Why won't my #*&%@# trailer lights work???

[rodee71]

I had a 4-pin trailer light plug installed on my 93 by the Honda dealer (that has been doing all my work) for my HF 40"x48" car-top type trailer. They used the plug and accessories I ordered from Cyclemax and it must be installed correctly because, if I use my matching test plug, all the little green lights on the test light work as they should: the always-on taillights, the left and right turn signals, and the brake all light up as required, so the current is there. Now if I hook the plugs up together to the brand new trailer lights, the only lights that work are the always-on taillights (and tag illumination light). I've tried a new set of lights, tried directly wiring the wires together w/o the plugs, and used my truck connection as an alternate power source and the results are always the same: No signal lights and No brake lights!? And the trailer is hitched up to the bike, just as if it were going down the road. Anybody, any ideas as to what I'm doing wrong? PLEASE!
Thanks in advance, I know somebody will point me in the right direction!

[WingAdmin]

The wiring of the trailer might not match the wiring of the bike. Some trailers have four lines only: ground, running light, left turn and right turn. The turn signals are also used as brakes (by illuminating both at the same time), in which case the turn signals flash red.

Some have five: ground, running light, left turn, right turn, and brake. In this case, the brake lights are normally separate from the turn signals, and often the turn signals are amber. This is how my trailer works.

The other option might be that the trailer wiring was done incorrectly? I know when I got my trailer, the wiring was such a mess, I ended up ripping it all out and starting over from scratch.

[rodee71]

Thanks for the reply, Scott. First off, the plug on the trailer came with a 4-pin, so I bought a 4-pin plug for the bike, assuming that that would make all the trailer lights (always-on, L or R signals, and both L/R signals lighting up for the brake light) work properly. As I wrote in my plea for help, the 4 little green test plug lights work properly when plugged into the bike harness plug. That's the part I don't understand. And I've used the original trailer lights and new out of the box lights. Neither work. The Only light coming on is the always-on. Beats me!

[bustedwing]

I have ran into this before and as Scott said but may not have cleared it up for you. If your brake lights and your turn signal are on two different bulbs then the 4 connecter will not work for you as you need another wire for the extra bulb. There's a converter made for vehicles with 5 wire to 4 wire trailer harnesses so you don't have to re wire your trailer. One other thought is your ground. If you are not positive that your ground is very good the trailer will try to ground through the hitch which only works sometimes. I hope that this helps.

[WingAdmin]

Thanks for the reply, Scott. First off, the plug on the trailer came with a 4-pin, so I bought a 4-pin plug for the bike, assuming that that would make all the trailer lights (always-on, L or R signals, and both L/R signals lighting up for the brake light) work properly. As I wrote in my plea for help, the 4 little green test plug lights work properly when plugged into the bike harness plug. That's the part I don't understand. And I've used the original trailer lights and new out of the box lights. Neither work. The Only light coming on is the always-on. Beats me!

This is a four pin connector:

Hopefully you have a voltmeter we can test with.

On the bike, you should see +12 volts between white and brown (white is ground, it's the bare one on the bike side) whenever the bike is on. I expect this is working, because you are seeing running lights and plate light working on the trailer.

When you hit the brakes, you should see +12 volts between both white and yellow, and white and green.

When you have the left turn signal going, you should see +12 volts between white and yellow, flashing, but not between white and green.

When you have the left turn signal going, you should see +12 volts between white and green, flashing, but not between white and yellow.

Let's start with that. I'm fairly sure this is going to be the case, because you said the little test lights are lighting up, but let's be sure.

If this is the case, then we've got a wiring issue on the trailer side.

[rodee71]

First off, I only have 1 bulb for all the functions, #1034's, other than the little side illuminator bulbs and tag light on the left side. And the plug is exactly the one you show, Scott. As far as the grounding goes, it must be good because if I take the ground wire off, the taillight goes out. The Honda dealer did install the Cyclemax kit, so I feel good about the parts and labor. I'm at work, but will pull out the voltmeter as soon as I get home. Thanks, guys.

[Dusty Boots]

..... The Honda dealer did install the Cyclemax kit, so I feel good about the parts and labor. ....

You've mentioned this 'Cyclemax Kit' twice, but have not said what all there was included in this 'Kit'?

Did it include a 5-to-4 pin trailer harness converter??

[Al Waters]

I just finished doing the wiring on my 2009 Wing for hauling a trailer. I used the Kuryakyn wire harness for having power under the rear fender. I then used their 5 pin to 4 pin setup for trailer lights as the trailer will come with the standard four pin flat connector. I know that I could have done it cheaper than using their setup but if I was to mess up, it would cost me more in the long run to get it straightened out. So the added expense is peace of mind to me.
You mentioned using a test light. I prefer a voltmeter as I like to see the voltage readings fluctuate for the blinkers and also be consistent with the running and brake lights. Will the wiring on the trailer be the same setup as the bike as WingAdmin has shown? It is supposed to be. That is the industry standard.
I backed my Gold Wing up to a cargo trailer I own, normally pulled by my Toyota truck and plugged it in. Everything worked as it should.
That tells me when my motorcycle trailer arrives, everything should work properly also. If not, my trailer is wired incorrectly or it is the ground.
My trailer arrives next week. I hope that you find the solution to your setup sooner.

