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LaserWriter IINT flashing 2 red lights, after replacing AC and DC boards

I’ve been trying to get this LaserWriter to work for months. Last year it worked fine and I was able to print things out on it then it gave me a flashing red light on the two sensors that indicates an error with the AC block, so I recapped the capacitors that were in the Board that had the fan on it that didn’t seem to fix it. I tried replacing the other board, I believe that’s the DC board that didn’t fix it so I don’t know what else to do with this printer. Apparently the error is linked to a fuser error according to the manual. anybody had luck with trying anything else?
 
You may want to read through my thread on when I fixed this exact issue with my LaserWriter II.

Essentially, I replaced both C702 (a 10uF 50v capacitor) as well as the triac on that board. I replaced it with a Q6015L5TP and it worked great after doing that. I have seen other people say that sometimes the optoisolator on that board can go bad, but at the time I couldn't find a direct replacement or NOS part for it (it's a S21ME4 Sharp X7) so I left that and for me, it clearly wasn't bad as mine still works.

You're right that this could indicate a fuser issue. Well, this actually is a fuser issue - it means that the fuser can't heat up, but that is usually caused by the PSU these days, but it could actually be a dead fuser. If you read through the service manual, there's a process for measuring the resistance of the fuser to see if it's bad or not. I'd recommend following that and seeing if you have a bad fuser before doing any more work on the PSU.
 
Thanks for the response. Well it turned out when I took out the fuser assembly and put it back in it printed a test page again. Probably wasnt seated in correctly I guess recapping that little ac board fixed it
 
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