HP F4180 stopped working please help troubleshoot

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • flat-earther
    Senior Member
    • Dec 2022
    • 124
    • palestine

    #21
    I removed the three electrolytic caps on the print head board and they measure good.

    Comment

    • flat-earther
      Senior Member
      • Dec 2022
      • 124
      • palestine

      #22
      I reassembled the printer, it was difficult because it has been months since I disassembled it so I didn't remember how to assemble it but I got it done and this disassembly video helped me https://www.youtube.com/watch?v=hgiCGBt-C3U

      Those ribbon cables are a nightmare, they are so thin and you have to push them in which makes them buckle, very bad design. I put silicone spray on one of them to try and make it go in easier.
      I sanded the cable and the plastic tab that fell off of two of them and superglued it back on.

      I powered up the printer and guess what, same error as before.

      Out of curiosity I measured the output(emitter pin) of the 16V NPN BJT while powering the printer up now that it's assembled, and it gradually went to -0.12V, what does that mean? I wonder why it went negative. at no point did it have 16V.
      Attached Files

      Comment

      • flat-earther
        Senior Member
        • Dec 2022
        • 124
        • palestine

        #23
        I removed the cover on the IC that's on the print head PCB, here's photos
        74C9TNTG4
        SN105117BPZP
        1525-0036
        Attached Files

        Comment

        • flat-earther
          Senior Member
          • Dec 2022
          • 124
          • palestine

          #24
          New video in which the printer is fully assembled apart from the top part lifted away which is sitting aside (but with all cables connected) so I can see inside the printer.
          I show with a thermal camera what it looks like when powering up the printer.
          Can you see anything peculiar?
          https://rumble.com/v6ye2uu-faulty-hp...mera-view.html

          Comment

          • flat-earther
            Senior Member
            • Dec 2022
            • 124
            • palestine

            #25
            As seen with the thermal camera the Texas Instruments SN104961PJP is heating up.
            I hope that's not the problem because it's a custom chip.
            Attached Files

            Comment

            • flat-earther
              Senior Member
              • Dec 2022
              • 124
              • palestine

              #26
              at time 1:50 in the video I see the voltage regulator EH11A 652J84 is heating up.
              Attached Files

              Comment

              • flat-earther
                Senior Member
                • Dec 2022
                • 124
                • palestine

                #27
                at 1:26 in the video there is another chip getting hot.
                I don't know right now what that chip is as it's inaccessible without removing the motherboard and my old photos I posted here on badcaps of the motherboard are gone, actually all the photos I posted on this forum around may and june 2025 are gone.
                Attached Files

                Comment

                Related Topics

                Collapse

                Working...