led tail light havoc

Discussion in 'Audio + Electronics' started by Childs, Jul 23, 2020.

  1. Childs

    Childs Newbie

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    I just installed led tail lights and they caused my ignition lights to go out and my truck won't start. 95 k1500 5.7. All fuses good. Engine will turn over. Only seatbelt light is coming on in cluster. Any ideas? I'm about to go remove the new lights and see if that works. I did try reconnecting the battery. Ecm won't put out codes either.
     
  2. Childs

    Childs Newbie

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    Putting old lights back in did not work. May have fried my ecm. I will test that next if possible. Crazy if tail lights can smoke an ecm.
     
  3. someotherguy

    someotherguy I'm Awesome

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    All your fuses are not good.. you've overlooked something. There are fuses in the driver side of your dash, and also under the hood.

    Very, very unlikely to be any problem with your PCM.

    Richard
     
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  4. thinger2

    thinger2 I'm Awesome

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    2nd that. Blown fuse short to ground someplace.
    I believe the obd1 connector shares a circuit with something else, dome light dash lights? I forget.
    I do know that leds will do all kinds of strange things if you have a bad ground or short.
    So check all the fuses, not just the ecm.
     
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  5. 98chevy2500SS

    98chevy2500SS Specializes in Accessories 101

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    x2 on the fuses. I have read of some people blowing a fuse after installing LED tail lights.
     
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  6. AK49BWL

    AK49BWL GMT400 Forever!

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    The circuit routing of the taillight boards is something funky, and if you don't get the right bulbs for them, you'll blow the park lamps and brake fuses every time. Don't ask me how I know... I had one NOT blow the fuse; the bulb itself blew off half of the LEDs.
     
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  7. alpinecrick

    alpinecrick I'm Awesome

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    You guys are scaring me. I have a box full of ANTLINE and Phillips LED's for the all the exterior running lights I'm about to install...........:eek:
     
  8. AK49BWL

    AK49BWL GMT400 Forever!

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    Once upon a long time ago I came across a picture that had each bulb pin clearly labeled and showed exactly why certain bulbs don't work... And now I can't find it. But suffice to say, one of the sockets causes a dead short with some LED bulbs.

    I ripped mine off and used regular old twist-sockets on mine, using a piece of bent aluminum to hold them in place. Still working to this day..

    [​IMG]

    More info in my Sierra's build thread, about halfway down post #2

    Now there's an aftermarket on Amazon that actually uses twist sockets... If they looked identical to factory on the outside, I'd buy them myself, but they're not quite.

    https://www.amazon.com/dp/B0038BBHN...olid=328EQMK4OFHT6&psc=1&ref_=lv_ov_lig_dp_it
     
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  9. thinger2

    thinger2 I'm Awesome

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    Leds are real touchy about wiring and grounds and the quality of them is often complete crap.
    Had a customer a couple of years ago who wanted leds on a peterbilt 379 and a b train.
    We chased that shit for two weeks and lost our asses on the job.
    Bad grounds, corrosion, and cheap chinese bad out of the box parts
     
  10. Childs

    Childs Newbie

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    Thanks for the tips. Oddly enogh the new led brake lights, running lights, and reverse lights worked. They just caused something to happen. Pcm is still not responding. All interior/exterior lights work. Dash cluster only illuminates seat belt and gear indicator lights. Engine will turn over but won't fire. I read that led light conversions use load resistors that can damage an ecm. I ordered a used one already. I will look at adding a new system ground in the morning and go through fuses again.
     

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