RJ45 CAT open circuit

Discussion in 'Home Automation' started by AndyPRK, 6 Dec 2018.

  1. AndyPRK

    AndyPRK

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    hi. I have installed a cable between my upstairs Panasonic tv and router.

    I have crimped the ends myself.
    It doesn’t work!!!

    Neither light is on, on the router.

    When I plug my downstairs tv I’m using purchased cable it works and the 2 router connector lights come on.

    Apart from buzzing out every wire are there any voltage measurements I can make to see which wire is open. ?

    I have wired it straight through.

    Are all 8 wires required or can I focus on less?

    It’s proper Cat 5 cable

    Thanks
     
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  3. AndyPRK

    AndyPRK

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    Sorted. Will say how later.
     
  4. rsgaz

    rsgaz

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    Oooh, shall we guess what was wrong?

    Had one plug upside down when you put the wires in? So pins 1 to 8 was wired 8 to 1?
     
  5. AndyPRK

    AndyPRK

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    Nope

    Want to get my floor boards down
     
  6. AndyPRK

    AndyPRK

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    I measured the voltages coming out of the working TV.
    Couldn't see anything interesting or useful.

    I disconnected both ends of the faulty cable, and used the crimp tool to short all the pins together.

    I continuity checked the other end, to ensure all wires were connected. They were. :(

    I then moved the short to the other end of the cable and tested at the other end. (incase the crimp tool was helping keep the pins pressed in)

    I noticed pins 3&4 I think had a poor connection or open circuit. (TV end)
    When I had a closer inspection, I noticed these pins were raised when compared to the others.
    Some of the pins weren't pressed fully home. I pressed them in with a screwdriver.
    I then got the crimps and re crimped it. I noticed you have to be careful to watch the crimp to ensure it lined up with the pins correctly.

    Tested it and it now works.

    That's what you get for using a £3 crimp tool. But at least I know to watch them IF I used them in future.
     
    Last edited: 6 Dec 2018
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  8. motorbiking

    motorbiking

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    You can get test kits on ebay for about £3. Its worth it, if you are doing a few.
     
  9. AndyPRK

    AndyPRK

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    Don't intend doing any more so not worth having test kit.

    I did put a 2nd cable in to another bedroom as the floor boards were up anyway.
    I don't intend using it and will watch carefully when I apply the crimps
     
  10. AndyPRK

    AndyPRK

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  11. AndyPRK

    AndyPRK

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    Only pins 1,2,3,6 used for most applications.


    If computer to computer it is different.
     
  12. DIYnot Local

    DIYnot Local

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