iMac G4 15'' 1GHz - LCD White/Gray, No Speaker, No power led

[Henrique Guidi]

Hi guys, I need help, please ...

I have a 15 '' iMac G4 (USB 2.0) with 15 '' that was working before I opened it to clean and update.

Now, when I press the power button, the speaker is not working (no chime), the LCD is white/gray and the power led (white led) is also not working.

The quick answer would be "burnt logic board". However, using a headset, I can hear macOS 10.4.11 chiming and booting. I can even change the volume using the USB keyboard.

I am still waiting for a VGA cable to check if the video output is working, but I believe it works.

Did you face something similar? Have an idea on how to fix it? I have a spare iMAC G4 800 to be used to test something, but just replacing the LCD the result was worse: no video / black screen, no power, no speaker.

Thank you!!
Henrique Guidi


PS.: What I did wrong when I opened it? Well... I broke the PIN 1 of the TMDS connector (video connector) didn't see it and turned the machine on🤦‍♂️

 

[Henrique Guidi]

Just an update: the VGA cable came today and the external video is working fine, as I suspected.

I'm using this post to choose between trying to fix that somehow OR, if the issue is really only in the motherboard, try to use the LCD for something else, like an external monitor or a Hackintosh.

 

[Henrique Guidi]

Just for reference: https://discussions.apple.com/thread/2210520

It looks like I'm not alone trying to find a solution. However, it is pointing to a partially dead logic board =/