weird wiring problem

[Jestercat]

Greetings all....

Noticed when backing in after our trip last weekend that we seem to have lost brake lights and turnsignals on the PU.

Running lights are good, so I don't think it's a ground problem.

I tested the lights at the bargeman plug (TV end) and came across the following:

1. Running light circuit is perfect  

2. Left hand signal light circuit good and strong pulse (multi-meter needle moving up/down) at a reasonable flash rate

3. Left brake light circuit solid on  

4. Right hand signal light circuit okay, but weak pulse (multi-meter needle moving up/down over small distance) - not a reasonable flash rate  Noticed this same problem on our utility and boat trailers too. :confused:

5. Right brake light starts as solid on, then fades to nothing over a few seconds (almost like it is discharging the circuit somehow?)  :confused:

Kind of weird huh?

Looking for some ideas of where to start repairs?? I'm thinking the controller might be bad?

[austinado16]

I don't know what you have in the tow vehicle wiring harness, but since you have similar symptoms in your other trailers, that would sure suggest that this is a tow vehicle wiring, grounding or if there's some sort of splitter box or other controller that that is bad.

Make sure the lighting ground wires on your trailer have good connection by removing them, cleaning the trailer's frame until shiny, putting on new eyelet connectors and using those nifty little star washers and stainless screws.  Just because the ground connectors are tight, doesn't mean they aren't all corroded underneith and creating a super high resistance to ground.

Bad grounds cause all sorts of weird problems because the current begins looking for an easier path to ground and starts "back feeding" current through the system.  This can cause other lights to glow dim, in response to some other light attempting to active.

Good luck!

[jmckinle1]

I had the same problem and it seemed to be a bad control box in the TV wiring harness.  The harness only lasted 400 miles.

Unhook the trailer. Put a test light probe on the wire going into and out of the wiring harness control box to diagnose.  Ground the probe to the ground wire on your Bargman connector.

[wavery]

Not really uncommon at all.

I'm not sure how you are wired into your TV main harness. If it is with a pigtail connector harness, you will want to stick a test light probe in each of the connectors. The problem could just be a loose connector plug. If your trailer harness is spliced into your TV harness, I would suspect those connections first.

If that's not it, I would then pull the bargeman plug (TV end) out. Then remove each wire, one at a time and check for corrosion. If the slightest corrosion is found, cut the wire about an inch back, strip off about 3/8" of insulation. Then check that wire with the volt-meter. If it is now strong, clean the terminal that it goes into and reconnect it. Do that with all of the remaining wires.

If cutting 1" of wire doesn't change anything, you could have a bad spot anywhere in that wire (however, that would be rare). In that case, I would replace that entire wire.

Some vehicles have to have a controller box that makes the brake lights and T/S lights work on the same circuit. If your TV has one of those, that may be suspect also (as previously mentioned).

[Jestercat]

Okay.... checked all the wiring today.

When I apply 12V power to the pins on the trailer end, all lights function normally.  This is good, as it confirms there isn't a problem in the trailer's wiring

I checked all the grounds between the TV bargeman and the TV itself, and all is in working order with no cross connected grounds etc. This to is good.  

The signal coming from the TV right turn circuit is strong and flashing at a normal rate and strength and continues strong into the HiddenHitch tail-light controller.  This is good.

The signal coming from the TV brake light circuit is strong as it enters the tail-light controller.  This is good.  

It seems the controller is at fault somehow.  If the power going in both circuits is good, but the signal coming out the end of the tail-light controller is poor, it leads me to believe the controller is faulty. :mad:

This controller was installed at the same time as my hitch.  The wires are spliced in.  My new controller on order is an OEM plug in one, with the correct wiring harness.  This will hopefully solve my problem. :p

Thanks, I'll keep everyone posted.

[wavery]

Okay.... checked all the wiring today.

When I apply 12V power to the pins on the trailer end, all lights function normally.  This is good, as it confirms there isn't a problem in the trailer's wiring

I checked all the grounds between the TV bargeman and the TV itself, and all is in working order with no cross connected grounds etc. This to is good.  

The signal coming from the TV right turn circuit is strong and flashing at a normal rate and strength and continues strong into the HiddenHitch tail-light controller.  This is good.

The signal coming from the TV brake light circuit is strong as it enters the tail-light controller.  This is good.  

It seems the controller is at fault somehow.  If the power going in both circuits is good, but the signal coming out the end of the tail-light controller is poor, it leads me to believe the controller is faulty. :mad:

This controller was installed at the same time as my hitch.  The wires are spliced in.  My new controller on order is an OEM plug in one, with the correct wiring harness.  This will hopefully solve my problem. :p

Thanks, I'll keep everyone posted.

I think that there is little doubt that you nailed it down pretty good. GOOD JOB!!! :-()

I think that you will be heading off a lot of future problems by going to the factory controller. That was also a good move. :sombraro:

[Jestercat]

YES!

The plug in OEM wiring controller I bought off e-bay for $14 including shipping has solved my problem!

I think the shoddy job of the tech who installed the original controller led the it's ultimate demise.  I don't consider my self the best handyman :book: , but even I could have done a better job  :eyecrazy:  

I've never had reason to pull the interior panels at the rear of the Sienna where the controller was mounted - if I had, I would have made repairs to the crap splice job they did  :mad:

Long story short - the lights on the TV and the PUP are now working great!  So are both my other trailers.