Originally Posted by wizardknight

I had a reading of 0 on one of my phones. I replaced the whole lcd and reused the ribbon if memory serves me right. If you don't want to invest any money I think that FRX07.1 rom does not use the light sensor, and can be ran off the sd card. That would let you use the phone as is.

I ordered a replacement LCD/Digitizer and put it in and there is absolutely no change. Can it be anything else other than the flex cable where the light sensor is? What now?

There are only two other options. Bad cable or bad system board. I have never heard of a system board with that kind of a problem.
You are not using a case are you? I have seen cases that cover the spot where the light sensor is on the lcd. I had to drill a hole in one once.

Also did you get a new or used lcd. Maybe someone was getting rid of a lcd that worked, but had a bad light sensor.

Originally Posted by wizardknight

There are only two other options. Bad cable or bad system board. I have never heard of a system board with that kind of a problem.
You are not using a case are you? I have seen cases that cover the spot where the light sensor is on the lcd. I had to drill a hole in one once.

Also did you get a new or used lcd. Maybe someone was getting rid of a lcd that worked, but had a bad light sensor.

I am not using a case.

Both replacement LCD/Digitizers were reconditioned. But I think the light sensor is not part of the LCD -- it is on the flex cable, right?

Is it possible that something in the firmware is no longer properly accessing the light sensor? Does it make sense to try to load a different build in before going to another flex cable?

The strange part is that normal screen power function stopped right when the LCD was replaced--that's what makes me think it is hardware and not the firmware. But what would cause a light sensor to all of a sudden stop functioning?

And then again, is it definitely the light sensor which makes the screen power toggle non-functional?

Originally Posted by jazzer1971

I am not using a case.

Both replacement LCD/Digitizers were reconditioned. But I think the light sensor is not part of the LCD -- it is on the flex cable, right?

Is it possible that something in the firmware is no longer properly accessing the light sensor? Does it make sense to try to load a different build in before going to another flex cable?

The strange part is that normal screen power function stopped right when the LCD was replaced--that's what makes me think it is hardware and not the firmware. But what would cause a light sensor to all of a sudden stop functioning?

And then again, is it definitely the light sensor which makes the screen power toggle non-functional?

The light sensor is part of the lcd. If you hold it up to a very bright light you can make out it't oval shaped location at the top of the lcd screen.
There is no harm in changing the rom. It doesn't cost anything. I would have tried that first off though.
You could try re-seating the cable. It could be off.
I do not know what causes light sensors to fail, but I know they do from time to time.
All that fails replace the cable, and hope for the best.

Originally Posted by wizardknight

The light sensor is part of the lcd. If you hold it up to a very bright light you can make out it't oval shaped location at the top of the lcd screen.
There is no harm in changing the rom. It doesn't cost anything. I would have tried that first off though.
You could try re-seating the cable. It could be off.
I do not know what causes light sensors to fail, but I know they do from time to time.
All that fails replace the cable, and hope for the best.

The oval shaped opening is just a clear part of the digitizer. That allows the light to pass through to the sensor which is soldered on the upper part of the flex cable. The oval is only covered on the very top layer of adhesive where the HTC logo is--all the other layers are clear. I've got a torn apart digitizer to verify that as well as an LCD/Digitizer in tact that is outside the phone. Inspecting them under a microscope shows nothing but clear plastic.

So it looks like flex cable is next after some firmware experiments.

Originally Posted by jazzer1971

The oval shaped opening is just a clear part of the digitizer. That allows the light to pass through to the sensor which is soldered on the upper part of the flex cable. The oval is only covered on the very top layer of adhesive where the HTC logo is--all the other layers are clear. I've got a torn apart digitizer to verify that as well as an LCD/Digitizer in tact that is outside the phone. Inspecting them under a microscope shows nothing but clear plastic.

So it looks like flex cable is next after some firmware experiments.

did your flex cable end up being the issue?

No good news

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Originally Posted by supermaxkato

did your flex cable end up being the issue?

I don't yet know but I tried all the advice in this post.
http://forum.xda-developers.com/show...3&postcount=20

Multiple Task29 runs followed by a load of ManilaRUSH and then more Task29 then SleekBasic to get rid of the sense. Nothing will bring this screen back on. Installing LUMOS I still get readings of 0 on the light sensor.

I think I have to go and order a flex cable at this point. Give me another couple of weeks to answer your question. If this doesn't work I will be out more than $50 trying to fix this thing after a new LCD and a new flex cable.

Flex cable / light sensor culprit

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Replaced the flex cable and normal phone functionality was immediately restored! Bottom line is you cannot easily operate one of these phones without a working light sensor--its functionality is tightly wound into the suspend and sleep options.