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MacBook Pro 13" 820-3115

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hamed57

New member
I have a macbook pro 13" with no backlight.
Everything else is working well.

My measurements:

backlight fuse: 12.55v
LVDS pin 21 and pin22: 12.54v
C9020 pin1: 12.52
C9020 pin2: 0.0

Board looks good under the microscope. I ultrasonic cleaned it and I slightly reflowed U9701.

Any hint at this point?
 
A

aprendiz

Moderator
Do you have image on the screen?? is yes check continuity between cathode of D9701 and ball A5 of U9701.....
 
H

hamed57

New member
aprendiz said:
Do you have image on the screen?? is yes check continuity between cathode of D9701 and ball A5 of U9701.....
Click to expand...

Hi, Thanks for the reply,

I have image on the display.
There is continuity between cathode of D9701 and ball A5 of U9701.
 
A

aprendiz

Moderator
all seems to be ok but U9701 is not boosting, replace U9701, when take off the IC, confirm continuity on feedback line.....
 
D

dukefawks

Administrator
Diode mode on the BKL output line? D9701 check for short? All the voltages are there so it must be in the U9701 boost circuit.
 
H

hamed57

New member
dukefawks said:
Diode mode on the BKL output line? D9701 check for short? All the voltages are there so it must be in the U9701 boost circuit.
Click to expand...

Hi, I don't know where can I get the measurement for "Diode mode on the BKL output line"
I did the diode mode between pin 21 and 22 and the ground and voltage drop is 0.605v
The is no short on D9701
 
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dukefawks

Administrator
No continuity between PPVOUT_SW_LCDBKLT_FB and pin 2 of l9701, look at diagram and tell me if this is correct or not.
Need to check continuity between LP8550 pin B1,B2 and L9701. Also pin A5 to D9701 K cathode.
 
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