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820-4924-a not turning on, with over sensitive trackpad
- Thread starter Yoel Ren
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Post voltages on the big coils (secondary power supplies).
Do you get VCORE?
If yes, test for USB activity.
Do you get VCORE?
If yes, test for USB activity.
i got 12.6 on all big coil, cpu does get warm, c4691 and c4690 is missing, so I replaced it, u8080 and c8080 is missing too, and i placed it, now when i turn it on, the trackpad can click normally, but still no display, i got a fan spin, and i can toggle the caps lock light on and off..
https://boards.rossmanngroup.com/fo...924-green-light-orange-light-no-boot-no-power
from that link, I realize that my q7130 and the circuit is shorted to ground too, does it mean the cpu is alr deaD?
from that link, I realize that my q7130 and the circuit is shorted to ground too, does it mean the cpu is alr deaD?
Wrong assumption!
You have correct PPBUS_G3H, no short at all.
But is only one big coil there, L7130.
You probably got confused with big capacitors.
If trackpad clicks and CPU warms, probably all voltages are good, but I expected you post them.
And still wait to confirm USB activity.
Did you try external video?
You have correct PPBUS_G3H, no short at all.
But is only one big coil there, L7130.
You probably got confused with big capacitors.
If trackpad clicks and CPU warms, probably all voltages are good, but I expected you post them.
And still wait to confirm USB activity.
Did you try external video?
yeah i mistake the big capacitor with the coil, but the voltage is still 12.6v
is mouse light count as usb activity ? because it light on the mouse
havent try external video, i assume there's would not be a display because i don here a chime?
i will post all the voltage in a moment
is mouse light count as usb activity ? because it light on the mouse
havent try external video, i assume there's would not be a display because i don here a chime?
i will post all the voltage in a moment
ppbus_g3h : 12.6v
pp3v42 : 3.4v
ppvrtc_g3h : 3.3v
pp5v_s5 : 5.18v
pp5v_s3 : 5.18v
pp5v_s0 : 5.18v
pp3v3_s5: 3.3v
pp3v3_s4 : 3.3v
pp3v3_s3 : 3.3v
pp3v3_s0 : 3.3v
pp1v2_cpu_Ddr : 1.18v
ppddr3_s3_reg : 1.18v
pp1v8_s3_reg_r : 0v
ppvtt_ddr_s3 : 0.6v
pp1v05_s0 : 1.05v
I don't know why when I try to measure ppvcc, the board kind of go cold, doesnt produce heat from the cpu anymore
pp3v42 : 3.4v
ppvrtc_g3h : 3.3v
pp5v_s5 : 5.18v
pp5v_s3 : 5.18v
pp5v_s0 : 5.18v
pp3v3_s5: 3.3v
pp3v3_s4 : 3.3v
pp3v3_s3 : 3.3v
pp3v3_s0 : 3.3v
pp1v2_cpu_Ddr : 1.18v
ppddr3_s3_reg : 1.18v
pp1v8_s3_reg_r : 0v
ppvtt_ddr_s3 : 0.6v
pp1v05_s0 : 1.05v
I don't know why when I try to measure ppvcc, the board kind of go cold, doesnt produce heat from the cpu anymore
If mouse gets light if disconnect/reconnect with boad started, PROBABLY exists USB activity.
To CONFIRM 100%, use an OSX pendrive with Link LED; if flashes, that is.
Check if pins 28-30/J8300 get 5V in the first seconds.
Voltage should appear even without LCD; but will drop after few seconds.
Did you try known good LCD assembly?
To CONFIRM 100%, use an OSX pendrive with Link LED; if flashes, that is.
Check if pins 28-30/J8300 get 5V in the first seconds.
Voltage should appear even without LCD; but will drop after few seconds.
Did you try known good LCD assembly?
yeah i have a good known assembly, but there's no 5v there in the first second..
can I flash some light at the apple logo for retina lcd ?
if there is a green capslock, does it mean the board absoulutely turning on ?, if it is, I should be checkoing for no display right now..
can I flash some light at the apple logo for retina lcd ?
if there is a green capslock, does it mean the board absoulutely turning on ?, if it is, I should be checkoing for no display right now..
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Put DMM probe on L8300, power on the board and wait 10s.
If no voltage appear at all, check in same mode for pin 2/U8300.
If no voltage appear at all, check in same mode for pin 2/U8300.
"i got 4.5v at pin 2/ u8300"
So U8300 is enabled.
Check if gets 5V_S4 and all surrounded components.
If all good, change it.
Be sure no short on pin 5.
So U8300 is enabled.
Check if gets 5V_S4 and all surrounded components.
If all good, change it.
Be sure no short on pin 5.