First place to check is at the connection between trailer and tow vehicle.
Here's 7 pin wiring from the Heartland manual. If you have your trailer manual, you'll probably be able to read it more clearly there.
View attachment 64635
Heartland's manual doesn't have a 4 pin version of the wiring diagram, but here's the generic industry pin arrangement.
Check your vehicle's fuse box, too. The running lights are on a different fuse than the other lights. Had a similar problem some time ago.
I am having the same problem with the running lights. Don't care to run without them at night or in rainy conditions. Purchased a new pigtail after developing the problem. Wired exactly like the old pigtail and put new caps and tape to make sure that it is now a quality job. Checked the fuses on my vehicle and even switched a couple around to make sure that fuses are not the problem....nothing changed. Running lights on my vehicle work fine. Brakes work, turn signals, flashers, brake lights all work fine. Did not find any fuses/breakers in the cabin of my Bighorn (2014 3270RS). Is there a set of fuses or busbar that I should be looking at to find the problem. Any help is appreciated.
I am having the same problem with the running lights. Don't care to run without them at night or in rainy conditions. Purchased a new pigtail after developing the problem. Wired exactly like the old pigtail and put new caps and tape to make sure that it is now a quality job. Checked the fuses on my vehicle and even switched a couple around to make sure that fuses are not the problem....nothing changed. Running lights on my vehicle work fine. Brakes work, turn signals, flashers, brake lights all work fine. Did not find any fuses/breakers in the cabin of my Bighorn (2014 3270RS). Is there a set of fuses or busbar that I should be looking at to find the problem. Any help is appreciated.
Already replaced the embilical cord. Checked the pigtail & good connections there. Sounds like may be in the vehicle & not the coach. Any other suggestions are appreciated.Check the metal box on the frame of your unit where the trailer embilixal cord is attached.
All your 12 volt lights are tied together in this box, plug your cord into your vehicle, turn on your running lights on and see if their is power coming into the wiring in the box.
If their is power for the running lights reaching the box then your issue is the trailer, if their is no power reaching the wiring in the box then you may have a bad embilical cord.
Already replaced the embilical cord. Checked the pigtail & good connections there. Sounds like may be in the vehicle & not the coach. Any other suggestions are appreciated.
Tail lights working. No side or overhead lights.Is there power from the embilical cord going into the metal box when connected to the truck.
Another question,,,do you have tail lights working on your trailer and no sidemarkers or are the side markers working and no roof markers or is neither working.
Sorry for these questions but this info will help to determine what or where your issue is in relation to the lights
Tail lights working. No side or overhead lights.
On most units the tail light wire runs from the front to back on the right side of the trailer to the back and then across to the left lights. They also splice in at the right light for markers and roof lights.See if there is a wire laying loose in the opening which may have come loose from the tail light wire.
This is how my unit was wired, it’s a starting point .there is no separate circuit for markers or roof lights ,they are wired wired off of the tail light wiring.
No, have not resolved the problem yet. Rewired the box, checked all the fuses, breakers in the truck and replaced the plug in the truck bed (which needed to be replaced bc the cap came off a month or so ago). Still no running lights. Had my mobile RV guy onsite on Wednesday to install toppers and he is coming back Monday morning to do a quick look at the RV to see if we can find it quickly; otherwise, will make a connection with one of the lights to get them working. He seemed to know what to do for a go around.Have you had any success in determining your problem.