Jump to content

Macintosh TV not powering on (MLB issue)

Recommended Posts

I have a Macintosh TV that has power, but will not chime or boot with its MLB. With a known-good Color Classic MLB installed, it will chime and boot okay, though there is an intermittent fluttering sound coming from the speakers. That might just be an issue with the CC board though. I cleaned it up but it needs caps replaced too. 


There wasn't obvious cap leakage, but I cleaned the board and replaced the MLB caps anyway. The symptom remained the same. On flick of the power switch you can hear the display power on, but when the power key is pressed, no LED on the keyboard and no chime or boot on the computer.


I installed a new PRAM battery on the original board, but that didn't change the symptom. And the machine boots with the CC board without a PRAM battery installed.


The analog board also looks okay at first inspection. No obvious cap leaks.


So, what should be checked next?


Edited by elemenoh
Link to post
Share on other sites

On many of my 5xx chassis AIO boards, I've had issues with battery goop having corroded the traces on or around the CUDA chip. Resoldering (or replacing this chip using a suitable similar donor mac) usually fixes the problem right away.


One of my MacTVs also had a trace corroded through UNDER the battery holder- so its worth desoldering and inspecting that as well.

Link to post
Share on other sites
  • 2 weeks later...

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...