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Are the high and low headlight relays the same?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Galane, Dec 8, 2022.

  1. Galane

    Galane Junior Member

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    They're different colors, wondering if they're actually electrically identical? If they're the same I'll try swapping to see if the low works and the high doesn't.

    I really, really don't want to have to replace the light switch, thanks to whomever at Toyota thought it was a great idea to make it wrap around the steering column and require removing the steering wheel.

    It is extremely unlikely that both low filaments popped simultaneously since they're Silverstars just a few months old.

    NAPA, Autozone, O'Reilly, Advance Auto Parts - none of them sell headlight relays that fit 2nd gen Prius. I got the dim relay pulled out on a 2009 and noticed it has a connector pattern like a common "ice cube" relay but the main power terminals are much larger.
     
  2. Tombukt2

    Tombukt2 Senior Member

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    It's only a 10 minute job to change that combination switch with the wiper headlights rear wiper and all that It is a silly easy job 19 mm socket a torx bit undoes of the side wings of the center pad comes off undo a couple plugs undo the nut on the steering wheel but do not remove it undo the nut about four turns and then wiggle the steering wheel left to right while pulling up the steering wheel will pull up and hit the nut now undo the nut remove the steering wheel and set it on the seat If I'm not mistaken you'll need no tools to remove the combination switch assembly It just unclips from the clock spring and now clip the new combination switch on push the plugs through the holes in the steering wheel while putting the steering wheel back on straight just like you took it off because you haven't turned the shaft and everything should be spiffy with the torx bit in the 19mm socket sitting on the floor and your driver side by the time you sit in the car you should have the steering wheel off in about 12 minutes The rest is undoing plugs and swapping out the switch I've done it a bunch of times Good luck
     
  3. Galane

    Galane Junior Member

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    You didn't answer if the relays can be swapped. If they can and then the high beams don't work, that saves me doing the switch replacement. I've worked on cars since I was a wee lad. I know that few jobs ever go quick and easy when it's the first time a person does them, and when the car has never had the parts taken apart before.

     
  4. Tombukt2

    Tombukt2 Senior Member

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    I don't know I'd have to go out and pull them and look but I would say probably so One might be a slightly higher amperage rating for the high beams but I don't know I know a bunch of the relays will swap around If you look at the bottom pin outs and they look the same generally I would say so there's also diagrams on top of some of these things and all that kind of nonsense I have several cars here so I have several low beam and high beam relays at my access and to be clear so far I've never found either to be bad swapping them out moving them around I personally in the Gen 2 have never seen either of the headlight relays bad or burnt or with a hole in them or any of that. That doesn't mean they don't go bad but I have seen a lot of them since say 01 02 first Prii. In Corolla same I don't think I've seen a denso relay for headlights failed or burned so far in my travels ..bulbs yes burned.
     
  5. ChapmanF

    ChapmanF Senior Member

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    The H-LP relay is SPST and the DIM relay is SPDT. So no, they won't just interchange.

    If the only story is your low beams are out for some unknown reason, maybe just take the relays out and test them? If you find one faulty, there you go, and if not, you can just put them back and move on to next diagnostic steps.
     
  6. mr_guy_mann

    mr_guy_mann Senior Member

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    I have seen "new-ish" bulbs go out. Just saying. Might want to check one before getting into things too deep.

    Posted via the PriusChat mobile app.