macbook 820 2879 PP18V5_DCIN_CONN move up and down ...

aprendiz

Moderator
Resistance between pins!!!!, put one probe on pin 17 and the other on pin 18, what is the resistance between those 2 pins, same thing for pins 27 and 28...
 

funtotos

Member
yes ! Voltage drops from 12 to 3 after a while . 2 seconde

i come back tomorow, i go to sleep
thanks you for your help
 
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funtotos

Member
Yes, the battery is present , light orange
pin 17, 18 = 3.1 ohm
pin 27, 28 = 20.2 ohm
 
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funtotos

Member
ground its OK around u7200 (resistance and capacitor )

u7200 voltages :
1) 0v
2) 0v
3) 2v - 0v
4) 3.34v - 0.700v
5) 0v
6) 0v
7) 0v
8) 3.34v - 0.700v
9) 3.34v - 2.60v
10) 186mv - 0.1mv
11) 186mv - 0.1mv
12) 4.1mv - 0v
13) 3.38v - 0.334v
14) 2.17v - 0.1v
15) 0v
16) 12.64v - 3.00v
17) 5.02v - 3.60v
18) 46.5mv
19) 0v
20) 0v
21) 1.2mv - 0v
22) 4.55v - 2.60v
23) 1.2mv - 0v
24) 1.2mv - 0v

PP3V42_G3H : 3.42v
PPDCIN_S5_S5 : 16.75v - 17.20v
PPBUS_G3H : 12.64v - 3.01v
 
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dukefawks

Administrator
You did not answer the resistance to GND on L7220. Also if the battery is charging I'm pretty sure 3v will be present on L7220 with the battery connected and charging, check that too.
 

dukefawks

Administrator
It is likely that is will power on if the battery has some charge. See if it powers on after the battery is charged a bit. Short the pads on the board to exclude a bad keyboard.
 

funtotos

Member
green light and orange won't turn on
i check voltage around u7200 with battery connected .


1) 0v
2) 0v
3) 2.3v
4) 3.34v
5) 2.01v
6) 0.741v
7) 3.34v
8) 3.34v
9) 7.87v
10) 3.43v
11) 3.34v
12) 0.220v
13) 3.38v
14) 2.01v
15) 0
16) 12.66v
17) 5.04v
18) 30mv
19) 0v
20) 0v
21) 0v
22) 4.56v
23) 0v
24) 0v

thanks you
 
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