Need 12V IGN or ACC wire in the engine bay

Discussion in 'Gen 3 Prius Technical Discussion' started by robby3, Jun 12, 2011.

  1. robby3

    robby3 Member

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    As the topic says, I do need a wire that is on 12V with IGN or ACC on. Our european cars do not have any DRL so there is no constant light on the fronts that I could use.

    Thanks in advance
    Rob
     
  2. spiderman

    spiderman wretched

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    Looked for that myself a couple of times with no luck. I ran a wire through the firewall. There might be a fuse in the fuse box that might provide that but I hate tapping that way.
     
  3. bzyrice

    bzyrice Active Member

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    On other cars I used the windshield wiper wires to tap into. Check those.
     
  4. seilerts

    seilerts Battery Curmudgeon

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    I've used the windshield washer pump wire on the Gen II and Sequoia. Works good, and there are almost no occasions where blowing the fuse would cause a driveability issue.
     
  5. robby3

    robby3 Member

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    Thanks for your replies. I have checked the washer pump but it has constant 12V and is activated by the relay. But this lead me to the idea to find another source there. And in fact on the top of the washer bottle there sits the headlight washer relais. One of its wires has IGN 12V and can be used for my puproses. Unfortunately, the front bumper must be removed to get access to the connector. Will post pics when I'm on there.
     
  6. bzyrice

    bzyrice Active Member

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    awesome.. i will need to know this power wire for something i have in mind later..
     
  7. dick_larimore

    dick_larimore Member

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    The easiest source of ignition ON power is to tap onto one of the legs of a fuse in the underhood fuse panel. The 10 amp IGCT #3 fuse is powered only when the ignition is ON. You can simply cut away the plastic surrounding one of the legs of the fuse at the top and solder a wire to the fuse. You can select one of the two legs of the fuse depending on whether you want the fuse to carry the current or not. The low clearance between the fuses in the panel and the fuse cover prevents using a plug-in fuse tap from being used.
     
  8. robby3

    robby3 Member

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    Thanks for your information, but no, I'd never do that. Even I'm an EE and I'm knowing what to do, I'd never tap into a fuse I don't know what else is feeded by this one.
     
  9. tonyrenier

    tonyrenier I grew up, but it's still red!

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    You can use the parking lights to tap into. It's well illustrated in the OEM fog lights PDF on Priusshop.
    Hope that helps.
     
  10. dick_larimore

    dick_larimore Member

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    Why not tap into a fuse? Every wire under the hood is being "fed" by something. Cutting into a wire is no different that pulling current off a fuse. I also am an EE.
     
  11. robby3

    robby3 Member

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    Unfortunately not. The parking lights only go on with the lights switch set to the first position. Having the Auto lights there is no power on any lights if ign is on and the lights not turned on (european car).

    A good source is at the plug on the top of the washer bottle. I'll use it when doing the DRL and horn mods.
     
  12. DRACO

    DRACO Member

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    Sorry to bring up this old thread, OP did you ever figure out where you could tap into 12V IG source?

    I am planning to install a HID kit but it requires I connect to the battery Posi side. The only place I can think of is the 100AMP fuse in the the dreaded fuse box.

    TIA,

    Jim
     
  13. xliderider

    xliderider Senior Member

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    Wow, you dug up an old thread. ;)

    If you need a 12v positive, always on, point, then there are two open terminals at the back of the engine fuse box. Seen in this picture with the red wires connected:

    [​IMG]

    Treat them like the positive terminal on the battery.

    If you want a 12v ignition switched power source, then you can tap one of the fuses in the fuse box that's powered only when in Ready Mode.
     
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  14. xliderider

    xliderider Senior Member

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  15. DRACO

    DRACO Member

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    Lucky me, my MIL's Gen 1 is barried under the fuse box on the 100AMP fuse

    [​IMG]

    Thank you XlideRider

    and as an BONUS, Gen1 is Bi-Xenon ( H4B2 ) system, oh the Joy :D