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3rd Brake Light Wiring/Plug

Discussion in 'Gen 3 Prius Care, Maintenance & Troubleshooting' started by cb1ocker, Jan 3, 2017.

  1. cb1ocker

    cb1ocker Junior Member

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    2016 Prius
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    Three Touring
    The 3rd brake light on my 2011 Prius stopped working recently, so after reading many posts on this forum and elsewhere I ordered a brake light and installed it. When I swapped in the new one I was only getting very faint light with the brake depressed. I tested the connection and found that I was only getting between 3 and 6 volts at the plug, depending on how I wiggled the probes..

    As soon as I started looking closer at the plug I noticed a ton of corrosion, presumably caused by driving it around for however long with the old cracked enclosure. As I was using a small pick to clean the corrosion out of the plug, the metal strips that make the connection on the positive side of the plug fell out. Now I'm getting 0 volts at the plug.

    I've been trying to find a replacement plug/connector/wire/anything that I could install in it's place, but I'm having no luck. Does anyone know where I can find this plug, or something I could rip it off of? I know there isn't a lot of wire to play with there, but I'm confident I could solder in a replacement if I could just find the right piece.

    [​IMG]

    [​IMG]
     
  2. cb1ocker

    cb1ocker Junior Member

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    Barring a miracle of someone actually knowing where I can get replacement plug or wiring for cheap, I think I may resort to cutting the connector off and soldering on some small press fit/quick connects to the positive and negative side of the wire, then run those to the light. As long as I can get a solid connection at the light without soldering, it should still allow for the light to be swapped out again in the future if necessary.

    As far as safety for cutting this wire, as long as I'm not pressing on the brake pedal while I'm working, this should have 0 volts coming to it, correct? I'm trying to avoid having to disconnect the 12v battery if possible since I'm assuming disconnecting it will revert everything electrical back to defaults, but maybe I'm wrong on that.
     
  3. ChapmanF

    ChapmanF Senior Member

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    You're in luck, there's no miracle involved at all. You look in the wiring diagram online at techinfo.toyota.com and find your connector. You can follow along in this post to see how. (That one is looking for the rain sensor connector in a Gen 4, but it'll show how you search.)

    As you can see, when you pull up the info on the connector, it has the part number (of the plastic connector shell). While I didn't show it in that example, you also see a line there saying "[+] Wire Harness Repair". You click the + and it expands to show you also the part numbers for the replacement metal terminals that go in it. You take those part numbers to your friendly local Toyota dealer (or to any of the Toyota dealer web sites online), and walk away with the parts (or have them delivered to your door).

    The way Toyota sells those repair terminals, they have a few inches of wire already attached, so it doesn't matter if you lose some length cutting back to good wire from your old ruined connector. You just attach the wires to the new terminals, pop them into the connector shell, and you're good to go.

    Edit: I should mention that when you "pop them into the connector shell", there are generally two features built into the shell to hold them in place, one of which just clicks when you push them in, but one you have to know how to release and reclamp. An early section in the wiring diagram explains that (and the mechanism will be shown in the picture of your actual connector).

    -Chap
     
    #3 ChapmanF, Jan 4, 2017
    Last edited: Jan 4, 2017
    Rebound likes this.
  4. cb1ocker

    cb1ocker Junior Member

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    Three Touring
    That is awesome. I spent all day looking for a diagram like that and Google failed me entirely. I also checked for a pinned post somewhere on Priuschat that might direct me, but came up short there as well. Entirely possible I just missed it though. Thanks much for this information!
     
  5. cb1ocker

    cb1ocker Junior Member

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    On second thought, I'm not too keen on paying $15 for a 2 day subscription to get the part number. I think I may just go with my plan b, I can do that with parts I already own :)
     
  6. Rebound

    Rebound Senior Member

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    Most guys at the Toyota parts counters will pull those up and print them out.
     
  7. cb1ocker

    cb1ocker Junior Member

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    That is good to know, thank you. I've bookmarked the TIS site for future reference, I can see that coming in handy and being totally worth it the next time I need to tackle a major repair.