No taillights,running lights or dash lights.

[Rontherepairer]

I have a 2012 Tho Challenger with no working taillights,running lights or dash lights. Brake lights, headlights, turn signals and backup lights all work. There is no power at rear of rv to these lights. Wiring harness under the rv is intact. The fuse in the power distribution box that controls these lights is good and there is power to that fuse. Other fuses that might be associated with these lights all check out ok. The chime associated with these lights is also not working. With all the fuses I have checked it does not appear to be a fuse. Any advice?

[MJC62]

Headlight switch?

[cavie]

All those lights are uasually on the same fuse. The dash lights are on it so you will know when the fuse is blown. How did you check the fuse???? it's chassis wiring issue. Se if you can find a chassis wiring diagram.

Got a volt meter or light probe? Light probe is the easiest to use. the ice pick looking kind with light in the handle. check power to the switch and power leaving the switch.

[Rontherepairer]

Originally Posted by MJC62

Headlight switch?

That was the first item I replaced. No change.

[Rontherepairer]

I used a light probe to check power to the fuse that controls those lights. Power is present. Also checked relay for tow vehicle taillights and it is good. I also put a new headlight switch and no change. Thanks for the tips tho.

[cavie]

I gott ask. Why change the switch if you have voltage on both sides?

Follow the hot wiring back to the rear stopping along anywhere you can find access and poke it with the light tester.

Did you find the fuse that provides the power? You also need to find the ground connection for this circuit.

[Rontherepairer]

I was on the road when I realized the problem so with no time to study the problem I ordered a light switch from rockauto and had it sent to the campground. It was wishful thinking. I know with absolute certainty I have power from the battery to the power distribution box . Confirmed by test light. I also know I have power leaving that box bc fuse is good. Here is where I start to assume. I assume I have power to and from the headlight switch bc the headlights work. There is a power interruption between there and the rear of Rv . Tomorrow I am to receive the ford DVD for the F-53 chassis for that year to see if there is a wiring diagram for guidance. This and the DVD are my last attempts before I take it to the Thor dealer which is not close by.

[cavie]

Originally Posted by Rontherepairer

I was on the road when I realized the problem so with no time to study the problem I ordered a light switch from rockauto and had it sent to the campground. It was wishful thinking. I know with absolute certainty I have power from the battery to the power distribution box . Confirmed by test light. I also know I have power leaving that box bc fuse is good. Here is where I start to assume. I assume I have power to and from the headlight switch bc the headlights work. There is a power interruption between there and the rear of Rv . Tomorrow I am to receive the ford DVD for the F-53 chassis for that year to see if there is a wiring diagram for guidance. This and the DVD are my last attempts before I take it to the Thor dealer which is not close by.

.
use the test light and prove it There is more than on circuit one that switch. Head lights will be on a different fuse then the rest..

[abjbrtd]

Sounds like you've done a good job trouble shooting the 12v side of the circuit.
If you haven't worked on the ground side of the circuit it's time.

I would suggest starting with a clearance light, easy access to both sides of the circuit.
If the running lights by the rear wheels are also out start with one of these.

Good luck, bad grounds are always the hardest trouble.

[Rontherepairer]

The running lights in front of the rear wheels work with the turn signals but not with the parking lights. I did begin to think that it might be a ground problem that developed bc of the age of the vehicle. It has been my experience when the ground becomes faulty the lights are intermittent not constantly out which is more indicative of a power supply problem. Also the manufacturer will put in multiple grounds for redundancy. Hence the reason a wiring diagram could be very helpful at this point. I will check the light switch for power in and out for taillights. Also something I would like to put out there for a response. What about the ICC switch which cuts power to the running lights when you activate it? Could it be the source of the problem?

[abjbrtd]

Originally Posted by Rontherepairer

The running lights in front of the rear wheels work with the turn signals but not with the parking lights. I did begin to think that it might be a ground problem that developed bc of the age of the vehicle. It has been my experience when the ground becomes faulty the lights are intermittent not constantly out which is more indicative of a power supply problem. Also the manufacturer will put in multiple grounds for redundancy. Hence the reason a wiring diagram could be very helpful at this point. I will check the light switch for power in and out for taillights. Also something I would like to put out there for a response. What about the ICC switch which cuts power to the running lights when you activate it? Could it be the source of the problem?

AHHA, we have a new prime suspect .

Have you used it recently? Should be easy access and to test.

[Crossleyt]

Originally Posted by Rontherepairer

The running lights in front of the rear wheels work with the turn signals but not with the parking lights. I did begin to think that it might be a ground problem that developed bc of the age of the vehicle. It has been my experience when the ground becomes faulty the lights are intermittent not constantly out which is more indicative of a power supply problem. Also the manufacturer will put in multiple grounds for redundancy. Hence the reason a wiring diagram could be very helpful at this point. I will check the light switch for power in and out for taillights. Also something I would like to put out there for a response. What about the ICC switch which cuts power to the running lights when you activate it? Could it be the source of the problem?

I found just behind the headlight switch, where Thor spliced in the dash ICC switch, the flat spade connector had become separated. Reconnected it, and tail and running lights now work. It was driving me crazy, because all the fuses were ok.

[robertstoeckle]

Sorry if already covered but I only have a quick minute. Look for a grounding issue in the chassis. .... my issue that no one could find under warranty and later, easily found by Ford dealer ... out of warranty

[rudyhehn]

For the record, I'm impressed you found the problem.

[Rontherepairer]

Rudyhehn I learned a valuable lesson. Need the wiring diagrams bc it makes it so much easier. The diagrams are a road map to where to test. You can keep the testing simple like using a test light.

[Popfla]

Originally Posted by Rontherepairer

Rudyhehn I learned a valuable lesson. Need the wiring diagrams bc it makes it so much easier. The diagrams are a road map to where to test. You can keep the testing simple like using a test light.

So....you found the problem ?

[Rontherepairer]

Yes the problem was a spade connector right after the head light switch that controls all the parking, dash and running lights. The builder had improperly connected the two pieces and the connection heated up melted and lost contract. It was sloppy workmanship.

[Randy]

I know this is an answer to an old post but I had the same problem. Mine was the spade connection placed on the marker Switch wire out. Brown with white stripe wire. It was burnt and melted the plastic that was on the connection. Replaced with new spade connections and it works fine now. I thought it was fuses, light switch and myriad of other things since my coach is a 2012 Challenger 37kt and a little older. I suggest if others have this problem do a good visual behind the dash panel first. Might save yourself a lot of time and energy, albeit it is a pain to get back there and look.
BTW,,just came back from 6800 mile trip out west from NC. She performed flawlessly. Gas engine v10 did the trick. Only issue I had was when I pulled up at the house at the end of the trip the stairs wouldn’t go up. just ordered my new motor to replace the almost 10 years old motor.

[HMCSW]

Originally Posted by Rontherepairer

I have a 2012 Tho Challenger with no working taillights,running lights or dash lights. Brake lights, headlights, turn signals and backup lights all work. There is no power at rear of rv to these lights. Wiring harness under the rv is intact. The fuse in the power distribution box that controls these lights is good and there is power to that fuse. Other fuses that might be associated with these lights all check out ok. The chime associated with these lights is also not working. With all the fuses I have checked it does not appear to be a fuse. Any advice?

My dealer's solution would be " only drive during the daytime."