Haya,

I am having the same problem on my 02 f-350, but I have tail lights. Fuse 6, and 38 seem fine. Relay under hood is ticking. I check wire harness pig tail out @ rear bumper and tail light is there but no signals/brake. Any Ideas?

Scott
Concours owner/CT State motorcycle instructor

 

Daniels problems for trailer lighting for stop/turn/park were connection problemsbecause of a rotted/corroded ground connect at the left/rear frame.. I was a little unclear if it was a damaged splice since he added a bed trailer/camper adapter, or the factory connection, but aground gone bad none the less.. Check forgood clean tight grounds, and/or test probe the wire for turn/stop functions prior to the trailer connector as well as the coupler itself.. Here's a pic of the trailer turn relay connector in relay box #4.. You can pull the relay/s, R or L, and bridge the connections shown.. Check for12V at the bridge as well..This will take the relay/s out of the diagnostic loopand apply direct 12V (no flash) out to the harness and trailer adapter.. If you have a good ground, you should have a constant 12V out of either the R or L turn signal leg depending on which relay was bridged.. Helps check harness continuity.. With a 'grounded' test light ,check the harness before and at the trailer adapter for applied current.. DG for right, YE for left...






[IMG]local://upfiles/6756/8F061ECB40F74991B5A667B0395687F7.jpg[/IMG]

 

Haya,

Thanks a bunch! I will check what you have suggested. By the way do you have a first name? What type of riding do you do and where? Just wondering as I have been riding along time!

Thanks again Scott

 

I ride mostly sport bikes.. My current bikes are a 03 GSXR1300 Hayabusa, and I have a 1979 CBX (6 cylinder) and a few ATV's along with a dual sport bike.. I enjoy dirt/trial riding too.. I try and ride every Saturday with a group of about 20-25 friends, and we take a 'breakfast ride' out to the Nothern CA coast.. Been riding for about 35 years..

Rob...

 

I have a 2003 Ford Excursion 7.3 Diesel with no stop/turn lights on the trailer. Running lights work fine. I have checked the 2 fuses mentioned earlier in the thread with a test light and have power on both sides. The relays under the hood that were mentioned earlier in the thread are both clicking when turn signals are engaged. The only power I have is the terminal marked (+) at the wiring harness. I can't really follow the wires from the harness. They wun up above the bumper. Any suggestions?

Thanks,
Tommy

 

Hi Tommy.. Welcome..

Actually you would have the trailer battery charge (+) as well as the park/running lamps if the trailers lit up.. So,, you checked for the turns/stopsat the trailer connector and their dead.. correct?.. Are you connected to the OEM 7 pin? If using the factory trailer adapters, are both the 7 and 4 pin connectors dead for stop/turn? And 'at the harness',,, meaning you've probed the harness prior to the trailer connector/s?

 

Yes I have the trailer batery charge and park/running lamps. I tested the Turn/Stops before the connecter with a test light and they are dead before the connector. Both the 7 and 4 pin connectors are dead.

 

Would you be kind enough to share your diagrams? I'm new to the forum and don't see how to view them based on the path displayed in your messages. I just bought 03 F-350 6.0 and having problem getting trlr lights to work. Truck is with a friend picking up a newly purchased trlr 800 miles away. TKS.

 

Welcome to the site mercbenzman..

This site was updated/format changed and some of the images and illustrations aren't viewable any longer.. If I remember correctly,, that image was one I made showing the relay connector and a bidge as a circuit test..

What lights for the trailer aren't working? Stop/Turn (L/R inop for either function), Park/Running lamps?

 

Hey, I have a 2004 f350 and I am having the same problem. The only power I am getting is to the breaks. No lights. Replaced fuses under dash. The manual of course is no were to be found. Are their relays or fuses under the hood to the trailer lights?