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Help finding L7 Connector for Auto Headlights

Discussion in 'Gen 3 Prius Accessories and Modifications' started by Flaninacupboard, Jun 13, 2010.

  1. cproaudio

    cproaudio Speedlock Overrider

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    The part number you've given for the Canadian stalk is 84140-07141 When I went to the dealer and ask them which vehicle does 84140-07141 stalk belong to. I was told that it is listed for Rav4, Tundra, Camry, Avalon, Venza, 4Runner of current generation. The parts dept wanted me to provide VIN number in order for them to order it. Toyota's known for using same parts for multiple models. They even share some parts with Lexus and Scion. It's not that hard to tell if the stalk look the same as the our Prius. I look my parents GenII Sienna (2006) and I can tell right away that it won't work. The 2011 Sienna on the other hand use the same style stalk as the Prius.
    Here's another example DIY - Liftback Intermittent Wipers via Stalk Replacement (v2.0) - Toyota Yaris Forums - Ultimate Yaris Enthusiast Site Some Yaris owners are using Prius, Rav4, Highlander, RX330, RX400h wiper stalk to add intermittent rear wipers.

    The plug should be the same except the missing wires that correspond to the OEM stalk's missing functions. You wrote that a wire is missing from pin 19 of the L47 headlight stalk connector. That's the wire for the auto headlight function. That's a good example of that. All I'm saying is that he should hunt the dealer lot for a stalk that fit his bill and order the stalk for that vehicle. For the US stalks, Toyota will have different part numbers for stalks that states "Off" and "Off/DRL" But both stalks function exactly the same. Both stalks are interchangeable. There might be a wire for the Off/DRL position to activate the DRL but that's it. Cars without DRL can still use a stalk that has "Off/DRL" There's no extra wire for the DRL since the car doesn't have DRL. That same thread also lists 2 different stalks with different prints. Both stalks function the same are interchangeable.
     
  2. sdetweil

    sdetweil New Member

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    well, I am all ready to do this auto headlight setup AND fog lights.. I have installed the fogs, and the stock canadian light stalk.. time to scavenge the pins and go to town..

    well, there is no L8 hanging out, or L66 either..
    this is a II trim..

    the wire to add in the ECU for the fog light switch also doesn't turn on with the headlight stalk.. SO I assume there are wires in the L47 connector missing.. (there are 3 new pins across the top row of L47)
    (in addition to the pin 19 for the headlights.)

    anyone saved the wiring diagrams from TIS I can peruse?

    this also leads me to believe that the light sensor isn't one.. we do experience one weird lighting effect. turn on the headlights, any time of day, and the dash lights dim.. even in bright sunlight.. SO, my guess is that it is NOT a sensor on the II.

    if u have the pdfs from TIS and are willing to share, send an emial to my userid at gmail.com

    Sam
     
  3. jayvee

    jayvee Member

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    The display dimming when you turn on the headlights is normal. If you turn the dimmer switch all the way up past the "click", then the display will stay at full "headlights off" brightness.

    The wiring diagrams for stalk wiring make no distinction between versions II, III, IV, or V. (Sorry, I can't share them - they are copyrighted.) There are some differences with the V, having to do only with LED headlights - but no differences in the stalk to ECU wiring. However, that doesn't mean they populated all of the wires in the harnesses for all models. I don't know about the II. (Anyone done this mod on a II?)

    For the fogs:
    You should have a lavender wire coming out of pin 3, and a light green wire coming out of pin 4, of L47. These are the ground and high side connections, respectively, for the fog switch. The pin 4 wire should go to pin 27 on L7 at the ECU. (The pin 3 wire just goes to a ground junction, so you can connect this pin to any ground if the wire is missing.)
    I'm also assuming you wired the +12V for the fog lights themselves from the ECU (it's actually a junction/relay box) "2C" connector, Pin 8, through the firewall to the fogs. You must add this wire to use the factory relay for the fogs. (Or are you bypassing the factory fog relay and using your own?) It's possible that your II may not have the fog relay in your ECU - but it's easy to check. Once you have pins 3 and 4 wired as described above, turn on the headlights (not just parking lights). Then turn on the stalk fog switch - - You should hear a small "click" come from the ECU. If you hear the click, you do have the relay in the ECU. (This also assumes the 12V battery in the back is re-connected, obviously...)