Thanks,
Al Waters

[redial]

I have found, over the years, that the most damaged electrical item, apart from fuses, is the trailer plug that connects to the tug. It gets run over, dragged through mud and water, and rammed into the receiving socket. What I am leading up to, is that I terminate the trailer to a terminal strip, and once that is correct, I never have to touch it again.

From the terminal strip to the plug, I make up a short length of cable to act as the intermediate cable. If it gets broken/damaged, I do not have to go to the back of the trailer each time (or use mirrors) to see what lights are working. If necessary, I can test for voltage at the terminal strip, as the wiring from there back to the lights should be constant.

If I damage the plug, I can have a spare already made up and sitting in the trailer, as a replacement. And to be sure, make sure there are no 'dangling' bits to catch so that the trailer should be constant. If a light is out, it is most likely to be the bulb and not the wiring. This method takes some of the anger out of trailer lighting problems.

[WingAdmin]

Here's how I have mine set up.

On the bike, I have a six-pin female waterproof connector. This provides ground, running lights, left and right turn signals, brake lights, and a fused +12 volts used for charging a battery in the trailer. I bought an extra male connector, cut the wire off the end of it, and sealed the wire end with hot-melt glue. This is installed when the hitch is not installed, to seal the connector and keep it from corroding. You can see it installed here:

Bike side connector

On the hitch that goes into the receiver, I have a pigtail:

Hitch

One end of the pigtail is the male counterpart to the female connector found on the bike:

Plug on hitch

The other end is a standard round locking six-pin trailer connector that the trailer plugs into:

Plug to trailer

[rodee71]

..... The Honda dealer did install the Cyclemax kit, so I feel good about the parts and labor. ....

You've mentioned this 'Cyclemax Kit' twice, but have not said what all there was included in this 'Kit'?

Did it include a 5-to-4 pin trailer harness converter??

Yes. The kit was this unit: http://cyclemax.com/inc/sdetail/gl1500_ ... /129/59647.
I'm going to look into the plug n play the dealer installed when I get home tonite and check that no wires are crossed or improper ground is made. I may start all over myself re-installing it. If nothing works, I might go to LED's with the Hopkins LED adapter. I have a new pair of LED trailer lights. Just maybe.........

[Dusty Boots]

You've mentioned this 'Cyclemax Kit' twice, but have not said what all there was included in this 'Kit'?

Did it include a 5-to-4 pin trailer harness converter??

Yes. The kit was this unit: http://cyclemax.com/inc/sdetail/gl1500_ ... /129/59647.

They are two entirely different items and you need both of them in order for your trailer lights to work with your bike!!!


The way it should be wired is the ISO Trailer wiring harness connected properly to the bike and then the 5 > 4 pin converter wired to the ISO Trailer wiring harness.
If you don't have a 5 > 4 converter wired in there after the ISO harness, then the trailer lights just aren't going to work properly!!

If your trailer lights are set up the same/similar as the following trailer, then you need the 5 > 4 wire converter in order for the trailer lights to function properly

If on the other hand your trailer has separate turn signal lights as the trailer below has, then no 5 . 4 wire converter is needed. ....

Dusty

[rodee71]

You've mentioned this 'Cyclemax Kit' twice, but have not said what all there was included in this 'Kit'?

Did it include a 5-to-4 pin trailer harness converter??

Yes. The kit was this unit: http://cyclemax.com/inc/sdetail/gl1500_ ... /129/59647.

They are two entirely different items and you need both of them in order for your trailer lights to work with your bike!!!


The way it should be wired is the ISO Trailer wiring harness connected properly to the bike and then the 5 > 4 pin converter wired to the ISO Trailer wiring harness.
If you don't have a 5 > 4 converter wired in there after the ISO harness, then the trailer lights just aren't going to work properly!!

If your trailer lights are set up the same/similar as the following trailer, then you need the 5 > 4 wire converter in order for the trailer lights to function properly

15814666697_d7cb56a0fa_z.jpg

If on the other hand your trailer has separate turn signal lights as the trailer below has, then no 5 . 4 wire converter is needed. ....

15998441431_8ff18339e9_z.jpg

Dusty

That's what I was saying, I bought them both. However, I didn't do the install, my local Honda dealer did. So, rather than assume they used them both, tonight I will open it up and take a look. Thanks again for all the info, guys. I'll let you know the end results.

[Al Waters]

My trailer finally arrived. I opted for the Lumina trailer. It took about an hour and a half with help to assemble. In an earlier post I explained my wiring setup and how I tested it. When I connected the trailer four pin flat connector to the motorcycle flat connector, everything worked fine.

Its a nice trailer but needs more exterior lighting. That will be my next project.

It came with a swivel hitch so I could choose between it and the standard setup. I see discussions on both and really can't say which is better. I decided to put the swivel on.

I am trying to post a picture. I hope that it comes through.

Thanks for all the help out here. Its been very valuable for me.

Al Waters