Acer Aspire 5740G: how to flash KBC BIOS (reasons - no power, doesn't charge, no LED)
Laptop recovery by flashing KBC BIOS (MX25L1005) using a programmer.
I have already described the process of flashing BIOS in the article Lenovo IdeaPad B560 with similar symptoms so I'll skip this part of the explanation. The chip itself MX5L1005 (the one you need flash) is located right next to the super I/O Nuvoton WPC876xL or WPCE77nx or NPCE78mx.
Acer Aspire 5740G motherboard MBPM601002 48.4GD01.01M 09285-1M
Before you rush into soldering the chip out and flashing it with the programmer you have to make sure that the problem is in the BIOS. To do this we need a digital oscilloscope (I use Rigol DS1052E 50MHz). In order to check the BIOS you have to connect one end of the oscilloscope to the first leg of the BIOS chip.
Now watch the oscilloscope.
No data exchange. Most likely the firmware is crashed. So we flash the firmware using the programmer -.
Now we solder the chip back, connect power supply and try looking for data exchange again.
Data exchange detected! Now reassemble… reconnect… and done - notebook restored.
Important notice: do not repair or modify this device if it's still under warranty.