Toad Turn Signal & Brake Lights Not Working

[The Bay I]

I have the blue ox lights BX8869 on my toad. I have tail lights but don't have turn signals or brake lights. I test everything and all seems good. I test at the sockets and get a good test but when I put the bulbs back in all I have is tail lights. The bulbs are brand new so I would hope they are good but have switched with different bulbs just to make sure. I've been trying to figure this out for awhile and am getting very fustrated. Appreciate all your help.

[Elkhartjim]

Sounds like a bad ground. Did they once work?

[The Bay I]

Elkhart Jim,
Yes they did work, I ran over a bucket that ended up cutting my cable, blew fuses on the MH turn signals and haven't had turn signals or brakes lights on the toad since. I have turn signal & brake lights on the MH but only tail lights on the toad.

[Elkhartjim]

Check each end of the Blue Ox cable to make sure the pins are secure. I had the problem of the left turn and brake light didn't work on the toad and it was one end of the cable not making contact. When you look at the ends you should be able to see all the connection points and they should be even. I hope I haven't totally confused you.

Did you repair or replace the cut BO cable?

Are you using the diode system? Maybe when you started blowing fuses you blew a diode. How far back have you checked for current?

[HD4Mark]

John,
How are you testing the wiring? The only possible conditions I can think of are: Working=done, Open=missing connection, the ground open might do that but why would you have tail lights? Grounded=hot lead toughing ground or chassis but that would blow a fuse. Short circuit=wires touching each other, again should blow fuse. Doubt it is the flasher since the brake lights would still work.

Harbor freight (others too) sell a little LED tester that you can plug into a trailer plug to test and they are cheap. A VOM or one of the 12V test lights will work by going from your ground to each terminal on the socket just be careful not to ground one because it will blow a fuse. If the bulbs are dual filament there will be two little "dots" inside the socket. One should read 12V all of the time when the MH lights are on, the other 12V when brakes are applied or off/on for that side turn.

I have to wonder if the wiring got dinged hard enough to break it if there is another spot, maybe even inside the plastic where you can't see it or yanked out of a connector where it is broken.

Please don't feel insulted if I over simplified this. Trailer wiring is a giant PIA IMHO. I bought the magnetic ones for our boat trailers after getting sick of fiddling with the wiring every time I wanted to drag one somewhere.

Edit: Hope this helps if you don't still have the instructions http://www.blueox.us/PDFS/BX8869.PDF
Jim, It looks like his lights are separate sockets from the PDF not diodes. One less thing to have to test.

[shadrack]

You may see if you have fuses protecting your plug. I had the same problem and Newmar told me that there were fuses protecting the plug. Tiffin may do the same so if there is a problem, such as cutting and shorting the pigtail, it doesn't reflect all the way back thru the coach. Maybe this will help. My fuses are located in the battery compartment at the right rear of the coach. Try call Tiffin also and see if they do put fuses in the plug harness.

[Elkhartjim]

Just curious...did you get your lights working?

[The Bay I]

No, getting very fustrated. Checked everything on the toad and made all new connections still the same, tail lights but no brake or turn signals. When traveling down the road I had the radio on and turn the front fans on to help clear the front window and heard a lot of static. So I'm thinking ground on the motorhome. Going camping this weekend with 3 electricians so hoping they can figure out what is going on. Thanks for asking.

[The Bay I]

After catching up on my post I see the question about diodes but mine is the BO BX8869 light system, totally separate. I bought a new cable from camping world which is a roadmaster but thought they are wired the same. I did fix my blue ox cable and still have it.

[Elkhartjim]

Drats!!!! I hate when a plan fails. I don't know if the Roadmaster and Blue Ox are the same. Maybe a call to Blue Ox is in order.

Have you checked whether or not the power is at least at the plug on the rear of the mh? That would at least identify if its on the mh or the toad.

I used a test light when my left turn signal didn't work and verified the signal was at least at the mh plug. My problem was in the connecting harness from the mh to the toad.

Since this started after you ran over the bucket, I still believe its in thetoad wiring someplace...maybe???????

Please let us know how you fix it.

[The Bay I]

Jim, still troubleshooting it. I have put my voltage tester on the MH side and all seems to be good. I then tested the cable end (toad side) and it too gets good signals. I then went to the rear tail lights of the toad and pulled bulbs and checked the sockets. Had the turn signal there but when I put the light bulb back in I had nothing. The bulbs are new, just not sure where to go from here or if I'm testing correctly.

[Elkhartjim]

Ground problem on the bulb thats not working????

Like someone else said...wiring can be a pain in the rear.

[chasfm11]

When you said that you used your voltage tester and had good signal, is that on all lights? By that I mean, with your running lights on on the MH, can you still see a strong signal on the turn signals and brake lights when they come on?

The fastest way to isolate problems IMHO is to stay at the toad end of the cable and check everything there. All changes (running lights on and then off, turn signals on, then off, brake lights on/off) should result in solid responses. I personally like the "ice pick" style tester where I can get right into the plug. I've worked on a lot of boat trailers and problems arise due to oxidation inside the connector itself.

Let's assume that everything is good on toad side plug. Now, take a long wire and fasten it firmly to the chassis on the motor home. In this kind of a test, I don't use anything less than #14 and prefer #12 stranded. Make sure that the connection point on the MH for the wire is clean and bright. The goal is to get a "perfect" ground..

Now, activate the failing lights and while they are operating, touch the new wire to the base of the socket of the failing bulb. Does anything change? I admit that making the ground connection on the many of the new style bulbs is hard if not next to impossible.

It is possible that there were diodes in your taillight setup on your toad and that they are blown. Typically, these are 1 inch square boxes and they are mounted somewhere near where the wiring to the toad connects to the lights. Most times. the toad's cable is terminated at a plug in the front and runs along the underside of the chassis to the rear before any connections are made. The dealer that wired my first toad put the diodes in the trunk, behind some carpeting. Given your troubles and the difficulty of measuring the back to front ratio the diodes to determine whether they are good, I'd consider replacing them and seeing if that changed anything. If I were a betting man, I'd bet that this is your problem but confirming the toad cable is where I would start.

[The Bay I]

Chas, I do not have diodes on my system. When checking the lights I didn't have MH lights on and then tested turn signals and so forth. I did them separately. I think I have a ground issue and as you stated I may need to put on a ground wire to the MH chassis and then see if I have turn/brake lights. Also I saw in another post that the roadmaster cable and the blue ox cables are wired differently. I was thinking of disconnecting the plug on the toad and just testing the wires by inserting them into the roadmaster cable plug. Don't know if this will work or not. I really appreciate you and Jim's responses.