Acer Nitro AN517-52 FH51M LA-J871P Works on battery only. Won't charge.

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  • mon2
    Badcaps Legend
    • Dec 2019
    • 14246
    • Canada

    #21
    Review the middle black resistor that is near the bottom side of pub1 in the picture.

    Markings are 000. Is this resistor with a solder blob across the pin to the part on the right side? Appears to be with a hunk of solder.

    Comment

    • gadgettree
      Member
      • Feb 2022
      • 15
      • Canada

      #22
      You have a keen eye, I missed that. Yes those two components were bridged at the top there. I have removed the bridge with wick and flux.
      Laptop still does not turn on or charge. Would that bridge have damaged the charging ic?

      Comment

      • madjid911
        Badcaps Veteran
        • Dec 2016
        • 390
        • France

        #23
        Hello, I had exactly the same problem as you, everything was good resistance and voltage (ACDET 2V6, REGN 6V, VCC 20v, ACOK 3V3) but no 20v at the pqb3 and pqb4 output, thanks to you I was able to check everything and repair the laptop, for my part, I had a short on a capacitor, once replaced I had the 20v but the mosfets did not close, after seeing this post, I checked everything like you, I had PB24 poorly soldered (because I had replaced it), there was missing solder on pin 3, after having resoldered it, the laptop loads and turns on correctly.

        From what I see in your photo of BQ24, you have the same problem as me, it looks like, looked at your pin 3, it is missing some soldering​

        Comment

        • mon2
          Badcaps Legend
          • Dec 2019
          • 14246
          • Canada

          #24
          Agree with the last post and adding another area to review for possible shorts. Best to flux each area and hot air them. This should allow for the solder to flow into place. If required, use desolder braid to remove the excess solder.

          Click image for larger version

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