So. My brain is a bit unfocused today, but here are my thoughts having read the other comments and letting it marinate.
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# I would check the battery connector, just in case. I have seen issues where a unit will only charge when the screen is on, which is usually related to a bent/damaged battery connector pin. But I think in those cases the iPad will at least power on. It just won't charge unless the display is on. Even so, worth a look. There are also some lines which go from this connector to components which interface directly with lines from the battery connector. I might even take a look at that area of the board since those components all lie directly in between the questionable display connector and the battery connector.
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I would check the battery connector, just in case. I have seen issues where a unit will only charge when the screen is on, which is usually related to a bent/damaged battery connector pin. But I think in those cases the iPad will at least power on. It just won't charge unless the display is on. Even so, worth a look. There are also some lines which go from this connector to components which interface directly with lines from the battery connector. I might even take a look at that area of the board since those components all lie directly in between the questionable display connector and the battery connector.
[image|2630970]
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# I am less likely to think this is an SOC issue. Maybe yes, if it was powering and booting properly with all the connectors in place, just no image. I2C lines, having 1.8V is a good start, but I2C is a data communication protocol which means that chips on either end send or receive specific patterns of voltage pulses. And the pulses are likely too brief for a multi meter to detect or display in real time anyways. That's what an oscilloscope would be more useful for. Having the voltage there doesn't necessarily mean the communication is occurring, or is occurring correctly. I am more likely to think this is an issue with something in the power up sequence. Like it's getting to a certain point, hitting a problem and then restarting hoping the problem was resolved, but it wasn't.
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I am less likely to think this is an SOC issue. Maybe yes, if it was powering and booting properly with all the connectors in place, just no image. I2C lines, having 1.8V is a good start, but I2C is a data communication protocol which means that chips on either end send or receive specific patterns of voltage pulses. And the pulses are likely too brief for a multi meter to detect or display in real time anyways. That's what an oscilloscope would be more useful for. Having the voltage there doesn't necessarily mean the communication is occurring, or is occurring correctly. I am more likely to think this is an issue with something in the power up sequence. Like it's getting to a certain point, hitting a problem and then restarting hoping the problem was resolved, but it wasn't.
So. My brain is a bit unfocused today, but here are my thoughts having read the other comments and letting it marinate.
# I would check the battery connector, just in case. I have seen issues where a unit will only charge when the screen is on, which is usually related to a bent/damaged battery connector pin. But I think in those cases the iPad will at least power on. It just won't charge unless the display is on. Even so, worth a look. There are also some lines which go from this connector to components which interface directly with lines from the battery connector. I might even take a look at that area of the board since those components all lie directly in between the questionable display connector and the battery connector.
[image|2630970]
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# I am less likely to think this is an SOC issue. Maybe yes, if it was powering and booting properly with all the connectors in place, just no image. I2C lines, having 1.8V is a good start, but I2C is a data communication protocol which means that chips on either end send or receive specific patterns of voltage pulses. And the pulses are likely too brief for a multi meter to detect or display in real time anyways. That's what an oscilloscope would be more useful for. Having the voltage there doesn't necessarily mean the communication is occurring, or is occurring correctly. I am more likely to think this is an issue with something in the power up sequence. Like it's getting to a certain point, hitting a problem and then restarting hoping the problem was resolved, but it wasn't.
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