Forum Discussion

ncrowley's avatar
ncrowley
Explorer II
Dec 11, 2014

Cannot Find Fuses for Trailer Plug - Solved

I am having issues with the toad plug. I do not get power for the right turn signal and the headlights. There is power applied for the left turn signal. The bus lights work fine. We are just not getting the power to the toad wiring. The wiring is fine - we have done this checking at the end of the pigtail and directly on the trailer plug itself.

We are thinking it may be a fuse issue but we cannot find the fuses. We have looked at the fuses where the 50 amp external power is plugged in and in the fuses in the bedroom panel and none are labeled trailer or anything like it. We have looked in every compartment under the bus and in the area under the dash by the drivers seat. We have looked all around the passenger seat.

It is a 2004 Newmar Nothernstar and Newmar had us look at the places they normally are and we could not find them. It is on a Freightliner chassis.

Does anyone have any other places we could look before we try and call someone in? I hate to do that because I do not have a lot of faith in repair people.

Thanks.
Class A
  • FIRE_UP's avatar
    FIRE_UP
    Explorer
    Dec 13, 2014
    ncrowley wrote:
    My boxes looked different than what was posted. Below is a picture of what I have. The right box - the one that has the trailer fuses - has the cover off of it. The Freightliner fellow said that they place these three components on a plate when they build the chassis and it is up to the coach manufacturer to place them somewhere. He said the cables are not that long so all three of them have to be somewhere behind the rear wheels.

    Here is the picture:

    http://i37.photobucket.com/albums/e58/LudmillaLilly/20141213-TrailerFusePic_zps6bd87162.jpg


    Basically Sir, that is the exact same as I have. All three components are mounted on a plate, just like yours, only mine are vertical. And I put the label on the fuse box. Again, glad you found it and can continue to address your issue(s).
    Scott
  • ncrowley's avatar
    ncrowley
    Explorer II
    Dec 13, 2014
    My boxes looked different than what was posted. Below is a picture of what I have. The right box - the one that has the trailer fuses - has the cover off of it. The Freightliner fellow said that they place these three components on a plate when they build the chassis and it is up to the coach manufacturer to place them somewhere. He said the cables are not that long so all three of them have to be somewhere behind the rear wheels.

    Here is the picture:

    http://i37.photobucket.com/albums/e58/LudmillaLilly/20141213-TrailerFusePic_zps6bd87162.jpg
  • wa8yxm's avatar
    wa8yxm
    Explorer III
    Dec 13, 2014
    I often have stated that at the Auto Makers (Ford, GM, Et-al) I think there is a contest to see how hard they can make it to service things.. I will skip the story about Henry Ford and the Carbarator, but mention the difference between a 70s Heater core replacement (Clamp hoses, disconnect, remove about a dozen screws, lift a lid, the core, drop in replacement replace lid, screws re-connect and unclamp, top off radiator) and thoday's cars, (Evacuate A/C, disconnect and seal, Dissamble half the dash....

    At RV body builders it's a different contest "Where can we hide it so the owner can not find it" applies to fuses, and GFCI's mostly.
  • FIRE_UP's avatar
    FIRE_UP
    Explorer
    Dec 13, 2014
    ncrowley,
    So, does your "black box" with the trailer plug fuses look like the the one in my pictures I posted, minus the lettering "Trailer Plug Fuses"? I did that with my Vinyl sign making machine. Also, does the "aluminum" part that you found next to your "black box" look like the one in my picture? If so, it's the Allison Transmission Controller. If it's what and where I think, your coach and ours are different makes and models but, they both have Freightliner chassis's and, Freightliners lay-out of where and how they place things, looks like it can be somewhat similar.

    My fuses, as stated, were/are under a panel, at the very left rear corner of the coach. I have to unscrew a couple of screws and hinge that panel upwards to see that fuse panel for the trailer plug. While yours, is in the Inverter compartment which, on mine, is right in front of where the panel I lift, to get to the fuses.

    Glad you found them and were able to move along with this issue. Good luck.
    Scott
  • ncrowley's avatar
    ncrowley
    Explorer II
    Dec 12, 2014
    Thanks to all that replied. After 30 minutes on the phone with Freightliner, I found them. I called Newmar again to ask about the fuses at the front of the coach in the generator compartment, but that was not them, so Newmar called Freightliner and got us connected. Twice I was told by Newmar that they would not be in the compartment with the inverter and, guess what - they were in the compartment with the inverter. I was able to recognize the fuse box because Freightliner sent me a diagram of what they should look like. They were in a box with a cover so you could not see the fuses. There was one aluminum part and then two black plastic boxes on either side. The fuses I was looking for are in the right plastic box.

    And, as we suspected, there were a number of blown fuses. We thought that might be the case because we had an issue with the plug where some of the connectors got pushed in.
  • ncrowley's avatar
    ncrowley
    Explorer II
    Dec 12, 2014
    Thanks for all the replies. To clarify - we tested at the plug in the back of the motorhome. We grounded the tester well and looked at each of the pins on the plug while we had the right blinker, left blinker and headlights on.

    The blinkers and the headlights worked fine on the coach. However, there was no voltage on any of the pins when the right turn signal and the headlights/tail lights were on. We saw voltage on the correct on the correct pin when the left turn signal was on. Therefore, there is something wrong in the coach.

    We will look for a converter and something around the cockpit. So far, we have not found any panels anywhere around the cockpit either inside or outside. We will also listen for a repeated in the battery compartment.

    I will get back to all of you with the results.
  • waroland's avatar
    waroland
    Explorer
    Dec 12, 2014
    My coach has relays that repeat the turn signal to the toad plug and are located in the battery compartment. I have had two of them quit working. Turn on the signal that works and listen in the battery compartment for a clicking noise. You may not have these relays but this is one way to find them if they exist.
  • Teacher_s_Pet's avatar
    Teacher_s_Pet
    Explorer
    Dec 11, 2014
    Our Phaeton has a breaker/fuse box in the rear PS compartment for the towed vehicle. We lost our toad brake lights the 1st year we owned it, I tapped into the coach high-level brake light and routed it to the back side of the trailer plug on the coach, so they would work on the toad. Tiffin replaced the entire breaker/fuse box under warranty due to a component failure in it.

About Motorhome Group

38,705 PostsLatest Activity: Jan 24, 2025