Why are these lights continuously on and flickering?

Discussion in 'Questions From New Drivers' started by xzmpt, Aug 14, 2024.

  1. ducnut

    ducnut Road Train Member

    2,570
    7,732
    Dec 31, 2010
    SPI
    0
    T800 is a completely different cab. T660 doors shut a lot like the T600/T800/W900. The T680 has huge pass-through vents on the rear sleeper wall and built-in air leaks in the doors, so the doors shut more like nice pickup truck doors. Unfortunately, the built-in air leaks ensure your left arm and leg stay frozen, all winter long. There’s no excuse for the poor build quality of the T680.
     
    Opendeckin Thanks this.
  2. Truckers Report Jobs

    Trucking Jobs in 30 seconds

    Every month 400 people find a job with the help of TruckersReport.

  3. Cali kid

    Cali kid Road Train Member

    1,736
    2,380
    Feb 15, 2011
    IE, CA
    0
    I was just saying might help close the door. I’m aware of the differences between the cabs.
     
    ducnut and tscottme Thank this.
  4. Judge

    Judge Road Train Member

    13,198
    86,852
    Mar 19, 2014
    Arkansas
    0
    truck is haunted.
     
    TexasRiverRat and JolliRoger Thank this.
  5. kylefitzy

    kylefitzy Road Train Member

    4,634
    19,169
    Aug 12, 2007
    Kansas city,Mo
    0
    Those lights have three wires running to them. Ground, contant hot for the small light, and a switched hot for the large light. I built a set of water Mellon lights for my truck to replace those lights.

    OP: a few years ago I had a 680 that those lights would flicker and eventually just come on with no way to turn them off. Eventually I just had to unhook them.
     
    ducnut Thanks this.
  6. ducnut

    ducnut Road Train Member

    2,570
    7,732
    Dec 31, 2010
    SPI
    0
    And, the ground wire is switched by the BCM, because it’s a CAN bus system, which is why the positive wire is always hot, and why you couldn’t turn off the T680’s lights.
     
  7. kylefitzy

    kylefitzy Road Train Member

    4,634
    19,169
    Aug 12, 2007
    Kansas city,Mo
    0
    The switch must be broken on my ground then. Both lights ground through the housings. the switched power wire powers the red light and the constant power wire runs the clear light. Both are run on a three position switch that is bright-off-dim. The red light comes on with the door switch and the door lights, like the factory lights IMG_5969.jpeg IMG_5967.jpeg
     
    ducnut Thanks this.
  8. Zoltan1a

    Zoltan1a Road Train Member

    1,254
    1,510
    Mar 15, 2011
    Las Vegas, NV
    0
    my last truck had the same lighting issues. The dome lights would go on and off while I was driving. I thought the truck just took on some hitch hiking ghosts. The shop had nooo clue what to do with the issue.
     
    ducnut Thanks this.
  9. Pigdude

    Pigdude Light Load Member

    180
    576
    Oct 8, 2021
    0
    I got thrown into a 680 yesterday while my truck was down. The whole #### truck flickered. Including the transmission. It wound up on a hook. lol.
     
    Opendeckin and ducnut Thank this.
  • Truckers Report Jobs

    Trucking Jobs in 30 seconds

    Every month 400 people find a job with the help of TruckersReport.