT (http://ejtag.ru/shop.php?cat=1#4 )

Thanks for the advice. But in this laptop there are two IC s for Main BIOS and EC (U36 and U42). Therefore do we need to reprogram "128K embedded flash" on KB9012QF? I means with that there 3 firmwares.

or we need to re program only U36 and U42? I have seen some are selling programmed KB9012QF for aspire V3, E1, Samsung and Lenovo models.
I am really confused here Cz usually we only re program main BIOS and EC.

P.S. I cannot buy anywhere else other than ebay. Cz they ship items for my country. If you can plz let me know some links in ebay cz i didnt find it (kb9012 programmer) there.

No, it's ME + BIOS

Are you saying U36 and U42 is for ME+BIOS.....?

Could you plz explain about this ME furthermore..? Is it means Management Engine something? I really don't know what is it.

After you said that I understand there are 3 progrmmable chips in Acer Aspire V3-571 MB

U36, U42 and KB9012QF..... What are the chip do i have to reprogram then? I mean which one is Main BIOS and which one is EC?

4MB - MAIN BIOS
2MB - Managment Engine fw (intel part)
128kB in KB9012 insyde - EC fw

if you change 9012, you will need to program EC fw into it. 128kB

Thanks for the explanation. I have SOFI SP8-A USB programmer and shall I program kb9012 by using it?
also i need to know whether firmware programming is perform when kb9012 on the motherboard or off the motherboard?
Basically I want to know how to program KB9012.

Problem was in PQ8 which was the reverse input protection circuit. It has ground the Adapter voltage when the adapter is in. but When i used fully charged battery, laptop turns on and working well. I have replace this PQ8 many time but within 3 or 4 months it became defective again and again. Therefore it is good to remove it to eliminate this problem in future but there will be no protection circuit. Thanks.