74 Bonair lighting issue

Discussion in 'Wiring' started by MaxedOut, Jun 24, 2018.

  1. MaxedOut

    MaxedOut New Member

    23
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    Aug 10, 2017
    I have a 1974 Bonair 1200 tent trailer. Got it last year. When I bought the trailer, previous owner said 2 of the clearance lights were not working and he did not get around to replacing them. He gave me replacements though. I intended to replace them this year.

    This year none of the clearance lights work.

    I checked the lights and bulbs are fine. I bought a couple replacement light assemblies, standard and led, and installed them. Does not work.

    Checking further I see I have brake and signal lights, but don't seem to have running lights. Not even sure if I ever did now that I think about it. Previous owners kept the trailer in excellent shape and repair, elderly guy who appeared meticulous with everything, so I suspect the issue may not be the trailer. Maybe.

    The hitch and wiring on my van were installed by Uhaul 7 years ago and there were issues with the install (wrong one installed). I did not use it at all until 4 years ago when I hauled an enclosed trailer and noticed I had no running lights and the brake lights did not work if signal lights were on. Trailer owner said he had lighting issues so I ignored it. Was just using it for 2 hours. A couple years later borrowed another trailer, just a tiny utility trailer with brake turn lights. Lights worked fine, no issue.

    In the van is a 4 pin connector with green lights that I was told by Uhaul turn on when plugged in to show all is well. When I plug in any trailer I never see any green lights. 3 different trailers, no green lights.

    How do I check my connector, and if it is good what else can I check?
     
  2. joet

    joet Well-Known Member

    3,263
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    Mar 16, 2011
    Elkins WV area
    to check the TV wiring you can use either a test light or a volt meter
     
  3. nineoaks2004

    nineoaks2004 Every meal is a picnic and every Day is a holiday

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    1,679
    Oct 15, 2006
    Graceville, Florida
    If it has been setting up, mice or squirrels might have chewed the wires, this would bw the last thing I check as it can be a booger.
     
  4. jnc

    jnc Welcome from New Hampshire

     
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  5. MaxedOut

    MaxedOut New Member

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    Aug 10, 2017
    Tested van connection and it tested good according to video. Oddly, now 1 green light shows on the connector (ground). Never did that before the test and haven't the foggiest why it would be on now.

    The 4 pin connector has Ground, LT, RT and MT which I assume means Marker Light.

    And then it hit me. I realize my van has automatic running lights. They come on automatically when the sun goes down unless I manually turn them on and clearance lights be part of the running lights. No wonder they did not come on at 2pm.

    So I plug in trailer and manually turn on running lights. Off goes green light. Off goes vans rear running lights (front remain on). On comes a dashboard alert telling me to service park lamps. :/

    So, something on trailer wiring is pooched and causing a fault in the clearance and running lights.

    Now I need to fix that issue and the new van issue. :/
     
  6. MaxedOut

    MaxedOut New Member

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    Aug 10, 2017
    Is a 10 Amp fuse sufficient enough to run van running lights, trailer running lights and clearance lights? Seems low but electrical is not my specialty
     
  7. MaxedOut

    MaxedOut New Member

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    1
    Aug 10, 2017
    Trailer plug was corroded so I replaced it. Simple task. Did not solve my issue. As soon as running lights come on fuse pops.

    I take all bulbs out of clearance lights and now I have running lights at the baxk, no popped fuse.

    I insert all clearance lights one by one and no popped fuse. Rear running lights are on, clearance lights are not on. Huh?

    OK, a couple of the clearance lights looked cruddy inside so I thought I would swap the worst two.

    Drivers side, outside rear. Red light. 1 wire. New light box installed.

    Center back of trailer. Red light. 2 wires. Both green. New light has 1 wire only. :/

    New Light has ground as part of set, so I try every combo I can think of to hook it up. No fuse pops, rear running lights are on, and now the amber clearance lights are on. Red ones are not. Progress I think.

    Testing various lighting options I discover I now no longer have brake lights. Why?

