We've got this weird issue where the left tail light of our Lance 992 comes on and stays on. Last time I had this issue it was winter and I just disconnected the battery and then the fuse for the umbilical for a few days and it went away. My wife has the TC in the desert now and reports that the light is back on again.Has anyone had an experience like this before? How do I even begin to troubleshoot if it's not happening anymore when she returns? For that matter how do I troubleshoot it if it is still happening?

Are these LED lights... I installed LEDs in my popup trailer ceiling lights and found out just a drop of water over the ON-OFF switch will turn on the LED lights... They don't draw enough current to need a strong make break contact like the ON-OFF switch would give...Also light systems that have frame ground connections really do strange thing sometimes... A burned out shorted bulb or socket can do strange things to you...I guess i would start tracing things out with a multimeter try to see what is going on...Haven't played with any of the TC DOT safety lights circuit but on my truck 7-way connection I have one of these 7-WAY TEST modules that will plug into the 7-way socket and then I go through all of the truck safety light controls and make sure the truck side is not doing anything funny... Saves me alot of time knowing where the problem might be originated from... Roy Ken

Is it really the tail light or might it be the left turn light? Tail lights are normally wired in parallel with both rear tail lights as well as the marker lights on the same circuit. Either way it sounds like you have some sort of wiring issue.

jmckelvy wrote:Is it really the tail light or might it be the left turn light? Tail lights are normally wired in parallel with both rear tail lights as well as the marker lights on the same circuit. Either way it sounds like you have some sort of wiring issue.It's the leftmost red light. So that would be tail/brake light.

RoyB wrote:Are these LED lights... I installed LEDs in my popup trailer ceiling lights and found out just a drop of water over the ON-OFF switch will turn on the LED lights... They don't draw enough current to need a strong make break contact like the ON-OFF switch would give... I have one of these 7-WAY TEST modules that will plug into the 7-way socket and then I go through all of the truck safety light controls and make sure the truck side is not doing anything funny... Saves me alot of time knowing where the problem might be originated from... Yes, they are LED lights.7 way test module! Excellent. I will get one.

That looks like the Curt test light I just bought which is available at Amazon.

Tail light stays on ... Lance 992 | Good Sam Community

18 Replies

Freep
Explorer
Aug 20, 2017
OK, I've finally had a chance to test out the new harness on the truck. I had to replace the umbilical from the Lance to the truck too since it was so corroded and was shorting out. For the last two days of driving we have had the fridge on DC and have arrived at our destination with a full battery and a cold fridge.

The new protocol works like this. I set the fridge to auto, close up the camper and then shut off the valves to the propane before we start driving. When we arrive I open the propane vales again and open up the camper. Unfortunately the fridge doesn't seem to recognize that the gas is back on until I power cycle it. This is unfortunate since I could simply turn the gas back on without going in the camper if I stopped for an extended period and didn't need to go into the camper. But that's good enough for now. I'm confident that I'm not going to run my battery down by driving with the fridge on DC.

Actually, I'm pretty ecstatic. Worrying about whether the food would stay cold with the fridge off while I was driving was a PITA and forgetting to turn it off and arriving with a dead battery was even worse.

For anyone with a Lance camper, install the Lance harness and use the correct gauge wire. You won't be sorry.
tattoobob
Explorer
Jun 17, 2017
Freep wrote:

The previous harness was not ony 12 gauge wire but it was also ~12 feet longer and we could not keep the fridge on DC while driving without having a low camper battery upon arriving at our destination.

I hope it works out for you, I also tried the drive with 12 volt running the fridge and when I got to the beach (an hour away) the Battery was just about dead so I now drive with the fridge either off or on LP
Freep
Explorer
Jun 16, 2017
Maybe you got the wrong impression or I'm misunderstanding you. To test my issue I plan to bring the camper battery down, maybe half. Then load up and take a drive with the fridge on DC. If things are working better, the fridge is still cold and the battery is charging up. I always use gas or AC when stationary and don't see being able to change that until I get Litium iron batteries with more capacity, more solar and a new fridge.

The previous harness was not ony 12 gauge wire but it was also ~12 feet longer and we could not keep the fridge on DC while driving without having a low camper battery upon arriving at our destination.
tattoobob
Explorer
Jun 16, 2017
Freep wrote:
.

I'm dying to drain the camper battery, put the camper on the truck and test it out with the fridge running on DC. But I can't do any meaningful testing until the week after next at the earliest. :(

I wouldn't suggest doing this, Gas is your best option if not running on 110v
and you don't want to drain your batteries past 12.2 volts to many times
Freep
Explorer
Jun 15, 2017
I went ahead and bit the bullet and bought a new Lance wiring harness and had the dealership install it in the truck. I made sure to tell them multiple times that it was important to have 8 gauge or better from the truck battery to the harness, in case they needed to go longer. They did come up a bit short, needed a little extra and bought themselves some 8 gauge to finish the install.

I just hope the run isn't too long.

I'm dying to drain the camper battery, put the camper on the truck and test it out with the fridge running on DC. But I can't do any meaningful testing until the week after next at the earliest. :(
Freep
Explorer
Jun 07, 2017
GeoBoy wrote:

Not if you pack the new plugs with dielectric grease.

Thanks.

In doing a little more research on fixing this, I now know why I can't run the fridge on DC while driving and why the batteries don't charge well while driving. The previous owner didn't use 8 gauge power lines from the truck to the outlet. It's just the factory wiring on the truck.

Any idea if I will need to do more than just rewire the harness in the truck? It's a 2014 Ram 3500 dually diesel.
GeoBoy
Explorer
Jun 07, 2017
Freep wrote:
Troutguy wrote:
Freep,
Looks like you found your problem.......all of that green gunk on the TC end connector.
TG

Yeah. Not quite sure how to fix it. Even if I replace everything I will still run the risk of getting water in the connector.

Not if you pack the new plugs with dielectric grease.
Freep
Explorer
Jun 07, 2017
Troutguy wrote:
Freep,
Looks like you found your problem.......all of that green gunk on the TC end connector.
TG

Yeah. Not quite sure how to fix it. Even if I replace everything I will still run the risk of getting water in the connector.
Troutguy
Explorer
Jun 06, 2017
Freep,
Looks like you found your problem.......all of that green gunk on the TC end connector.
TG
Freep
Explorer
Jun 06, 2017
It looks like it is definitely the umbilical. I finally got around to taking the camper off and this is what I found:

corrosion
It wasn't taped very well.

One end of the cable that connects from the umbilical to the truck.

The other end