Odd taillight issue

Discussion in 'Interior/Electronics' started by Ty20404, Jan 8, 2017.

  1. Ty20404

    Ty20404 Newbie

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    So I'm getting everything sorted out on my 78 hilux. My tail lights work fine (brake, signal and reverse) when the headlights aren't on but when I pull the switch to turn the headlights on, the brake lights become the turn signals and left and right are reversed, tail lights come on with reverse light. I'm fairly new to the hilux thing but if anyone could point me towards the most likely culprit I can start there. Curious if there is a module that controls these functions or if it's just the switch on the dash. Also I do get a faint flash from random bulbs that shouldn't be flashing both with headlights on and off. Thanks in advance. I'll be sure to post up what I find.
     
  2. jetas

    jetas Grand Toyotaholic

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    Theres a short or a bad ground
     
  3. fred heath

    fred heath Enthusiast

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    The headlight switch goes through the hazard flasher module before going out to the light bulbs. Do your hazard flashers work? It sounds like this would be a good area to start looking into.
    A good wiring diagram and voltage meter will be necessary for troubleshooting any electric circuits.
     
  4. Ty20404

    Ty20404 Newbie

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    I've got a Haynes manual. I didn't really see the flasher module on there but maybe I wasn't looking hard enough. Anyone have a picture of this module or where it is located? I would assume under the dash somewhere near the drivers side. Im guessing something is going on with grounding whenever the headlights are turned on. The flashers work fine with the headlights off but once headlights are on the rear lights are all reversed.
     
  5. jetas

    jetas Grand Toyotaholic

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    Flasher relay is bolted to the inside of the firewall right behind the radio
     

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