back light problem on my acer es1-511

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Solution
If you have 3.3 volts on pins 1 and 5, and 0 volt on pins 2 and 4 for the U11 chip. This is the reason the backlight is OFF, you need 3.3 volts on pin 4 for the backlight to be ON. Right now the pin 2 is controlling the output for the U11. Pin 2 for the U11 is connected to the EC chip, so, what is controlling the EC to give 0 volt to pin 2 for the U11? This is why I asked to verify the voltages for the U14 chip.

Acer_Aspire_E_15_U14_p2_p3.jpg

If you have no voltage at pin 5 on the U11 chip, this means that the chip is not receiving the 3 volts switched. Measure the voltage at pin 4 and 5 on the U10 chip, it's just beside the LCD connector. The pins number is the same has U11. You are very patient with my requests.
 
If you have 3.3 volts on pins 1 and 5, and 0 volt on pins 2 and 4 for the U11 chip. This is the reason the backlight is OFF, you need 3.3 volts on pin 4 for the backlight to be ON. Right now the pin 2 is controlling the output for the U11. Pin 2 for the U11 is connected to the EC chip, so, what is controlling the EC to give 0 volt to pin 2 for the U11? This is why I asked to verify the voltages for the U14 chip.

Acer_Aspire_E_15_U14_p2_p3.jpg

 
Solution