Do your MH's turn signal lights come on when braking?

[jaysigel]

I need some trailer electrical hook-up advice from someone smarter than me in these matters. I took my MH in for its yearly state inspection last month and was told that the turn signal lights come on with the brake lights when depressing the brake pedal. They passed me on the inspection, but I was told to get it fixed. When stepping on the brakes, both rear turn signals stay on, not the front ones. With the brake pedal depressed, the turn signals flash normally and the brake lights stay on normally. This seemed weird to me at first.



A year ago last month, I purchased a tow dolly at Camping World. They replaced the 7-way outlet when they installed the wiring for an electric brake controller for the tow dolly (and those brakes work). Previously, when I towed a car 4-down or a motorcycle trailer, I had to use a rewired 7-way male plug using 2 diodes. I took the MH and the tow dolly back to CW last month and told them that it was not correctly installed. I told them that I would pay for them to check out the vehicle if their installation was correct and the problem was somewhere else. They found nothing wrong with their installation and I paid them $200 for that. I did not have them fix it as they are not my repair center.



Today, trying to understand how this could be happening, I hooked up the tow dolly to the MH and watched the lights as my wife activated the brakes, turn signals and so forth. The turn signals and brake lights are activated the same way on the tow dolly as they presently are on the MH. So, using the wiring diagram on the back of a new "Trailer Life 7-Way Socket Truck End Only", I read that the red and brown wires (codes 5 and 6, respectively) are labeled "Stop and L.H. Turn Signal" and "Stop and R.H. Turn Signal". According to the 7-way outlet wiring, the tow dolly and and trailer lights must share the turn signal and brake lights. This may be okay for trailers and tow dollies, but I don't think it's supposed to be that way on motor vehicles. It seems to me that rewiring the 7-way outlet caused this and that there needs to be some diodes placed somewhere. If you agree, where should the diodes be placed?


(The common ground on the 7-way tests good. The MH's circuit board looks immaculate, located in a sealed compartment. There is no obvious corrosion there, everything else works in the vehicle. I checked the 2 onboard diodes and they conduct as they are supposed to (only in 1 direction) and they can only be plugged into the circuit board one way [arrow to the left]. I checked all fuses. The MH is a 2006 Travel Supreme 38' DP with a 400HP Cummins.)

[FIRE UP]

Jay,
We need to clarify some things here before we go on. Not being familiar with the tail light arrangement on your year/model coach, I looked them up. The one I saw showed two, RED, ROUND TAIL LIGHTS on each side. Is that you're arrangement? If so, that means you have no AMBER turn signals back there, correct?
And if that is correct, and you only have RED tail lights back there, then unless I'm missunderstanding your problem, your situation is normal. You see, with what's called a "two filament" system, you have two filaments in each bulb back there that are tail lights, not back up lights, those are totally separate.
And, being that you have two filaments, one is for regular tail light function. And the other has dual duty. One of those duties are the BRAKE LIGHTS. And, the other duty of the same exact filament is, TURN SIGNALS. So, with all that being said, when you turn your lights on via the switch on the dash, you light up the dimmer of the two filaments in each of those tail light bulbs.

But, if you turn a turn signal on, you momentarily energize the stronger/brighter filament back there. Or, if you simply step on the brakes, you also light up that same filament. But, if you have a turn signal on, AND step on the brakes, then due to the position of your turn lever on the steering column, you've canceled ONE of the brake lights and, one is still working, the opposite side of the light that's blinking.

So, yes, you will have a turn signal AND a brake light on at the same time. But, you mentioned FRONT turn signals too. Those only receive signals from the turn signal flasher, not the brake light system. So, that's how the basic turn signal/brake light signal/running light signal system works, for RED tail lights. If one has an AMBER turn signal back there, on each side, that's a whole different animal. With that kind of system, if a turn signal is energized, you now have an AMBER tail light blinking and, if you apply the brakes at the same time, you DON'T cancel one of the turn signals. You will have both sides (of the RED lens's) light up, while your turn signal is in use.

Now, with all that being said, are you saying that your rear turn signals are NOT BLINKING, when you select a turn and, are just staying on?
Scott

[Mr.Mark]

When I pulled up an '06 Travel Supreme, it shows that the rear light assembly is from a Ford Econoline van with the amber light at the top, red in the middle and the reverse lights on the bottom.

Jay, is that your set-up?

We had the same Ford rear lights on our Dynasty in a double stack. Ours didn't have the amber part as it was red and was not used.

Good luck,
Mark

[FIRE UP]

Originally Posted by Mr.Mark

When I pulled up an '06 Travel Supreme, it shows that the rear light assembly is from a Ford Econoline van with the amber light at the top, red in the middle and the reverse lights on the bottom.

