SM74 Ink Keys Show As Wide Open

Discussion in 'Heidelberg Printing Presses' started by memphisvol, Nov 15, 2021.

  1. memphisvol

    memphisvol New Member

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    I'm having an issue with our 1999 SM74...we periodically have a problem where the ink keys show 100% wide open on every unit on the console, but are not actually wide open.

    If you try to lower them back down on the console, it errors out every key. We had this problem a year or so ago, but I cannot for the life of me remember what I did to get it to go away. We are pretty much down on that press until I can come up with a solution though, so any input/ideas are appreciated.
     
  2. junker1984

    junker1984 Senior Member

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    I would suggest you first reset all circuit boards in the CPC unit. Remove cover to expose all boards and simply unplug and plug back in. You mayb ant to remove each one completely (one at a time!) and spray with electronic cleaner. There are boards in the rack that would have nothing to do with the issue you’re having, but it surely won’t hurt anything to do them all.
     
    turbotom1052 and asem alsafady like this.
  3. memphisvol

    memphisvol New Member

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    I forgot to put in the original post that I had already reset all of them...I sprayed each out with electronic cleaner for added measure.

    Just wanted to let anyone else who googled this problem know, I fixed it by freeing up and rotating the 15ish fuses on the back bottom wall of the console behind the NTK boards. Apparently over the years they tend to "rust" (not really rust) into place which makes the electronics do weird things. Rotate each one of them and then bam, we're back up and running. Go figure.
     
  4. SebastienVaudry

    SebastienVaudry New Member

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    wow, good news
     

  5. Thirumalaikumar

    Thirumalaikumar Member

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    check the tw0 18V from transformer and check the white and red connectors may be its a bad connection of 18 v or filter board SFK is faulty
     
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