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Classic II Analog Board with no -12V


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What I've done:  Classic II Analog and logic boards are both fully recapped, work triple+ checked. Replaced the original CNY17G-3 with a CNY17-3, the TDA4605 with TDA4605-3, replaced the DP 3 and 4 diodes and the IRFBC40 on the analog board. Reflowed 99% of joints on the back of the analog board.
 
The machine now boots, will load OS from scsi2sd, passes logic board diagnostic tests. I have solid and stable +12v and +5v on respective pins, but on pin 5 of the drive port it’s measuring positive 0.80v instead of -12v. I've tried two known working logic boards (the one in video is a Classic), both show 0.80v on pin 5.  On a different Classic II analog board both logic boards show -12v, so it's not a logic board issue.  I put the original CNY and TDA chips back in and still get 0.80v on pin 5, so ruling those chips out as an issue.
 
The picture output flickers and is very wobbly and the fan doesn't turn on (fan tested and works).  Otherwise it SEEMS to be working.
 
How do I trace the lack of -12v on the board?  Would the lack of -12v create a wobbly picture or impact the fan?  What other components or area of analog board should I be looking at to troubleshoot this?  I looked at the schematics but not fluent.  Has anyone experienced this issue before?  Thanks!
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Thanks for this suggestion. I swapped out the 79L12 and am still having the lack of -12v issue. I put the old 79L12 in a different machine and that machine is giving me -12v. So problem must be somewhere else.

 

I’m stumped. Hoping someone else here has seen this issue before.

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