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820-3115
I found burnt transistor or mosfet (3 pin chip) on dc jack on 820-2565 dc jack board.
I tested main board with another dc jack but same story. CPU core appear only for 1 seg at 1.12V
I compared all coils with another board 820-2879 and only found differen value at L7260. In faulty...
- Only with battery dosnot power PPBUS - 11.50V
-Only with AC adapter it power and works. PPBUS - 12.30 (too low? Bad SMC?)
- WIth ac adapter and battery it power and works. PPBUS - 12.30
If I remove battery it works 10 seconds more and shutdown. Already tried a new battery.
ISL 17,18 and 27,18...
A1278 2011
with ac adapter work ok
with ac adapter and battery work ok
with only battery run slow. When write something, letters appears 4,5 seg. later. Any idea?
Recived this macbook. Board: 820-3023
When I press power no video, but I can see how mouse light up for 2 seg and off and on and off again and so on. I check the board and found cracked ram. Could be that the problem?
Ram is written: J2108BCSE-DJ-F
1148R937F90
Also I cannot find where to buy...
Asus X55VD
KBC: IT8517
I have 3V at power button. They goes to 0V when press power.
It charges main battery, altought I have only 3V there and goes up.
I dont have any schamatic for IT8517 so cannot check if powrtbtn# goes from KBC to PCH. Is there any schematic that I can use?
In Quanta R13 board I have external video, and all works ok.
But on lvds screen I have only backlight and no video. Already tried new screen and new lvds cable. Also convert this board to UMA and still the same.
If I have backlight does it mean GPU or CPU video is enable already and this mean...
820-3115 light damage board arround lvds only.
With ac adapter and battery it power up.
Only with battery it power up.
Only with ac adapter (no battery) it doesnot power up and I have 12.56V, ISL6259 - ACOK - 3.33V. Also 17,18 and 27,28 are ok at 3ohm and 20ohm in ISL6259
If I connect battery...
820-3115 missing =PPVCORE_S0_CPU_REG
This is light liquid damage board. I check all coils and I only found missing PPVCORE at 0V
I checked U7400 and I have
CPUIMVP_VR_ON - 3.3V
PP5V_S0_CPUIMVP_VCC - 5V
What is next to check?
820-2936 board. I dont have another board do swap and customer want to fix the thunderbolt.
I have 0.5V at D3895 pin 1,2 and 0.582 diode mode after and 0.532 before- D3895
T29_A_HV_EN_R - 0V so I miss enable. I tested with thunderbolt connected with good known hdd with OS X.
Could be bad U3890...
PPBUS_G3H - jump from 12.72V to 3.8V and again to 12.72 and again to 3.8V and so on.
I found R7052 is bad but it is under a glue. I cleaned the glue and I checked again and now it is ok - 0 ohm
PPBUS now is 12.57V. Now laptop works.
Only thing I did is clean the glue. But I dont think this is...
Liquid board arround lvds. I replaced lvds connector and reflowd some areas. LVDS and screen was also damaged so I replaced LCD cable and screen too.
Now I have video but there is noise like in the image. When boot to OS X is worst (red noise). I checked lvds again and it is solder well. Any...
I miss Pwrbtn# - 0V. It comes from PCH and goes to KBC. KBC recived 3-0-3V from power button, lid - 3V, 3V power is present.
I know pwrbtn# pull up resistor is in PCH, and KBC just short pwrbtn# to ground when power button is pressed. But I am not sure if KBC is bad, so it always short pwrbtn#...
820-3437 missing backlight
Liquid damage arround lvds. I replaced LVDS connector and now I have 39.6V at lvds pin 3,4. I can see blinking folder using lantern.
39.6V is enought? This mean U7701 (LP8550) is working well?
Board 820-3330
Magsafe is blinking.
25 seg - OFF
6 seg - ON
ADAPTER_SENSE - 3.3V always
PP18V5_DCIN_FUSE - 16.6V Always
Diode mode:
DCIN – 1 and 1
PPVBUS-G3H – 1 and 464
Any idea why magsafe is blinking? Already tried 2 dc boards. PP18V5_DCIN_FUSE too low?