    Check box of stuff from previous owner and find a red two wire light. Wires are brown and white. I wire it every way I can think of. Same exact results as other light. Wtf?

    I take original light and reinstall it. Same issue PLUS every time I use the left turn signal both signals and the amber clearance lights flash. When I use right signal the right goes on, left is not and amber clearance is on but not flashing. Sigh...

    I reinstall right rear outside red light back to original. Same issue.

    The hell is going on???

    I pull all clearance bulbs again. Now signals and running lights work. But still no brake lights.

    I leave on a camping trip on Thursday and need brake and signal lights.
     
  8. MaxedOut

    MaxedOut New Member

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    Aug 10, 2017
    After much frustration last night trying to figure out what went wrong with my trailer I bought a set of tow lights just to have something working for the weekend.

    They don't. Long story short, the issue is with wiring harness in my van. :/
     
  9. Orchid

    Orchid Sharp Shootin' Grandma

    Ugh! Sorry, I hope you can get it resolved quickly.
     
  10. jnc

    jnc Welcome from New Hampshire

    That was painful! I'm glad you got it figured out.
     
  11. MaxedOut

    MaxedOut New Member

    23
    1
    Aug 10, 2017
    This is a crazy mess of a situation.
    • I tested van connection and it tested fine. But I went and replaced the van connection entirely just in case. Easy $10 trouble shooting. Issue did not resolve.
    • I replaced the connection on trailer (now van and trailer have brand new plugs). Another easy $10 trouble shooting. Did not resolve the issue.
    • I followed the wiring harness to the junction box under trailer, no issue, opened the box and all connections are solid and looking good. I took them all off and redid connections anyway. Did not resolve the issue.
    • I removed the main trailer ground wire, cleaned surfaces, cut wire and stripped a new segment to ensure a clean solid ground. Did not resolve the issue.
    • I replaced 4 of the 11 clearance lights (whole unit). Did not resolve issue.
    • I removed all clearance bulbs from sockets (since they seem to have been an issue since day 1). Did not resolve issue.
    Previously I purchased external tow/trailer lights that, provided I could not get trailer lights to work, I would install on rear bumper to use instead of factory lights. These external lights are meant to be permanent and mounted to trailer bumper using that as the ground. They do not connect to the 4 pin ground. This is a problem because I cannot seem to get them to ground anywhere on the trailer. No metal surface, unpainted or not, is giving me a ground for the lights. I know they work fine when grounded as I can ground them in my van or my fence. Just not anywhere on the trailer. Why?

    Different people tell me different things, most say the van is the issue. It is not sending correct signals. And since I had a similar issue on a different trailer I lean toward that thought. At that point, last Friday, I gave up. Could not figure out if the issue was van or trailer.

    Yesterday, I traded in the van for another vehicle. Van had an epic amount of issues and the repair estimate we got last week was obscene, so time for a switch. I was hoping the issue was van related so I could just lump that in with all the other issues but the issue is still there with the new vehicle.

    This should mean the issue is 100% trailer related. But to be on the safe side I went out an bought magnetic tow lights that get the ground from the vehicle 4 pin. $50 and something I know I will need again. They work 100% perfect in every way designed. I ssecure them to the bumper and will use them until I sort out other wiring issues.

    So back to the trailer for the issue.
    • Clearance lights are an issue, so I am going to disconnect them the system and see if that solves the rear lighting issue.
    • If not, I will do a fresh wire install from 4 pin to junction box and see if that resolves the issue.
    • If not, guess I need to dig deeper. :/
     
  12. nineoaks2004

    nineoaks2004 Every meal is a picnic and every Day is a holiday

    5,134
    1,679
    Oct 15, 2006
    Graceville, Florida
    Sounds like you have a ground problem. I run a ground wire from the vehicle thru the plug, then ground that wire from the plug to the frame of the unit. You did not state what the TV is. If it has yellow turn signals you will need a converter. The yellow turn signals use a separate bulb where the standard issue uses a double filament bulb, 1 filament is used as the turn and brake, the other is for the running lights.
     
