Screen black but external works OK
I'm debating on whether this is a dead LCD display or a bad video controller. Since the external display work (VGA adapter to Dell 19").
System Profile does not detect any displays connected, though the external connection *does* work.
I've found the video adapter 661-4673 for about $190, and this is definitely the cheaper of the 2 components. A replacement LCD is about 3x that. :(
I checked the graphics ROM version and it matches the newer version mentioned in the Apple support doc DL71
Any suggestions on diagnosing this further?
This had been running 10.5 and I'm in the process of upgrading to 10.6.
Esta é uma boa pergunta?
3 comentários
I've removed the glass and bezel and have the LCD display in-hand. With the LVDS cable disconnected and the inverter cables connected, is it correct that the CCFL bulbs should light? What voltage should I be getting from the inverter?
por Charles S
I measured the voltage from the inverter at 0.14 V AC. This seems wrong. I tried powering on with only the inverter cables plugged in and the bulbs did not light.
I then tried with only the LVDS connect and I was able to see the Apple logo and spinning wheel then it went blank. I can't reproduce this now, though.
Is there some sensor involved with powering the inverter when the display is detected? Could the temperature sensor be preventing the LCD from getting power and thus preventing the inverter from getting power too?
I found a 2nd graphics FW update in Apple support doc DL938 but that won't install either.
It would be good to know:
* Does the inverter get power regardless of a display connected?
* What voltage should the inverter be producing?
* What effect does the temperature sensor have?
* Could a PRAM issue be causing the display to not be detected?
* Can I force a reinstall of either of the graphics FW updates?
por Charles S
Some scheduled updates install firmware so I won't worry about them not installing. It's good you took the time to double check.
por Dan