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1stinLA.
Wondering if someone can help me troubleshoot this, Im new to wiring so not familiar with proper terminology, etc.The right taillight turns on fine as a MARKER light, but it is not turning on for either brakes or turn signal. I got a brand new tail light from basscat and it does the same thing, so I dont think its the light itself.I tested the truck plug. I set multimeter to ohms, black wire to the ground on the truck plug and red to the trailer hitch and got a good reading. I then set it to volts, black wire to ground on the truck plug, and checked the other wires. The yellow and green wire BOTH show constant voltage when the brakes are applied and blinking voltage when each turn signal is on. From this, it appears to me that the truck plug is working properly. Im not clear which prong on the light receptacle corresponds to each wire, so not sure where or how to test further to isolate the problem in the trailer wiring. What should I do next to troubleshoot this? Ill try to post a picture….http://images.yuku.com/image/jpg/470efb … 8062c6.jpg Also, how the heck do you get the tail lights into the cutout on the fender? The old one is super tight, but the new one seems totally impossible. Tips?Thanks in advanceLast edited by Macintosh on June 29th, 2015, 7:10 pm, edited 2 times in total.
Not sure what age trailer you are working on.If the new light is doing the same as the old, yes, it is a wiring issue.Connect the truck to the trailer and turn on the right directional signal. Look for a splice in the right side harness, likely a butt connector. Use your volt meter and check from the butt connector to a clean trailer ground. Confirm that you have the blinking (on/off) voltage at the “goes-in” side of the butt connector. Then check the “goes-out side” for the same. Tug on the wires and make sure that they do not pull out of the connector. Corrosion can do that and worse. It is likely that one of the joining points has failed.Good luck.
To get the new light in, you should remove the gasket from the trailer and place it over the light first. Then it should go in the hole with a bit of persuasion.
Macintosh wrote Im not clear which prong on the light receptacle corresponds to each wire, so not sure where or how to test further to isolate the problem in the trailer wiring. What should I do next to troubleshoot this? Ill try to post a picture….http://images.yuku.com/image/jpg/470efb … 8062c6.jpg Also, how the heck do you get the tail lights into the cutout on the fender? The old one is super tight, but the new one seems totally impossible. Tips?Thanks in advanceFirst, look at the rear of your “light” and you should see the female pins labeled Ground, tail, and signal/stop. Then put your male connector that you have in the picture near the pins so you know which pins are corresponding. Now put your voltmeter in the plug to check for voltage.Everyone does things differently but the way I get my light into the hole is to “install the rubber gasket into the trailer first”. Then pull your plug through the gasket and plug it into the light. Then push the light with the plug into the gasket until it bottoms out against the back of the gasket. This always works for me.Everyone should believe in something. I believe Ill just go fishing!
JEH, I couldnt remember which way worked. Since the photo shows his gasket in the trailer, I thought he had probably tried it that way. What I really remember is one way works…..one way doesnt
Thanks guys. Its a 2003 trailer. The holes are labeled, I hadnt seen that– but I also figured out how to test that so figure Im “learning to fish”! However, regarding fitting the gasket and light…unless “a bit of persuasion” includes a large rubber mallet, the new one aint going on. The old one is extremely tight if I push the gasket in first then the taillight from behind. The new one is significantly tighter. It truly feels like Im DEFINITELY going to break it to get it in the hole???Last edited by Macintosh on June 30th, 2015, 12:06 pm, edited 1 time in total.
I just tested with the voltmeter–Im getting voltage at the light receptacle on the trailer both for the marker ligts and blinking voltage for the turn signal, but only the marker lights are working? I tried my new light and got the same result…this doesnt seem like it should be possible, am I doing something wrong?
Check ur ground makesure u have good CONTACT. to get the light in the hole. I have used DAWN dish washing detergent. Just as a lube2013 PANTERA 2MERCURY 200 PRO XSMINNKOTA 80LB FORTREX25 fury
How do I make sure I have good contact? When I use the voltmeter on the prongs of the trailer-side plug I get good voltage for both the marker and the turn signal, but only the marker works on the light itself–both the new and the old light. I would think if the ground was bad, that the marker lights would not work either?
Put your meter back on Ohms and check the bulbs themselves by putting the black lead in the ground, and the red to the marker light side and see what the reading is, you may have to change scales on the meter to get a reading, then put the red lead to the stop/turn side and you should get the same.
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