What are the voltages for each USB 3.0 header pin of Aspire ATC-710-EB51

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Answers

  • Larryodie
    Larryodie Member Posts: 1,680 Community Aficionado WiFi Icon

    Please post snips of the circiuits t hat low ohm caps are in, and post the size & nomenclature.

    DId you check the fuses in the Meter as you'll get funny ohm readings of they are blowing.

  • SafeandSound
    SafeandSound Member Posts: 64 Troubleshooter
    edited November 21

    The caps circled in black, blue, purple and cyan are the ones with low resistances. Here is a photo for reference:

    image.png

    The caps circled in blue are labeled EC14, EC15, EC12 (below the CPU, right to left) and EC17 and EC18 (left of CPU, bottom to top). They have the same resistances, measured at 3.5 ohms, and they are in the same circuit according to the schematic, which is on page 39. Here is an image of the page of the schematic:

    image.png

    The cap circled in cyan is EC16 and has a resistance of 21.7 ohms. The caps circled in purple are EC21, EC22 and EC23 (bottom to top) and they have a resistance of 11 ohms. The schematics for these capacitors are all on page 40, here is a copy:

    image.png

    And finally there is the capacitor in black which we were discussing before, labeled as EC34 with a resistance of 1.5 ohms. Here is a copy of the schematic, located on page 44:

    image.png

    I couldn’t find the IC chip for U35, although I did find the marking in the motherboard. Do you think it has anything to do with the resistors next to it?

    image.jpg

  • Larryodie
    Larryodie Member Posts: 1,680 Community Aficionado WiFi Icon
    edited November 21

    DID you check the fuses in your meter or double check with another meter ????

    The chip is a UP1537. AS I SAID BEFORE LIFT PIN 8 to verify. You're running circles as I'm typing needless, CHECK YOUR METER FUSES then lift pin 8 or cut the pattern to pin 8.

    All those caps mentioned or in parallel so you're going to start removing feeds to isolate, probably using an Exacto knife to cut patterns or solder suck/solder wick each one BUT CHECK THE FUSES IN YOUR METER use another meter to verify. Blown meter fuses will cause low reading.

    image.png

  • SafeandSound
    SafeandSound Member Posts: 64 Troubleshooter

    My multimeter only has one fuse as far as I can tell and it’s not blown. Here’s a photo of it:

    IMG_0523.jpeg

    I don’t have another multimeter to verify the readings this one is giving for resistance, but I measured the resistance of my finger, switching the range to 20M ohms and it bounced around a few million ohms, so I don’t think it’s giving low readings:

    image.jpg

    I believe I also found the chip that is U35. There are two ICs on the motherboard that have UP1537 written on them and the other one has U22 written next to it, here’s a photo of it:

    IMG_0526.jpeg

    but which pin is pin 8?

  • Larryodie
    Larryodie Member Posts: 1,680 Community Aficionado WiFi Icon

    Great, as I was going to suggest that you measures your body resistance. The meter pdf that I posted had 2 ceramic fuses.

    NOW troubleshoot as why the CAP in black shows low ohmage, you'll have to physically trace the land patterns from it (using your snippets of that circuit), it looks like that it feeds pin 8 of U35.

    So lift pin 8 or xacto cut the pattern to pin 8 and see if your short across the black cap disappears.

    It is all elementary trouble shooting from here, just start eliminating the parallel circuits to the BLACK CAP

    Follow the positive lead from the black cap to U35 pin 8 and lift or cut to see if the short disappears as I'm betting on a corrupt U35 from a power surge or static electricity arc.

    The dots and arrows on U35 will give you pin 1 location. Looks like pin 1 is with the arrow but not always true. As I said trace the pattern from the + on the black cp to the IC

    GOOD LUCK, I'm out of here for good as I have some medical problems that require less stress and more rest.

    Remember that you still have the USB problems and the computer is OLD.

    Do you self a favor and trash it, no used MB, just buy new and enjoy the speed and WIN 11'S technology.

  • billsey
    billsey ACE Posts: 34,219 Trailblazer

    I really have to step in to say trying to measure resistance on a capacitor is a gesture in futility. Here is how Fluke suggests they be measured. What you are doing is measuring resistance through the circuit board and that will be radically different at different places in the circuit. You would have to pull the capacitor off the board to measure it without the rest of the circuit throwing the numbers off. Your multimeter should be on the capacitance position on the dial switch, not on resistance.

    Click on "Like" if you find my answer useful or click on "Yes" if it answers your question.
  • Larryodie
    Larryodie Member Posts: 1,680 Community Aficionado WiFi Icon
    edited November 21

    Deleted by me.

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