    Auto Headlights:
    It appears that you may not have wired the light sensor's pin 4 to ECU L7 pin 21 as required (and I'm quite sure you do have a sensor - it is also used for A/C control on all Gen 3's) - the fact that you're not sure if you have a sensor leads me to believe you haven't wired it. ;) If you haven't, the Auto Headlights definitely will not work. Wiring this pin on the sensor is not easy, but folks have done it without removing the entire dash. (I chose to remove the dash...)
     
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  4. sdetweil

    sdetweil New Member

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    sure, but thats just dumb.. having to adjust the dash brightness everytime the lights come on in marginal lighting.

    thanks.. that is exactly what I was looking for.
    there are no wires in the L47 connector for pins 2-4 (1 has no pin in the switch)

    you said 4 is the 'high side', but I think you meant it is whatever pin 3 supplies when the switch is closed.
    the switch closes pin 3 & 4. I tested 2, 3, & 4 for ground when the switch was on, and of course didn't find it!.

    so, another way to test for the relay is to ground L7 27 and the relay should click. right? otherwise I'll have to use the fog harness supplied relays.. no big deal.

    correct, I wanted to wire up the Pin 8 to power the fogs directly, and was checking that pin before running the wire to the engine bay.
    I was surprised not to find power there at all.. I didn't hear or feel the click either.. but lacking L47 3&4 would explain it!

    right, haven't wired the pin 4 yet, and I was going to try the remote reach approach, but the lack of the pins to scavenge gave me pause. the light relay is turned off when going from lights on to auto on the stalk, so that means at least the technical logic is present in the ECU.

    and Man these wires are tiny!!

    I can't see pin 8 supporting enough current long term for the fogs..

    Sam
     
  5. jayvee

    jayvee Member

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    The dealer (or someone with Techstream and an interface) can adjust the sensor sensitivity and "trip point" somewhat between full brightness and dimmed (see manual page 589 and 591) - but it simply goes to the dim level that's set on the dial.


    Correct. It's the high side because this is a control line that is probably at +5 or +12V (through a pullup resistor) until it is grounded. Until it is connected to ground, it's floating at +5 or +12V. (high)

    Correct.

    You can go to the dealer and order pins with 6" of wire attached - they just need to look up the schematic and that will give them the pin replacement part number - but they are expensive, often over $10 per pin.

    You'd be surprised. The circuit is fused at 15A, and Toyota seems to usually pretty conservative about wire and pin gauges. I've had mine wired for over a year with basically constant nighttime use (I leave my fog switch on all the time, because I like the side illumination it provides, even in clear weather) and have seen no indication of heat stress or damage. The hardest part was getting a 14 gauge +12V wire attached to the scavenged mating pin and still have it go into the 2C connector. Not easy.
     
  6. sdetweil

    sdetweil New Member

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    And another way to handle this without dragging power thru the firewall, (assuming you are using the Priuschat add on fogs with separate relay like me) is to take the #4 wire out thru the dash to the ground trigger lead of the relay. (which is what the manual switch provided in the fog light kit does)..

    so instead of triggering the ECU relay you are triggering the engine bay fog relay. when the lights are on, etc..

    and then u don't need the heavier gauge wire as you are just feeding float or ground.

    hm.. this will depend on how the fog switch actually works. If its mechanical, then it would just turn the fogs on all the time.
    If its dependent on the headlight switch position, then maybe it would work direct.
    If its mechanical then we would need to depend on the ECU programming.
    No time to test til Sunday

    Sam
     
  7. adrianblack

    adrianblack Member

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    Hmm, I have documentation showing the light sensor pin 3 going to L7-20 and pin 6 going to L7-22. (And pin 1 goes to A/C amp...)

    EDIT: Nevermind, I see L7-20 and L7-22 are always connected, L7-21 <-> Pin 4 needs to be added as well.

    I haven't looked on my III, but are all Priuses without auto highlights missing the sensor wiring?
     
  8. sdetweil

    sdetweil New Member

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    Yes, it appears that no US model has auto headlights, and no wire at pin 4.

    Canadian vehicles DO have auto headlights.

    Sam
     
  9. sdetweil

    sdetweil New Member

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    Well, I made it part way today.. the wires in L47 for both the headlight and the fog light. the 3/4 wires are just mechanical,
    so you would have to have a relay powered by the headlights for the fog lights, or wire up to L7 as noted above.

    now, gotta find some pins for L7..

    Need 4.. 2 for the headlights and 2 for the fog lights
    one in the 2C pin 8 spot

    Sam