  13. MaxedOut

    MaxedOut New Member

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    Aug 10, 2017
    New TV is a 2005 Nissan Pathfinder.
     
  14. MaxedOut

    MaxedOut New Member

    23
    1
    Aug 10, 2017
    Trailer has 2 ground wires.
    4 pin from TV connects to 4 pin on trailer.
    Ground from 4 pin goes to junction box under trailer and connects to a ground point (I think).
    Ground wire on front of trailer, connected to frame, goes to junction box and connects to a ground point (I think).

    I suppose the quickest test would be to remove trailer ground and see if lights work. If so, that is the issue.
    If not, remove all connections from junction box, wire in a new 4 pin and test everything.
    This will tell me if the issue is in the wires between then current 4 pin (new) and the junction box. If it works I know where the issue is.

    Tow lights will get me by for the weekend but I will get it all sorted and functional even if I have rewire everything and install all new lights.
     
  15. MaxedOut

    MaxedOut New Member

    23
    1
    Aug 10, 2017
    This week I have:
    • Replaced the harness from PU junction box to 4 pin with a new one.
    • Used ring clamps on connections instead of bare wire to bolt.
    • Redid ground connections (2) on side of trailer leading into trailer. Used ring clamps for good connection.
    • Disconnected, then reconnected all wires inside trailer leading to clearance lights (which still have no bulbs) to see if removing them from the system changes anything. It doesn't. Connected or not the clearance lights have no effect on rear lights.
    • Disconnected ground from PU front frame at junction box. When I do this no lights at all work.
    • Switched wires for left/right signal to see if it changes anything. Nope, just the expected signal reversal.
    • Cleaned contacts on rear PU lights.
    Here is where I am sitting currently. Not the same original, but not ideal either.

    Current status Lights off:
    • Brake on, both lights on. Right side is dim, left is bright.
    • Left signal works.
    • Right signal both flash.

    Current status Lights on:
    • Brake on, both lights on. Left bright. Right dim.
    • Left signal works.
    • Right signal both blink.
    • No running lights.

    Tomorrow I am towing a different trailer and will confirm TV has no issues.

    Anyone have suggestions as to where I should look next?

    I have been doing wiring on motorcycles for nearly a decade, rarely an issue I cannot resolve quickly. 4 wires on a trailer and I cannot figure it out for months. :/
     
  16. MaxedOut

    MaxedOut New Member

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    1
    Aug 10, 2017
    Towed another trailer with zero lighting issues so TV is certainly not the issue.
     
  17. MaxedOut

    MaxedOut New Member

    23
    1
    Aug 10, 2017
    Trailer junction box has been rewired with ring taps for clean solid connection. 20180724_183744.jpg
     
  18. Fless

    Fless Active Member

    Am I seeing that right, brake and running lights appear to be tied together (2nd connector from top)?

    Brake lights on trailer should be the same as the left and right turn signal wires.
    _
     
  19. MaxedOut

    MaxedOut New Member

    23
    1
    Aug 10, 2017
    That is my error. I keep calling it brake lights, not tail lights. Should read Tail/Run not Brake/Run.
     
  20. Fless

    Fless Active Member

    Here's one method that I've found to work, YMMV. Should be easy to do, wire by wire, since you can pull them off the posts.
    Disconnect trailer from TV. Ideally each ring connector on the trailer should be removed from any other connection (like the trailer pigtail).
    Take a car (or motorcycle, riding mower) battery and connect the negative post to your trailer ground.
    Connect the positive post to any one of the non-ground trailer wires. See what lights up or is activated. If you get cross-lighting (like both brake and running lights at the same time), suspect a bad brake light bulb or socket.
    If you notice a problem with all of the lights after testing, inspect and clean all trailer grounds. Re-test.

    EDIT: a voltmeter would be a wonderful tool to use to test the actual voltage of each circuit.
    _
     
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