Running lights don't work

[Manitou]

I know the fuse block where the loose wire is, but not which specific wires/fuse is the culprit. My rear running lights only work intermittently (head lights, brake, and signals are fine). I snipped the wire ties and remounted the fuse block and that worked for a while. I'd like to snip the wires responsible for the running lights and crimp in a separate fuse (generic part from an auto parts store).
Anyone know definitively which fuse and wire colors?

thanks!

[Blue~Go]

By "running lights," do you mean the marker lights around the roof or the Ford parking light type running lights? I could read your question either way.

I have things to say based on what I have found but don't want to address the wrong thing.

[Manitou]

Both the tail lights and the marker lights seem to be on the same circuit.

[A Rooney]

On my 2001 premier,the one time my running lights did not work,it was due to a burnt fuse,Trailwagons took the power from the stock ford distribution box under the hood at fuse 14,and ran it to their accessory fuse panel under the steering wheel.This fuse is in a exposed panel to the left not the box covered fuse panel under the steering column as well.On upscale models this fuse panel which has a handful of slots I believe handles heated cups or mirrors whatever,on my premier there is a single fuse in the top slot.this fuse allowed chinook to add the upper marker lights to the running light circuit,thus when you turn on your headlights both the running lights and marker lights come on together.if you are missing running lights,but have marker lights,this fuse is probably not the culprit.Interestingly enough fuse 14 also directly supplies backup lights,but not through the fuse under the steering column,on a recent trip my backup lights would not turnoff,I put black tape over them while driving,and pulled the fuse manually,after stopping or during the day to switch off and on my running lights.I suspected perhaps rodents damage to a wire.but the culprit was a small relay in position c under the hood in the distribution panel adjacent to fuse 14.that is the limit of my experience perhaps something I related,could prove useful.Rooney

[Blue~Go]

[Edited to add: I see Rooney posted while I was typing, so I hadn't seen his post. Sounds like his rig may be different; but I know of other Chinooks that are done just like mine, so I guess you will have to see how yours is.]

Yes, at least they are on my rig. But from your initial description I wasn't sure if you mean the markers and tails.

So, since you do, here is what I know for my generation of Concourse, as built.

1) Chinook didn't use the usual Ford wiring to power the taillights. Instead, they took the "cutaway and stripped chassis" trailer light wiring (two wiring connectors provided by Ford) and used one of them (the one that powers the basic trailer functions vs. the "extra" ones) to power the taillights and the marker lights. But wait, there's more...

So, I knew that Chinook had used this "schnozzle" (as I call it because the Ford end connection sort of looks like a periscope) to wire the taillights, because when I got my rig I wired in a new trailer lights connector. For one thing, I like a 7-way style plug (even if not using 7 ways), and for two, I needed one of the additional wires (the reverse light one, to power my trailer's surge brake lockout solenoid). So okay, I crawled under to disconnect the original four-way trailer connector. I had the Ford "camper wiring kit" drawing, so I knew what I was looking for (where the four-way joined the schnozzle). But wait, what are these OTHER wires attached to the trailer wiring schnozzle? And they go up into the Chinook floor...?!?

Long story shorter, yep, Chinook used those wires to power the Ford taillights. Good to know, since it's unconventional. I tucked that away for future reference and finished my trailer wiring job. Trailered many miles with no problems, until...

One night (of course it was at night, since it involved lights), I was towing a cargo trailer and when I turned on my lights as it got dark, I could see they were not lighting up (the trailer lights, some of which I could see in my side mirrors). Huh, when I had hooked up, not three hours before, I had checked all the lights and they were all working perfectly. At just about this time, my buddy who was behind me mentions that I also have no taillights (we had walkie-talkie type radios). Groan.

So we pull into a rest area, and I spend a few hours groveling in the dirt under the Chinook while trucks whizz by inches from my ankles. I knew it must have something to do with how Chinook did that wiring, but it took me awhile to piece it all together. So here is what it turned out to be (a combination of).

1) What I knew already, that Chinook used Ford's trailer wiring schnozzle to power the Chinook taillights.

2) And they ALSO used it to power the Chinook running (marker) lights.

3) The reason this trailer caused a problem was that it had a LOT of lights, and none of them were LED.

4) And the really tricky (and somewhat stupid IMO) part is that Chinook, apparently in an effort to be tidy and logical (that part is good), not only used the Ford trailer towing wiring that Ford ran to the rear of the frame (by the trailer hookup), but they THEN ran a (long, skinny) wire from right back there ALL THE WAY up to the added Chinook fuse block that's by the driver's left shin (Labeled "Marker Lights" and having a pretty small fuse of 7.5 amps (upper left slot of the added fuse block). They then ran another long, skinny wire ALL THE WAY BACK to the trailer lights connector and the taillights, and then more long, skinny wires forward to the marker lights. Do we have enough long, skinny wires running the length of the rig yet? And of course powering a bunch of non-LED bulbs (Chinook marker and taillights) PLUS whatever lights one's trailer may have.

The reason I had never blown the fuse before is that my usual trailer has all LED lights. My solution that night was to remove about 75% of the lights on the cargo trailer, leaving the tail/brake lights, and the rear marker lights. My friend was behind me anyway, so I figured I could limp to the next rest area (this one was full and we were perched in a non-parking area close to traffic). I then made the rest of the trip in the daylight, and then ordered all LED lights for the trailer. With those, the Chinook fuse didn't blow.

So, my question to you is, have you added ANY lights via using your trailer hitch/wiring? Are they non-LED? (non-LED draw much more is why they are a problem). If so, that's where my suspicion would lie first.

