Peterbilt 579 Headlight Problem - High Beams

Discussion in 'Ask An Owner Operator' started by Brandon0928, Jun 12, 2024.

  1. Brandon0928

    Brandon0928 Light Load Member

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    I have a 2018 579 Pete. Issue I’m having is with my high beams. When I turn on the high beams for the first time they will stay on “bright” up until there’s enough oncoming traffic and have to switch to dim. When I switch back to the brights 1 of 2 things happen. 1. Brights will come on for approximately 30 seconds and automatically switch to dims. 2. Brights won’t come back on at all. I have to shut off the headlights then brights work again. Replaced the headlight wiring harness. Replaced the turn signal switch. Have looked over the wires going to the node to no avail. Anybody else run into this problem ?
     
  2. boneebone

    boneebone Road Train Member

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    Newer trucks have a LCM (Light Control Module) which controls how the lights operate.

    The module may be defective or may need to be reprogrammed by the Stealership or someone with the software to do so.
     
    Long FLD Thanks this.
  3. Long FLD

    Long FLD Road Train Member

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    I second the idea of getting the computer hooked up to make sure everything is as it should be.
     
  4. snowwy

    snowwy Road Train Member

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    3rd.

    I know a 2020 that had to replace that module just to get his lights working.

    All he had was one running light right and one headlight left.