Forum Discussion

s_N_s's avatar
s_N_s
Explorer
Nov 01, 2013

Brake light issues

I'll try to keep this as simple as possible. At the rear of the coach I have the 7 pin receptacle. I plug in my 7(which is actually 6 pin as the center is blank) pin to 4 pin adapter and it has right and left turn signal and marker lights but does not activate the brake lights thru the adapter. ???? Am I missing something here? I've always thought that the turn signal pins are the same for the brake lights. The brake lights on the back of the coach work. I should mention, I do use magnetic lights on the toad but don't see that should effect anything.

Hope this isn't to confusing.
  • Bobbo's avatar
    Bobbo
    Explorer II
    Nov 01, 2013
    This is a picture of the correct pinouts of the 7 pin connector from both the vehicle and trailer side. Note that the Right Turn light and Left Turn light are also the Brake lights. This is the way yours SHOULD be wired. It sounds to me like the converter that merges those lights for the trailer hitch isn't doing its job, or whoever wired it didn't bother with a converter and just connected the turn signals.



    ON EDIT:

    I have one of these testers. It is wonderful. (Click the picture to see ordering info.)

  • wnjj's avatar
    wnjj
    Explorer II
    Nov 01, 2013
    enblethen wrote:
    They could have wired it for brake lights on a seven pin connector with separate turn signals. The seven to four adpater would not pass the barke lights.


    There is no brake light pin on a 7-pin connector. It's for brakes, not lights. Unless you're suggesting they wires the 7-pin non-standard.

    If the coach has a 7-pin connector it should already be wired from a conveter box that merges the brake lights and turn signals onto the 2 pins turn signal pins. Then the trailer (or magnetic lights) must have only red lights that use brake and turn as the same filament.
  • enblethen's avatar
    enblethen
    Nomad
    Nov 01, 2013
    They could have wired it for brake lights on a seven pin connector with separate turn signals. The seven to four adpater would not pass the barke lights.
  • s_N_s's avatar
    s_N_s
    Explorer
    Nov 01, 2013
    I guess I'll have to take a trip over to it tomorrow and take the receptacle out and see just how it's wired. I can't believe the factory would have wired it without providing a brake light provision. I'll let ya know what I find.
  • enblethen's avatar
    enblethen
    Nomad
    Nov 01, 2013
    Here wiring diagram from Roadmaster to connect. Blue Ox are very similar.
    The wiring adapter should be on the rear of the MH and the seven pin should be wired to pull any trailer or vehicle with the seven pin cofiguration blade connector.
    Wiring diagram
  • OnaQuest's avatar
    OnaQuest
    Explorer
    Nov 01, 2013
    s N s wrote:
    K Charles wrote:
    Are the turn and brake lights separate or is it the same light on your coach?


    Now that's a good question. If I remember when I turned on the turn signal the upper red was flashing and with brakes appied the same thing. When I turned on the 4 way flashers I believe the amber lights were flashing on the coach. I guess I'll have to go back and confirm that though as really I was paying more attention to the indicator lights on the adapter.

    There's your problem. Your coach has separate turn lights (amber) and stop (red) lights.

    Your toad lights are combined in one bulb.

    You need a converter between the coach and toad.

    Check the diagrams and instructions at etrail.com
  • s_N_s's avatar
    s_N_s
    Explorer
    Nov 01, 2013
    K Charles wrote:
    Are the turn and brake lights separate or is it the same light on your coach?


    Now that's a good question. If I remember when I turned on the turn signal the upper red was flashing and with brakes appied the same thing. When I turned on the 4 way flashers I believe the amber lights were flashing on the coach. I guess I'll have to go back and confirm that though as really I was paying more attention to the indicator lights on the adapter.
  • talotto's avatar
    talotto
    Explorer
    Nov 01, 2013
    Time to get out your trusty voltmeter and do some checking. Google: "Trailer wiring adapter diagrams" and you'll find plenty of diagrams showing what the pins should do. Your problem is in one of three places: the magnetic lights/wiring, the adapter, or the coach wiring. Your voltmeter tests will narrow that down pretty quickly. If it is the coach, I'd suspect a fuse is blown somewhere. A new adapter is fairly inexpensive, and the lights wiring is pretty straightforward, likely a connection. Since you have some, but not all, lights indicates that your ground is likely good.

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