LED Daytime Running Lights

Discussion in 'Gen 3 Prius Technical Discussion' started by WinstonTheodore, Mar 25, 2012.

  1. WinstonTheodore

    WinstonTheodore New Member

    Joined:
    May 29, 2011
    11
    0
    0
    OC, California
    Vehicle:
    2010 Prius
    Model:
    II
    Does anyone know why the DRL's turn off when the headlights turn on? Is there anyway to make it so they stay on at the same time as the headlights? I noticed that the Audi's, etc. all stay on during night driving with the headlights so i'm unsure why my 2012 doesn't.
     
  2. KK6PD

    KK6PD _ . _ . / _ _ . _

    Joined:
    Mar 24, 2008
    3,885
    803
    115
    Los Angeles
    Vehicle:
    2014 Nissan LEAF
    You don't really need DRL's when on when the headlights are on. I would assume it's a power saving thing! You can always get a copy of the electrical schematic, find out where the relay is that controls DRL's and modify it to your needs! Sounds like a lot of work, but it is probably not that bad. If I had a copy I would point it out and send it to you. I run a Gen II, so I never got Gen III prints!
     
    1 person likes this.
  3. 32kcolors

    32kcolors Senior Member

    Joined:
    Jul 14, 2009
    5,728
    937
    124
    Redondo Beach, CA
    Vehicle:
    2010 Prius
    Model:
    V
    Probably a carryover from Canadian and European laws prohibiting DRLs while headlights are on.

    You're in California and can have up to 4 lamps lighted at any one time, so maybe do a mod to have them stay on at all time.
     
    1 person likes this.
  4. sw20td06

    sw20td06 Junior Member

    Joined:
    May 2, 2012
    15
    0
    0
    California
    Vehicle:
    2012 Prius
    Model:
    Three
    I would like to now the same thing too. I have a 2012 and the LED's would look great on with my low beam HID. If anyone figures out a simple mod to do this that would be great.
     
  5. Cvk14

    Cvk14 Junior Member

    Joined:
    Apr 16, 2012
    37
    4
    1
    New York, NY
    Vehicle:
    2012 Prius
    Model:
    Three
    There must be a way to get a tap off of the switch to the ECU and have it also switch on the DRL. I'd love to do this as well.
     
  6. pauln64

    pauln64 Junior Member

    Joined:
    Nov 16, 2011
    77
    8
    0
    Macon, GA
    Vehicle:
    2012 Prius
    Model:
    Two
    It would be nice. But if taking the literal version of it, DRL is for during the daytime only. Once you have the headlights on, DRL is no longer needed. Although it would be nice if they just put the LED's in the headlights and use the "dots" running across the headlights. I think someone here had done this mod before.
     
  7. PaJa

    PaJa Senior member

    Joined:
    Sep 3, 2009
    677
    111
    92
    Czech republic
    Vehicle:
    2010 Prius
    Model:
    N/A
    On EU market the switching DRL off when head lights on is a must due to the UN/ECE directive. But it is not followed by all automakers, f.e. Audi, Skoda and etc. There is a document for the reference purposes link, DRL specification is in 6.19 paragraph.
     
  8. jerrydelrey

    jerrydelrey Junior Member

    Joined:
    Nov 26, 2011
    92
    6
    0
    Honolulu Hawaii
    Vehicle:
    2010 Prius
    Model:
    IV
    Yeah I really wish Toyota put LED's in those dots.
     
  9. pauln64

    pauln64 Junior Member

    Joined:
    Nov 16, 2011
    77
    8
    0
    Macon, GA
    Vehicle:
    2012 Prius
    Model:
    Two
    on a side note...notice only 4 LEDs lights and it looks like there's a fifth LED that is not on? If I have time, I'm going under the car and take a close look at the DRLs
     
  10. fuzzy1

    fuzzy1 Senior Member

    Joined:
    Feb 26, 2009
    8,802
    2,549
    85
    Western Washington
    Vehicle:
    2012 Prius
    Model:
    Three
    The 2012 still has the same nonfunctional decorative dots as your 2010. But I was pleasantly surprised to find real LED DRL's on the 2012, mounted where the fog light knockouts were placed on the 2010.

    Look closer from the front. It has 6 lenses, one of which is partially obscured. But look really close, only the top 4 lenses have LEDs (yellowish component) behind them. The bottom 2 show only white plastic, no LEDs.

    Electrically, I bet these are driven as two in a series string, with two paralleled strings. A single fifth LED would not fit the driver pattern
     
  11. scooter4n

    scooter4n Junior Member

    Joined:
    Mar 3, 2012
    27
    14
    0
    USA
    Vehicle:
    2012 Prius
    Model:
    Three
    I was looking in to doing that for few months, here is what I found:
    DRL relay is under the hood marked DRL, I was going to jump relay coil from head lights to turn relay ON when headlight are one, but NO NO, when headlights are ON all power to that relay is OFF even HOT leg, so even if you turn relay coil ON there still no power to that relay to send i to the lights.
    I dont know why Toyota made it complete shut off, but it has something to do with headlights relay and that relay no where to be found, at list under the hood.

    Did I clear the mud a little? :)
     
    1 person likes this.
  12. mad-dog-one

    mad-dog-one Prius Enthusiast

    Joined:
    Dec 31, 2009
    1,147
    365
    0
    Whereabouts Unknown
    Vehicle:
    2010 Prius
    Model:
    V
    I didn't know we were limited to 4 lights on at a time in California. I suppose that prevents single car parades from blinding other drivers. This must crimp the style of overpaid athletes and gangster celebrities.
     
  13. sw20td06

    sw20td06 Junior Member

    Joined:
    May 2, 2012
    15
    0
    0
    California
    Vehicle:
    2012 Prius
    Model:
    Three
    I didn't know the light rule either.
     
  14. ES44AC

    ES44AC C.A.U.S

    Joined:
    May 7, 2012
    225
    33
    0
    USA
    Vehicle:
    2011 Prius
    Model:
    One
    I removed my posting as the information I gave wasn't applicable to the question asked. Sorry for the confusion! :D
     
  15. sun4i

    sun4i Junior Member

    Joined:
    Oct 21, 2008
    14
    0
    0
    Costa Mesa CA
    Vehicle:
    2012 Prius
    Model:
    Three
    Has anyone figured out how to do this mod?
     
  16. markabele

    markabele Senior Member

    Joined:
    Mar 27, 2012
    3,720
    867
    1
    Nebraska
    Vehicle:
    2013 Prius Plug-in
    Model:
    Plug-in Base
    I've always wondered why there is a switch for the DRL's on the blinker stalk and then also a thing on the settings screen about turning DRL's on or off.
     
  17. pghjerry

    pghjerry Junior Member

    Joined:
    May 20, 2012
    58
    20
    0
    Dodge City, KS, USA
    Vehicle:
    2015 Prius c
    Model:
    Four
    I agree completely...Ive tried turning the setting on and off on the radio and it makes no difference, you can override it with the switch on the blinker.