Just raising the fuse size may be a risky proposition as there is a lot of (did I mention) LONG SKINNY wire on that circuit. And some of it is bundled (reduces ampacity). Every wire size has its rated ampacity, and that tells you how high you can fuse it. I don't know the size of all of the wires in that circuit, so I didn't want to just put in a larger fuse. There is a lot of wire (to potentially cause a problem). So, as I wrote above, my solution was to be sure any trailers I tow have low demands (LED lights). IF I were going to upgrade it, I'd probably re-wire so as to NOT have that super long wire going back/forward/back/forward, etc. (to the tune of 20+ feet each way). (Rather if it needed to be re-fused that could happen aft. Maybe slightly less "satisfying" to not have it all at the fuse block, but electrical function has to be considered as well. There are other electrical choices too, but I've probably gone on long enough for now.

So summary is that unless Chinook made some big changes, your Ford taillights, Chinook marker lights, and the lights on anything you are towing are all powered by the wiring pigtail Ford intended to power just the trailer lights. And it runs back and forth and back and forth under the rig (near driver's side frame rail, and through the driver's footwell cover). So it's pretty maxed out. Adding too much draw on the trailer wiring (lights) can blow fuses.

Other ways to work with it are using LED trailer lights (not a bad thing anyway), and/or changing Chinook marker lights to LED. I imagine one could change taillight bulbs too, but I haven't looked into it. I do know you have to make sure to keep the reflector property of the stock taillights (friend who converter other brand RV to LED taillights had to add three passive reflectors to rear of rig).

If you've added anything to your rig in the way of trailer connector powered objects, that's what I'd suspect first.

Here are some supporting documents:

Excerpt From Ford's extra wiring document, showing the cutaway and stripped chassis wiring "schnozzles." Chinook used the brown one to (also) power its Ford taillights and body marker lights via the fuse shown in next attachments.

Drawing from 2000 Chinook manual depicting their added fuse block by driver's left shin. This drawing is for the Concourse. Premier has only one row but marker lights fuse is also the top one, also 7.5 amps (according to adjacent drawing in manual).

Photo of actual fuse block in 1999 Concourse. "Missing" fuse previously powered the black/grey tank "auto drains" (shudder!).

[A Rooney]

Our wiring does vary,the photo you post shows 2 rows of chinook added fuses under the steering column,my 2001 has a single row,your photo shows separate fused circuits for marker/driving lights,on my rig these are combined to a single fuse,at the top circuit position.Cant say,but I guess these circuits are powered like mine from the 30 amp fuse in position 14,at the power distribution box under the hood.I do know that in regard to the faulty relay C ,I believe the manual listed it as controlling backup and Towing lights.but I want to check that next time I head to my rig.rooney

[Blue~Go]

Rooney,

I think it got a bit buried in my post, but what you describe vis-a-vis the two-row vs. one-row added fuse blocks is the "usual" difference between a Premier and a Concourse. So not necessarily a year thing, but more of a model thing. In my original post, I edited the drawing from the 2000 manual so the Concourse part might appear larger, and only made note in the text about the Premier difference (since OP has a Concourse).

Here are both of the diagrams, which are side by side in the manual (2000 manual in this case since I had it handy). My 1999 Concourse is as this manual describes also, as it happens.

[A Rooney]

Thanks,I did not recall seeing that diagram,strange since there are plenty of empty fuse slots in even the premier that they did not separate the running and marker lights there as well,which seems like it would give you a greater degree of safety.Still if your wanted to verify if the green 30 amp fuse in the power distribution box under the hood at position 14 was controlling these circuits on the rig in question seems fairly simple to pull it.and see if you have backup/running/marker lights/.?my guess would be between 2000 and 2003 (production chassis years)they are consistent but I am just guessing.Rooney

[Blue~Go]

The night I was "stuck" in the rest area with the non-working tail/marker lights, I did check all of those big fuses in the Ford fuse box under the hood. Some of them have names that look really promising, like "trailer relay" and etc. In my case those were all good (I made sure by both testing them, and by switching them around with known working ones, since many of them are "repeats" from slot to slot).

Not to say one of those could not go bad, but in my case they were all fine. I also did the same check of every single one of the Ford fuse box fuses that are by the left driver's shin area. Those were all fine too. But in a way it makes sense that the problem was with the "marker lights" fuse that Chinook added. It's a lot of lights, and a lot of long/skinny wire runs on a 7.5 amp fuse. In fact, I have to wonder why it doesn't blow all the time when you think of the taillights, all those marker lights, and whatever trailer lights you have all being incandescent (back in the day, and still now in some cases). How are those not always drawing more than 7.5 amps?

As a side note, when I went to shop for LED lights for the cargo trailer that had so many lights it blew my fuse, I found a number of posts (Amazon and eTrailer reviews) by folks who had similar problems (trailer light circuit blowing). The Haulmark cargo trailers have a LOT of marker lights, and they were originally all incandescent. The only difference being that those folks (with typical cars) didn't have a mystery, because their trailer lights simply quit working. We have the added factor of the Chinook tail and marker lights being on the Ford trailer light circuit (who would guess that one?).

[kdarling]

Even in my '94, I think they used the trailer wiring.

Which drives me crazy because the stock Ford wiring has separate circuits for the brake and turn signal bulbs... thus I had expected my rear yellow turn lenses to light up separately from the red brake lens. But oh no. They light up together.

So now I keep meaning to rewire the taillights to use the separate light Ford setup.