Hi dear friends., I am working on a Apple MacBook Pro A1708 , Logic Board 820-00840-A that has no backlight. The logic board powers on fine, but no display. After Checking on the backlight driver chip, I found that the EDP_BKL_EN is missing. And this Power Enable comes from the PCH. So does this means this Logic board cannot be repaired & brought back to life again? The resistance from GRD to the test point of EDP_BKL_EN is around is 0.66M ohms. R8442 (0ohms) is ok. Any suggestion/Tip if any would really appreciate.
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Remove Q9908 and U8400 and chk resistance before giving up.Give it a try
Good luck -
Is the display known to be good? they have a common problem with the flexible backlight cableComment
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I have a lot of T resistance boards (LCD logic board) & even slightly broken screen for this model. & I even used a Known good LCD, still the same, no difference, thanks PITERPENYComment
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is there an image? since the backlight will not turn on if there is no image! Have you checked the J8500 lines?EDP_INT_AUX_N and EDP_INT_AUX_P ok?Comment
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I get the image dear... I have a bare bone screen & I use a powerful LED torch to get a backlight. I see the Apple logo & the then folder clearly. & what is this for "EDP_INT_AUX_N and EDP_INT_AUX_P ok?"Comment
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Connect via HDMI to external monitor, check internal display is detected and you can vary brightness up and down. Try a PRAM reset, also check I2C lines are pulled up to 5V.Comment
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Vizio e601i-A3 - Has Sound and Display, But No Backlight - Bad Power Supply Board or Bad LED Bulbs ?I was given this TV from my great uncle. He said it just wouldn't turn on one day out of nowhere, replaced the TV, and gave it to me to possibly fix and use for myself.
Upon bringing it home and plugging it up, it showed a standby light.
I powered it on and without a flashlight, the display showed the "V" but the lighting is very dim, but visible.
The screen seems to blackout and stay black, but with a flashlight I can see the display.
With my Playstation 4 connected via HDMI, and running a game I can hear sound.
Assuming... -
Hi good Friends., today working on a Macbook Pro A2289, Logic board 820-01978-A. The history was liquid spill, Cleaned & replaced all corroded components & now the logic board shows 20v & .01amp on the meter. Not taking in any amps. Upon trouble shooting I get the required stable voltages 5V, PP3V3_G3H 3.3V but no PP3V3_S5. Checked the schematic, assume that this is generated from U7800. Checked all the Input/Output voltages on this chip. All is fine, except PP3V3_S5 is missing. Resistance from GND to PP3V3_S5 is 146 Kohms. First I need to make sure whether PP3V3_S5 is generated from... -
Hi, this is my personal laptop, which the original board (lets call it Board A) blew up PU8700 (TPS51486), making a hole on the board, i had left the laptop at my desk one day with the battery fully charged and didn't touch it for a week, but when i tried to turn it on it didn't
Thought the battery was dead, so i plugged in the charger then tried to power on, the power LED blinked once, charged LED still orange, unplugged the charger, plugged in again and I noticed the "magic smoke" smell, so i unplugged the charger, removed the back cover and saw the blown IC (the "magic... -
I hope this is the right forum to post in despite not technically being a repair, but still a question of swapping boards.
I thought I'd explore the possibility to upgrade an existing working Samsung ue55nu7096u with the logic board (and power board if needed) of a newer model (ue55ru7105k) of the same size and appearance (and resolution). The reason being I'd like the extra inputs of that board including component in, an extra HDMI port and bluetooth. Its panel is broken so I have no use for the board otherwise.
The models launched in 2018 and 2019 respectively.... -
Hello, First of all thanks you for reading this topic.
I need your help with identify missing parts on trackpad logic board (661-18430).
The liquid got into the orange area, but I found that the green area had some parts missing or burnt.
Please help me with identity parts from blue and red area .
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