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  1. #1
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    Default 12V doesn't equal 12V

    So I installed a power outlet on the dash and wired it directly to the battery (fused, of course) so I can use it to plug in a battery tender. Anyway, got to the end and continuity checked sat, but when I read voltage, it read 0 (it actually reads 3+ for a second and then drops to zero). So I checked power directly at the battery terminals and got the same reading. Turn the key and all power works fine. I don't get it. How can the battery read zero when I know it's putting out 12V?

  2. #2
    Very Active Member billybovine's Avatar
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    Quote Originally Posted by lbrty9 View Post
    So I installed a power outlet on the dash and wired it directly to the battery (fused, of course) so I can use it to plug in a battery tender. Anyway, got to the end and continuity checked sat, but when I read voltage, it read 0 (it actually reads 3+ for a second and then drops to zero). So I checked power directly at the battery terminals and got the same reading. Turn the key and all power works fine. I don't get it. How can the battery read zero when I know it's putting out 12V?
    Your meter is set to AC instead of DC

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  3. #3
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    nope, it's dry right. Only had one voltage spot which did ac and dc.

  4. #4
    Active Member jmbiii's Avatar
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    Where in Virginnie are you ?
    Close enough for some assistance ?
    Veni, vidi, discessit

    Potius sero quam nunquam

  5. #5
    Very Active Member Chupaca's Avatar
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    Default Hate to ask....

    Did you put in a fuse..?? could it be blown..?? did you go direct to the battery posts..??
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  6. #6
    Very Active Member spyderCodes's Avatar
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    I'm curious about your remark as to the continuity check.
    Could you tell us what that included?

  7. #7
    Active Member jmbiii's Avatar
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    Did you wire the power outlet directly to the battery ?
    When you measured at the battery, did you put the red meter lead on the positive (+) battery terminal and the black meter lead on the negative (-) ?

    There is no way you could see no voltage, then voltage if you measure directly across the battery. The switch only controls the power from the battery
    to connections after the switch.
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  8. #8
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    Quote Originally Posted by spyderCodes View Post
    I'm curious about your remark as to the continuity check.
    Could you tell us what that included?
    Checked resistance at the lead connection at the battery to the outlet. 0 Ohms on both wires. Continuity is good.

  9. #9
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    Quote Originally Posted by Chupaca View Post
    Did you put in a fuse..?? could it be blown..?? did you go direct to the battery posts..??
    Yes, it's fused. Fuse is good. Yes, I connected directly to the battery with the battery tender supplied leads.

  10. #10
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    Quote Originally Posted by jmbiii View Post
    Did you wire the power outlet directly to the battery ?
    When you measured at the battery, did you put the red meter lead on the positive (+) battery terminal and the black meter lead on the negative (-) ?

    There is no way you could see no voltage, then voltage if you measure directly across the battery. The switch only controls the power from the battery
    to connections after the switch.
    Yes, directly to the battery. Red was on positive, black on negative. And there is the reason for my question. Been working with electronics and electrical systems my whole life. This does not make any sense. Spyder is operating normally, I just can't figure out how I am reading 0 volts across a known good battery. I suppose my meter could be bad on the voltage setting, but it works fine for resistance. I'm going to go check it across my truck battery...

  11. #11
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    You guys were exactly right. Checked the battery on my Harley with the same results. There's only one voltage setting on the dial, but this meter has a function select switch that I didn't have set right. So it was on AC after all. I wouldn't have figured it out without that comment. Thanks!

  12. #12
    Very Active Member spyderCodes's Avatar
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    Quote Originally Posted by lbrty9 View Post
    Checked resistance at the lead connection at the battery to the outlet. 0 Ohms on both wires. Continuity is good.
    My bet is your meter is bad.
    My initial thought was you blew your meter out by checking resistance around the circuit that included the battery

  13. #13
    Active Member jmbiii's Avatar
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    lbrty9, excellent! So you can hook up your battery tender and the indicator light indicates it's charging ?

    BTW where in Va are you?
    Veni, vidi, discessit

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