Jay, is that your set-up?

We had the same Ford rear lights on our Dynasty in a double stack. Ours didn't have the amber part as it was red and was not used.

Good luck,
Mark

Mark,
Here's where I kind-a got my info from.

https://www.rvtrader.com/listing/200...L24-5005258719

It only shows two red lights on each side of the rear. Maybe there's different models of T/S for '06.
Scott

[l1v3fr33ord1]

jaysigel-

It seems strange that someone would install diodes on the MH side of the hitch connector.

Here are the minimum "standard" trailer signals (see this link for which signal goes on which pin on a 7-pin connector):

Ground
Left turn/stop
Right turn/stop
Parking = Running lights

On older coaches, especially those with separate rear turn and stop lamps, you often find the following signals, instead:

Ground
Left turn
Right turn
Brake
Parking lights

On those coaches, to make the wiring "standard" one usually installs a 3-to-2 converter, such as the Roadmaster Brite-Lite (link here), or the manufacturer may provide a "tow board" that does the same function, at possibly higher cost. See this thread for a Country Coach Magna that had its tow board replaced with a Brite-Lite, "somewhere along the way":

http://www.irv2.com/forums/f112/tow-board-417145.html

Now, converters or tow boards can go bad. When they do, functions usually stop working or there is some cross-talk. What I wonder is if CW didn't diagnose things correctly, and therefore installed diodes to combine the turn and stop signals, instead of fixing a failed tow board or 3-to-2 converter. I would be working backwards from the hitch connector to discover- and document- what CW did, and what may be there that they did not deal with, but should have. It certainly can't hurt to sketch it all out. Once you do that, you'll know where to apply your voltmeter or test light to diagnose further.

Note that none of this requires the dolly to be attached, as all the looking and testing occurs on the coach end.

[Waiter21]

On my Ford F53 chassis.

On the back of my MH, the brake lights and the turn signal lights are separate bulbs and operate independently of each other.

HOWEVER - The trailer connection combines the brake lights and the turn signals so that one bulb will serve both purposes.

[l1v3fr33ord1]

Waiter21-

Yes. You know- but others may have forgotten- that many turn signal switches have two sets of contacts. one is turn-signal-only, and the other is turn-signal-plus-brake. The turn-signal-only is used for the front turn signals, and either set for the rears, as appropriate (i.e., separate or combined turn and brake lamps). The combined set is also used for the trailer hitch signals.

This is not just a Ford thing; many diesel chassis come with similar switches, although with "smart controllers" the actual lights may not be driven directly by the turn signal switch. The Workhorse gas chassis is quite unusual as it has a jumper that enables the turn/stop combination function.

In any case, the use of the turn signal switch dual outputs often will eliminate the need for a converter. That is one fewer device to fail.

By the way, thanks for providing the Ford diagrams on your Web site.

[Jon_C]

I wired tow vehicles to trailers for 10 years almost every day. The most common problem folks would come in with was a bad ground between tow vehicle and trailer. Hook a short wire with clips between the 2 frames and if issue is gone then the problem is confirmed.

What happens is the tail lights work ok but maybe dim with a bad ground ( usually grounded only thru the hitchball)
When the brakes are applied they draw more current than the ground can provide and all the lights go out or other strange symptoms. And sometimes the ground thru the ball is ok other times not so it can be intermittent.

On my MH i tow either a jeep flat or a race trailer. My MH has separate brake lights and turn signals on back. I had to install a diode set on MH to combine brake / turn for the 7 way connector. When i tow the jeep i wanted the MH to power the jeep lights so i installed a diode set on the jeep which allows either the Jeep or the MH to power the rear jeep lights. This is just example of when why you need the diode sets.

Id check the ground first on your problem above.

[Jon_C]

And to answer your specific question, no my turn signal lights do not come on when braking. If im not mistaken it is illegal for brake lights to be any color other than red.

[Jon_C]

Another troubleshooting tool is to break the problem in half to see which side is bad. Disconnect the plug and use a battery charger to wring out the lights on the trailer side. The ground connection should max out the meter and make a large spark, if no connector does this theres a problem with the trailer ground at the other end of the wire. The electric brakes make a spark but dont max out the meter.
Make sure all lights work on trailer. To test the tow vehicle use a test light and have someone activate everything one at a time and youll need to ohm out the ground connection to make sure its good. I have also used the charger to power the tow vehicle lights thru the connector but that was on much older vehicles, not sure if it would cause issues today.

