arnonabuurs
New member
Hi I have an Air 820-3437 with no backlight computer is starting up though. R7715 and R7731 had a bit of corrosion on them so i replaced those. Now I am lacking Voltage on R7731 pin 1 -> PPVIN_S0SW_LCDBKLT. Where does this come from, is this derived from PPVIN_S0SW_LCDBKLT_FET Q7706? All looks good, R7788 and R7789 also OK. What voltage should I measure at EDP_BKLT_EN?
Thanks
Edit: some more voltages measured:
nothing on D7701
8.6v on Q7706 pin 3
Diode Mode on D7701 Pin 1 = 0.262v Pin 2 = 0.396
Nothing at R7704 BKL_PWM
R7731 Pin 2 = nothing (well, 25mv)
resistance to GND on BKL_PWM = 355v
Thanks
Edit: some more voltages measured:
nothing on D7701
8.6v on Q7706 pin 3
Diode Mode on D7701 Pin 1 = 0.262v Pin 2 = 0.396
Nothing at R7704 BKL_PWM
R7731 Pin 2 = nothing (well, 25mv)
resistance to GND on BKL_PWM = 355v
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