Stop,tail & turn lights don't work

[Idalogger52]

2014 3155RL, have traveled 5k miles this summer w/no issues. Been parked 3 weeks at home, went to load Friday for a trip west and batteries were down to on charge, since they were original I replaced them with New Delco RV batteries. Hooked up the F350 (2017 dually) checked the trailer lights as always. No lights at the back,stop,tail,turn,marker all dead. When on either LH turn or RH turn the two top cap and front side marker lights blink.
I am thinking mice got to my wires as we have had mice in the coach before. Also my new batteries are showing low charge after 3 days sitting in the driveway plugged in. My question is where has anyone pulled the underbelly on that or a similar model, if so where is a likely spot where st&t wire and the AC power supply routed together? Dealer is almost 90 miles away and I'm not keen on pulling that distance in summer traffic with no lights.

[RichardD]

It sounds like you have a bad ground cable connections. For other lights to be blinking when you turn on your directional lights, it is more than likely a bad ground connection. A bad ground could also cause you batteries not to charge. Check all battery grounds as well as any chassis ground connections.
I hope this helps, good luck!

[dieselguy]

I'd start at your power plug on the rear of your truck. Check all functions there. If OK, then go to JBox under pin box and remove cover. Check all functions there as that will tell if your pigtail has an issue. Check ground there as well. All your fiver running lights get power from your truck, not the house batteries. House batteries do supply power to breakaway switch.
You did hook the new batteries up correctly and not reversed polarity? If so, you blew fuses in converter.

[mtlakejim]

Ditto to dieselguy

[Idalogger52]

Ground problem makes perfect sense and I did not think of that..... will check that in the morning. Thank you!

[Idalogger52]

The batteries are installed correctly. My slides work, my level up system works, every light in the coach except for one led ceiling light ( 6 total, 5 work) work. Ceiling fan,fridge , microwave all work fine. My charge wizard light was off this afternoon when we got home, was blinking 3 times per second when we left, indicating a normal charge mode........checked the truck plugs, both work correctly, checked at the junction box under the pin box, everything is working at that point, has to be somewhere past the pin junction box.

[Carl n Susan]

Based on your previous diagnostics it sure sounds like a mouse induced wiring problem. The last time I looked at my 2012, I seem to remember the wiring harness from the J box on the pin comes down into the front compartment near the batteries. It then goes through a hole in the bulkhead and along the left side above the coroplast. I think you are going to have to drop the coroplast to chase the problem. You can pull the taillights and check for voltage/continuity.

[BB_TX]

You might also try using a jumper wire at your trailer connector to test trailer wiring. Pin 4 is 12 vdc (battery). Pin 3 is tail and running lights. Pin 6 is right stop/turn. Pin 5 is left stop/turn.
trailer wiring

[Idalogger52]

I pulled the tail lights and backup lights and checked everything I could see .... no damage anywhere back there ......
good thought, thank you!

[Idalogger52]

BB ..... not sure what you mean about the jumper wire. All the wires at the junction box have appropriate power from the pickup.......those connections are all fine where the plug pigtail connects to the chassis wiring.

[mtlakejim]

I had mice chew up the wires at worst place on my old unit. They got a big bundle that included tail lights and all the tank sensors. I spent about 6 hours straight splicing it all back together

I have no sympathy for the vermin!!!!

[jcurtis934]

What bbtx was saying is that pigtail of trailer in hand and use a piece of wire to supply battery power to different lights to see what works or not.

[dieselguy]

It's odd that if a bunch of wires got chewed that no fuses have popped yet from bare wires touching … but stranger things have happened. Pull your light lenses again and see if there is continuity between frame and each ground wire on them.

You seem to had an issue initially with your house batteries charging … that's the reason for my battery question.

Like said the light wires run under your bedroom floor down to a hole in the street side front bulkhead, then on back along the street side I Beam to the tail. The curbside lights feed across the cap and rear end from that street side bundle.

[Idalogger52]

Me either

[Idalogger52]

Yeah, I keep going back to the fact this all started after putting new batteries in. I checked a lot of things but, I'll admit was really pushed for time, we were due to leave for daughters wedding that morning so I may have missed something. Probably did. Tomorrow will start over with no time hurries.

[BB_TX]

Originally Posted by Idalogger52

BB ..... not sure what you mean about the jumper wire. All the wires at the junction box have appropriate power from the pickup.......those connections are all fine where the plug pigtail connects to the chassis wiring.

Touch a wire from pin 4 on your trailer cord connector to pin 3 on the connector. Your trailer tail lights/running lights should turn on.
Touch the wire from pin 4 to pin 6. Your right turn/stop light should turn on.
Touch the wire from pin 4 to pin 5. Your left turn/stop light should turn on.
This will help give a better idea of what is working and what is not.
The symptoms you describe are common to a ground issue. But hard to believe there is one common ground to ALL your lights except the short distance from the connector to the frame.

If your lights work with the jumper, then you may have a ground issue between the truck and trailer.

[Idalogger52]

BB..... got it. I'll do that and see what works and what doesn't .
Thanks for explaining that for me!

[Idalogger52]

Thanks to all for the insight and helpful suggestions, that's why I love this this group!!!
For future reference, on our coach behind the LH tail light there is a bundle of ground wired all connected with a wire nut. 2 of those had pulled or worked loose, causing my problems. Keystone used a wire nut about 2 sizes too small then threw some black tape on the mess. Now we have the proper size wire nut !!!!

[BB_TX]

That rear cap is probably preassembled with lights wired before being set aside waiting to install on the trailer near the end of final assembly. And the wires attached with what ever wire nuts are handy at the time.