Ok. Spent half the day re-wiring the entire trailer. Was getting 8 volts (with a meter) on the left side and 2volts on the right. Nothing would light still. Had to cut off the original factory 4 prong plug. Just about broke my heart. When you have to start taking off factory stuff, its never good. Anyways, replaced the male and female now and got the left lights on. After removing right one, it sparked a little and lit up. I have a ground so don't understand that. It seems like it is using the mount as a ground.


Heres the problem now. All lights on bright. No brake or turn signals on the trailer. (They work on the truck). I doubled checked all yellow to yellow, brown to brown etc. Being all color coded, cant understand how I could possibly screw it up but I have some how. To top it off, its like 90's again today.


Sorry to keep bugging you but probably not safe for me to take it 1000 miles without proper lighting.


Thanks so much.

 

By the way jersey boy or girl. Where do you see the # of views.

 

found it.

 

I'm afraid I need to go back to the basics. Disconnect the trailer light plug completely from the truck.

Turn on the parking lights. Measure the voltage at the connector at the back of the truck between the ground pin (white) and the running lights (Brown). It should be 12V. What is it?

Turn off the parking lights. Turn on the left turn signal. Make sure it's flashing on the truck. Measure the voltage at the connector at the back of the truck between ground (white) and the left turn signal (Yellow). It should be a pulsing 12v. What is it?

Turn of the left turn signal. Turn on the right turn signal. Make sure it's flashing on the truck. Measure the voltage at the connector at the back of the truck between ground (White) and the right turn signal (green). It should be a pulsing 12v. What is it?

I just want to be 100% sure you are getting the proper voltages at the truck connector before blaming the trailer wiring or something else.

You said the trailer might be getting it's ground through the hitch connector. That is not a good thing to do. When you wired the trailer lights did you get a good secure frame chassis ground to the ground connector?

Finally - I sure would not recommend hauling a trailer 1000 miles (or any miles) without the lighting working properly. It's dangerous and just begging for an accident or ticket.

Jack

 

Just put in a new ground. The factory old one looked fine but you never know. Also replaced factory plug.


12v on brown. all running light on.


left and right signal, pulsing .01 vlts. works on truck, not on trailer. no flasher either. I am stumped.

 

Great! At least the running lights now work and that's progress.

I strongly suspect what you are seeing as .01 volts for the turn signals is really 12v turning on and off and your meter isn't fast enough to see it. Lets assume it is OK for the moment.

do you have a 12v bulb or maybe the old trailer light? I'd like to try directly connecting a bulb between the grn and wht connections at the truck end. It should flash with the turn signal on the truck. If it does, we can say the truck wiring is all good to go and we need to take the trailer lights one at a time.

 

Found my 12v testing light. The meter is a cheap one. Lights up on parking lights but not turn signals. Used old light wired before new plug & it didn't light up. I already switched the relays with the wiper relays, which say rt. & lft. tow signals & they work on the wipers. I am sooooo confused.

 

When using the test light what is the ground clip connected to? The frame or the ground pin on the truck connector?

Also - check fuses # 19 and #21 in the PDC under the hood. Probably good but at this point anything could have happened.

Jack

 

Tested using both. Only worked on the ground pin of the 4 way. went ahead and checked 7 pin & same problem. power, no brakes, blinkers


Just took the rt/lft. stop relays out and tested them. no power. power to all other relays, just not those 2. disconnected battery and used electronic cleaner, let dry, tried again, dead. is there another fuse somewhere that controls those 2. really freaking out now. only have 70k miles on it. giggled wires under integrated power module fuse box, was a little dusty but all firm. tested again nothing.


any suggestions greatly appreciated. if I have to go to the dealer it will cost me a kidney or first born.


thanks for your help

 

OMG. Found 2 20 amp fuses that control the 2 rt/lt relays. they were bad. replaced and works now. 3 days of my life I will never get back. lol. At least I got my moneys worth out of the 12v tester.


Thanks so much for your help.


Still haven't figured out why my cd player isn't working though. You wouldn't happen to know anything about that would you. It acts like its loading, then spits out and says error. Tried blowing it out with the compressor but that didn't do anything. Its the factory 6 cd changer. Dealer told me it is one of the computers that run the car but I think they were just trying to keep me coming back. No warranty for 6mths. now so learning how to fix myself.