HID Kit wiring harness necessity?

Discussion in 'Gen III 2010+ Prius Accessories and Modifications' started by vegeto626, Jan 1, 2012.

  1. vegeto626

    vegeto626 New Member

    Dec 22, 2011
    Orange County, CA
    2011 Prius
    Hi everyone, I will be getting the DDM HID kit and wondering about the necessity for a wiring harness as it seems many of you are running without it. I am concerned the not having it will somehow damage the car (based on researching HID's in general) but loving the plug and play idea of running without one. Just wondering everyone's thoughts.

    Also where are the positive and negative leads in the hood the harness should plug into? (pics? Sorry currently on phone)

  2. GaR619

    GaR619 Junior Member

    Nov 30, 2011
    san diego
    2013 Prius
    I bought the 5000K H11 kit with slim ballst. No wiring harness. everything was just plug in. took about 30 minutes to isntall.
  3. gohybrid

    gohybrid Junior Member

    Oct 25, 2009
    2010 Prius
    The question I would ask is "why not use the harness?" Sure, it's a little extra work to install and dress properly, but in the end, if *anything* goes wrong on the wiring end, it's all in a place where you can get to it and replace or repair without having to investigate and extract factory wire runs. It's cheap insurance.

    Another thing to consider is that the power supply characteristics of this particular ballast are likely not documented or thoroughly known. It is entirely possible a current spike of a sufficiently short duration could fail to blow a fuse, yet still damage a semiconductor. It's a little more of a long shot, and I don't know enough about the Prius' headlight circuit to know if that's a danger or not, but again - why take the chance?

    To answer your question, the terminal i've seen people use for positive supply is in the fuse box under a small cover. You'll install a ring terminal on top of the existing lug. Ground can really come from any metal you can bolt to, but I've personally seen a dedicated ground terminal on the drivers side just outboard of the headlight, about bumper level. The advantage of using that location is that you can minimize the ground potentials between your ballasts and the true ground. Ground loops are ugly things.