[Jon_C]

Lastly make sure your connector is plugged in all the way, sometimes its only making some connections but not all (including ground) and if its corroded use jewelry cleaner and soak the end for a few minutes then rinse, repeat until the connector is clean and spray some wd40

[jaysigel]

First, after posting a long reply, this forum tells me to log in again even though it says that I am already logged in, then loses my post! Clicking on Log In first does nothing. This is very frustrating and is happening repeatedly. Am I just writing to myself?

The picture of the Travel Supreme is not a 2006. My rear lights are housed in one unit each side and there is the single, modern, center brake light that all recent vehicles have. It has a Spartan chassis and I think this is a chassis electrical issue.

Let me clarify: Imagine that you are sitting in your RV, which has the ignition switch set to on and is not connected to any trailer or other vehicle. The parking brake is on. You are just sitting there. You step on the brake pedal and both of your REAR turn signal lights come on and stay on (not flashing) along with your brake lights. The FRONT turn signal lights do not come on. You turn on either turn signal and they function normally, flashing front and rear, whether you are stepping on the brake pedal or not. Everything else in your RV works. You have checked every fuse and diode that you could find and they all work as they should. You have never noticed this before. The only clue is that you recently had a new 7-way outlet replaced (you had one before). You wonder how there can only be 1 wire (each side) for both brakes and turn signals coming out of the outlet and how that would not affect your turn signal lights but cannot understand why the turn signals would flash normally when the brake pedal is depressed but stay lit constantly when the brake pedal is depressed and the turn signal is off. How would I remedy this or should I do nothing and live with it?

[FIRE UP]

Originally Posted by jaysigel

First, after posting a long reply, this forum tells me to log in again even though it says that I am already logged in, then loses my post! Clicking on Log In first does nothing. This is very frustrating and is happening repeatedly. Am I just writing to myself?

The picture of the Travel Supreme is not a 2006. My rear lights are housed in one unit each side and there is the single, modern, center brake light that all recent vehicles have. It has a Spartan chassis and I think this is a chassis electrical issue.

Let me clarify: Imagine that you are sitting in your RV, which has the ignition switch set to on and is not connected to any trailer or other vehicle. The parking brake is on. You are just sitting there. You step on the brake pedal and both of your REAR turn signal lights come on and stay on (not flashing) along with your brake lights. The FRONT turn signal lights do not come on. You turn on either turn signal and they function normally, flashing front and rear, whether you are stepping on the brake pedal or not. Everything else in your RV works. You have checked every fuse and diode that you could find and they all work as they should. You have never noticed this before. The only clue is that you recently had a new 7-way outlet replaced (you had one before). You wonder how there can only be 1 wire (each side) for both brakes and turn signals coming out of the outlet and how that would not affect your turn signal lights but cannot understand why the turn signals would flash normally when the brake pedal is depressed but stay lit constantly when the brake pedal is depressed and the turn signal is off. How would I remedy this or should I do nothing and live with it?

Jay,
It's nice you got back here with SOME clarification. But, you didn't really clarify whether or not you have AMBER turn signals or RED ones. As I tried to answer in my first post to you, I need to know whether or not you have the Amber turns or Red ones. You see, it makes a difference, as to the NORMAL operation, vs the issue you're experiencing. If you have Amber turn lights back there, and they are coming on WITH the brake lights, yep, Houston we have a problem.

Now, you asked about "One wire handling both turn signals and brakes". Well, that's easy. Depending on the capabilities of the person that wired your new 7-way trailer connector, and, if you do in fact have AMBER turn signals, then the normal way to wire that 7-way connector with a coach that has Amber turn signals is to use what's called a "Tail light converter".

It's a little black box, about 1/2 the size of a pack of cigarettes. In your case, it's a "3-wire to 2" wire tail light converter. There are other models out there too. But, simply put, it takes your amber turn signal out put from each side and, also from your brake light out put, and, combines them INSIDE THAT LITTLE BLACK BOX. On the output side of that little box, there is only two wires. A right turn/brake, and a left turn/brake. And those two wires, are wired into the back side of your new 7-way connector.

You see, about 99.999999999% of the toads out there will accept this type of wiring. And that's why it (your new 7-way connector) SHOULD be wired like that. Now, as for your issue, it maybe sounds as if there is some wires crossed or, somehow connected poorly or improperly. Since you said you had this new 7 way installed, it quite possible has something to do with your issue.

The picture I posted is the only one I found. If your tail light arrangement is different, well, it would be nice if you posted a picture of it so we'd all understand better. I like these kinds of issues. They're normally not hard to remedy.
Scott

[Mr.Mark]

Jay, I have the same problem when I want to post. It will lose my post and ask me to sign in again. It is very frustrating when you have a long post and it disappears.

Scott, this is what I found with the Ford rear lights....

https://www.rvtrader.com/listing/200...EME-5005254385 (photo's 10-12)

Mark