Jeep Commander Forum banner

1 - 14 of 14 Posts

·
Registered
Joined
·
2 Posts
Discussion Starter #1
Since last fall I have had some issues with the trailer tail lamps when I have my trailer hooked to my Commander. I have a 7 way to a 4 way connector(old one and a brand new one) with all lights working but the tail lights. This is with multiple trailers that are known to work with other Dodge vehicles. I have checked all fuses and none are blown unless I missed one in the cab fuse panel. I had tail lights last fall when pulling boat out of the lake and had the wires disconnected but when reconnected the tail lights were out. I did notice that there the previous owner/dealer had quite a bit of electrical tape wrapped around the wires on the Jeep side of the plug. I don't know if this was to protect the wires or if there was previous damage. If any one can help that would be great. Thanks in advance.
 

·
Moderator
Joined
·
2,248 Posts
First, Split the system in half by checking with a 12 volt test light to see if you have power at the connection. If you have lights on all three of the wires then the problem is in your trailer wiring. It sounds like yoou have already tried it with other trailers and did not get tail lights. If so then work backwards to the point where you have power to the tail light circuit. If you get power in that circuit then the problem is between the last place that you did not have power and where you did. Another thing to make sure is that you have a good ground. Often after tracing what someone thought was a lack of 12 volts the problem ends up being a loose or disconnected ground wire.

Good Luck, Take your time and you will figure it out.
 

·
Registered
Joined
·
2 Posts
Discussion Starter #3
There is power at all three wires. I have also tested this with a 4 way light tester with my dad. It is telling me that there is power to all of the lights but no power to the tail lights. At first I thought it was the 7 way/ 4 way connector due to the fact that there was some melted plastic on the 4 way side of the connector but after replacing that with a brand new one and same result. I have even taken both of the 7 way/4 way connectors and tried them with the same trailers on different vehicles and the lights worked. So my question, is there a separate fuse or relay that is not marked that may be blown? By the way, the tow package is stock on my Jeep since I ran the VIN through the dealership.
 

·
Moderator
Joined
·
2,248 Posts
OK. Lets backup. This is really pretty simple. You have four wires in the 4 way connector. White, (which is the ground wire), Brown, (which is the running lights), and the green and yellow wires are for a combination of turn and stop lights. I can't remember which is which but it does not matter, you would find out very quickly when you turned on your turn signal.

If you have power at all three of the colored wires at the rear of your Jeep then your problem is definitely in the trailer wiring and not the jeep. You either have signal power of 12 volts or you do not. If you have to, just rewire the trailer. The brown wire goes to all the running lights, (tail lights, side lights whatever light you run when going down the road. The two other wires go directly to the tail light that they control. If you turn on your blinker, you should get the turn signal on the side that the blinker controls and with the brake you get both. To identify the right or left just test the yellow or green wire with your turn signal at your 4way to see which one it is.

Now, after having typed all that I will bet that your problem is a bad ground wire to the trailer. Make sure that the white wire is connected to a good metal ground and that your tail lights are grounded also.

These circuits are really simple. The hot wire lights up the filiment in the bulb, but it has to have a good ground to work. It should not matter if it is an LED light. They work the same. In some applications you might need a resistor, but in trailer lights it is designed to work with 12 volts.

Good Luck with the trailer.
 

·
Premium Member
Joined
·
632 Posts
I suspect a ground problem also. However many people miss the 4 wire connector that comes standard with the towing package. Follow the wires on the left side of the hitch assembly - tied up under the rear bumper on the left side of the hitch with a tie wrap is a standard 4 pin connector. Cut the tie wrap and swing it down and try it to your trailer.
 

·
Premium Member
Joined
·
181 Posts
I think the point is, the 7 to 4 converter should work. Mine does the same thing.

The factory 4 pin is obviously an after thought. The 4 pin should terminate right next to the 7 pin like some other ones I've seen. Not where you need to lie on the ground to find it. Also it should be mounted better so you can put some force on plugging in the trailer plug......if the trailer wire, by chance, is long enough to reach under the bumper and off the the side that far. Pretty poor design for a "trailer towing package" on a JEEP no less.
 

·
Registered
Joined
·
887 Posts
I have no issues with a cheapy converter I picked up from Wallyworld. What brand are you guys using?
 

·
Premium Member
Joined
·
181 Posts
Mine is a Mopar. It came with the Commander. If anything should work, the factory one should. I'll have to get out my meter and see if there is power there in the plug. Does anyone know the fuse number off the top of their head for trailer running lights? (yes I can look it up, I got an owner's manual with mine. Not a useless CD)
 

·
Premium Member
Joined
·
181 Posts
In the engine bay there are 2 fuse boxes. In the one nearer the front of the car, there are 3 red 10 amp fuses. The middle one is the trailer tail light/running light fuse. Mine was blown out.
cfuse.jpg

The 7 to 4 pin works fine now that the fuse is replaced.
 

·
Registered
Joined
·
2 Posts
Not meaning to hijack the post but I am needing to get the wiring done on my 06 Commander and was wondering if anyone had a Wiring diagram for rear end pigtail trailer hookup? Or know of where I can find it without having to buy the manual.

Its a 4 flat hookup.
 

·
Moderator
Joined
·
2,248 Posts
I am not sure if this is what you are asking for, but if you have a factory towing package there is an additional connector besides the 7 way mounted on the rear. The additional 4 way connector is in a bundle of wires up under the rear bumper on a seperate pigtail that comes off the harness. If you are asking for a wiring diagram and do not have the factory towing package this might not help. Good Luck.
 

·
Registered
Joined
·
2 Posts
No, I don't have a towing package. I have the hitch but just got a 4 flat pigtail wire deal from Wal-Mart and was wondering if that would be able to be hooked up to the wiring that way instead of through the tail lights.
 

·
Premium Member
Joined
·
181 Posts
Obviously there is a wiring harness back there for the tail lights. You can splice into it if you know how to do that sort of thing. Be sure to solder the splices and coat them with some kind of weather proof goop so the splices don't corrode. That's the old school way to do it. I'm not sure if new cars like adding bulbs to the lighting circuits or not. Then damn things are awfully complex these last few years.
 
1 - 14 of 14 Posts
Top