1. Welcome to Tundras.com!

    You are currently viewing as a guest! To get full-access, you need to register for a FREE account.

    As a registered member, you’ll be able to:
    • Participate in all Tundra discussion topics
    • Transfer over your build thread from a different forum to this one
    • Communicate privately with other Tundra owners from around the world
    • Post your own photos in our Members Gallery
    • Access all special features of the site

Bed light wiring help, please

Discussion in 'Lighting' started by coreman23, Feb 10, 2018.

  1. Feb 10, 2018 at 8:47 PM
    #1
    coreman23

    coreman23 [OP] New Member

    Joined:
    Jan 20, 2018
    Member:
    #12319
    Messages:
    18
    Gender:
    Male
    First Name:
    Cory
    Vehicle:
    2018 4wd Crewmax Tundra
    I’m trying to finalize my bed light install and having some issues. I’m not too experienced on electrical, so please excuse my ignorance.

    I did find the correct wires to tie into my cargo switch. My problem is when I try to hook up more than one light, the lights are very dim and the cargo light cuts out. I have a positive and a negative coming from the cargo lights. The 1st pic is 1 of the 4 bed lights I’m looking to install.

    If I hook the positive (red) from the cargo switch to the red on my rock light and the negative (black)from the cargo switch to the negative of the rock light, it’s super bright and the cargo light stays let. If I try to tie any other lights in, they dim very low and the cargo light shuts off.

    Any tips for a newbie on how to properly install all 4 lights?

    D6C099F5-54C5-43F2-A1B7-8E8691B57120.jpg
     
  2. Feb 10, 2018 at 8:49 PM
    #2
    TXRailRoadBandit73

    TXRailRoadBandit73 RUNNIN' WITH THE DEVIL RÖCKIN' N RÖLLIN'

    Joined:
    May 30, 2016
    Member:
    #3487
    Messages:
    48,526
    Gender:
    Male
    First Name:
    Adam
    RGV, TEXAS
    Vehicle:
    Still searching for my Fundra
    None yet
  3. Feb 10, 2018 at 8:56 PM
    #3
    831Tun

    831Tun crazy Bastrd

    Joined:
    Jun 7, 2016
    Member:
    #3549
    Messages:
    10,982
    Gender:
    Male
    First Name:
    Warren
    Santa Cruz
    Vehicle:
    '16 CM limited
    TC LT w/ king 2.5 C/O and bypass, ADS bypass rear, Toytech shackles, TRD dual exhaust dumped, KM3 37s on Method standard +18. N_Fab front bumper, Westin rear w/ hitch relocate, RCI skids, Desert Eagle tranny skid, All Pro sliders, ARB dual compressor, 5.29 gears and ARB rear locker
    Sounds strange. But first off, don't ground to the switch. Find a good ground to the body. There's one behind the cover, driver side, lower left.
     
    NewImprovedRon likes this.
  4. Feb 10, 2018 at 10:02 PM
    #4
    coreman23

    coreman23 [OP] New Member

    Joined:
    Jan 20, 2018
    Member:
    #12319
    Messages:
    18
    Gender:
    Male
    First Name:
    Cory
    Vehicle:
    2018 4wd Crewmax Tundra
    The 1st pic here is where my positive (red) wire is hooked. And the 2nd pic the wire (black) is hooked up there. Those are the two wires that run back to my lights. I’m assuming the black is the ground, but maybe that’s wrong?

    0DBC2954-7A2C-4595-930B-CC68F4031B3C.jpg
    6C7CB197-56A0-4D72-A66F-48418E90D7CC.jpg
     
  5. Feb 10, 2018 at 11:57 PM
    #5
    831Tun

    831Tun crazy Bastrd

    Joined:
    Jun 7, 2016
    Member:
    #3549
    Messages:
    10,982
    Gender:
    Male
    First Name:
    Warren
    Santa Cruz
    Vehicle:
    '16 CM limited
    TC LT w/ king 2.5 C/O and bypass, ADS bypass rear, Toytech shackles, TRD dual exhaust dumped, KM3 37s on Method standard +18. N_Fab front bumper, Westin rear w/ hitch relocate, RCI skids, Desert Eagle tranny skid, All Pro sliders, ARB dual compressor, 5.29 gears and ARB rear locker
    I'm not very good with electrical stuff but if you're able to hook up one light successfully, and additional lights are causing dimming, my guess is you're drawing too much power from that circuit. I estimate your lights are 9w and only draw .35 amps each so I'm a little surprised.

    So, the solution would be to use a relay. You use the + wire from the cargo light circuit as the trigger (pin 86)
    pin 87 to the lights. pin 30 fused from the battery. 85 can be grounded in the engine bay.
    Your lights (black) can be grounded to the ground bolt behind driver side kick panel.
    [​IMG]
     
    NewImprovedRon likes this.
  6. Feb 11, 2018 at 8:38 AM
    #6
    NewImprovedRon

    NewImprovedRon Hey! Get off my grass!

    Joined:
    Jul 8, 2015
    Member:
    #1501
    Messages:
    13,248
    Gender:
    Male
    First Name:
    Ron
    Bentonville, AR
    Vehicle:
    2015 Radiant Red TSS Doublecab 4X4 Off Road
    Deck rail system, Bed divider, door sill protectors, LED reverse light bars, Aries Bull Bar with 28" 180 watt LED light bar, LED step lights, LED bed lights, driver-side grab handle, TRD Rear Sway Bar, BedRug bed mat and tailgate mat, Morimoto Fog Lights, more to come.....
    So you have 4 lights you are trying to mount, each at 9 watts? That is a total of 36 watts or 3 amps total, if I understand correctly. All of your led light ground wires can be grounded to the frame in the most convenient locations available. Make sure that your grounds are solid - check out the continuity with a multimeter. Just remember that the grounds are equally as important as your hot wires. What flows out, electric-wise, has to be able to return via the ground wires. You may need to lightly sand the area around the ground points if painted or would otherwise block a good connection. I have had the "dim lights" issue as well and tracked it down to a break in a ground wire. It was suggested that you may want to use a relay in your wiring and I would probably do that as well based upon the number of amps you are adding to the existing circuit. You can use the cargo switch as your "trigger" wire to your relay and not have to worry about overloading the circuit. If you elect to use a relay, remember to place an in-line fuse in your relay connection to the battery.
     
    Berdine and 831Tun like this.

Products Discussed in

To Top