Macbook Air A1466
Logic board:820-3437B
Problem: It came as dead-no light at all on magsafe.
Steps taken:On observation under microscope, Found U1900 badly corroded on pin1-2-3-4. Desoldered the Ic, cleaned the tracks and resoldered it. No corrosion anywhere else, no liquid damage. MB started,fan spinned and there was chime,I turned it off & left it on the table overnight.Next morning the mb refuses to start-magsafe remains green(not going orange) and no fan spin. Consumption fluctuating up and down from 0.008A to 0.330A on dc bench supply. Lifted U1900 again and cleaned , resoldered but no joy.
SMC_BC_ACOK:3.3V
U7100-DC-IN-16V
PPVRTC_G3H-3.3V
PPBUS_G3h/PPV3V42_G3H-OK
PP5V_S5-keep pulsing from 1.5V to 5V(PROBLEM)
Resistance on PP5V_S5-45K and on diode mode-OL.
I've replaced U7501 and flashed known good bios with clean me but problem remains.
I dont have much experience on mac's and dont repair them on regular basis. Need help guys.
PS: I'm using genuine magsafe245W cable for bench supply. Tried with genuine magsafe245W adapter as well.
Logic board:820-3437B
Problem: It came as dead-no light at all on magsafe.
Steps taken:On observation under microscope, Found U1900 badly corroded on pin1-2-3-4. Desoldered the Ic, cleaned the tracks and resoldered it. No corrosion anywhere else, no liquid damage. MB started,fan spinned and there was chime,I turned it off & left it on the table overnight.Next morning the mb refuses to start-magsafe remains green(not going orange) and no fan spin. Consumption fluctuating up and down from 0.008A to 0.330A on dc bench supply. Lifted U1900 again and cleaned , resoldered but no joy.
SMC_BC_ACOK:3.3V
U7100-DC-IN-16V
PPVRTC_G3H-3.3V
PPBUS_G3h/PPV3V42_G3H-OK
PP5V_S5-keep pulsing from 1.5V to 5V(PROBLEM)
Resistance on PP5V_S5-45K and on diode mode-OL.
I've replaced U7501 and flashed known good bios with clean me but problem remains.
I dont have much experience on mac's and dont repair them on regular basis. Need help guys.
PS: I'm using genuine magsafe245W cable for bench supply. Tried with genuine magsafe245W adapter as well.
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