persists.

LED # 4 is LED # 4 is Off: The video card and logic board are unable to communicate to generate video. Replace the video card and install the iMac Graphics Firmware Update.. If the issue persists, replace the LCD display.

Video Corruption on the Panel

1.Make sure all software updates have been applied to the computer. Refer to KBase article 303903, Intel-based iMac: Installing available updates , and to Apple Downloads for all available updates for the iMac (Mid 2007) model of computers.

2.Connect an external monitor to the mini-DVI port. Does the external display exhibit the same color tinting?

Yes: Replace the video card and install the iMac Graphics Firmware Update.

No: Check the LVDS cable connections. If connected properly and the same color tinting persists, replace the LVDS cable. Does color tinting persist after changing the LVDS cable?

Yes: Replace the LCD display panel.

No: Problem solved. Restart the computer from the Apple menu and make sure the computer display is functioning correctly.

Display is tinted another color.

1.The iMac (Mid 2007) computer has a tinted glass panel covering the display, giving it a new look from previous models. Make sure this not what the customer is referring to.

2.Reset the parameter RAM. Press the Command-Option-P-R keys. When you keep all the keys held down, you will hear the startup chime over and over again (about every ten seconds) until you let go. After you hear the second chime, you can let go of the keys.

Does the computer display video after successfully resetting the computer’s PRAM? Yes: Problem resolved. Restart the computer from the Apple menu and make sure the computer display is no longer tinted another color.

No: Continue to the next step.

3.Connect an external monitor to the mini-DVI port. Does the external display exhibit the same color tinting?

Yes: Replace the video card and install the iMac Graphics Firmware Update

No: Check the LVDS cable connections. If connected properly and the same color tinting persists, replace the LVDS cable. Does color tinting persist after changing the LVDS cable?

Yes: Replace the LCD display panel.

No: Problem solved. Restart the computer from the Apple menu and make sure the computer display is no longer tinted another color.

System Shuts Down

Unexpected Shutdown or Freezes

1.If the computer freezes or you experience unexpected shutdowns while using your

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Apple 24-inch mid 2007 manual System Shuts Down, Video Corruption on the Panel, Display is tinted another color