Trailer brake and blinkers don’t light with lights on

Factory tow package with 7 pin connectors. On the trailer, when the lights are not on, the brake lights and blinkers work. When the lights are on, you can’t see the blinkers or brake lights.

I took the cover off the bulbs and they have 2 filaments. They work as expected ... EXCEPT the brighter filament is on with regular lights and the light filament comes on when braking or blinking. The bulbs only go in one way. So with the cover on you don’t see the difference between the bright filament and the bright+lighter filament.

Do I have the wrong bulbs?
Do I need new covers (they’re red and look fine)?

I think the wiring is good because there is one for each side blinker (2) and only one for the actual lights.

So I’m good in the day but at night no one sees my brake lights or blinkers.

THANKS!!

 

It sounds like whoever wired your lights mixed up some wires, change the wires to their proper location on the taillights fixture. Or, do you have running lights (clearance lights), or just taillights? If just tail lights and no other lighting you could swap the wires in the trailer portion of the 7 pin. Normally, not always, your running light wire is brown, ground is white, left turn yellow, & right turn green.

 

Thanks -- You're probably right about the wiring at the taillight itself. i'm going to take a look later today. The running lights along the side do turn on with the headlights, which also fires up the bright filament on the tail lights. My guess, if I get into the back of the light on the trailer is that I would see 2 hot wires coming in on each light. one for the tail/running and another for the turn/stop signals. If I swap those it should light the correct filaments. I'll dig more into this in the afternoon and report back.

For the 7 pin connector portion, I must be missing something because it's not clear to me what I would do different. Using the example below there is a single #3 Tail / Running lights input and then an input for each turn/stop (#1 and #6). So I don't know what I would swap in this case? If there were a L tail/running and a R tail/running I could just swap those with the L/R turn/stop, but that's not the case.



THANKS!!!

 

[QUOTE="
For the 7 pin connector portion, I must be missing something because it's not clear to me what I would do different. Using the example below there is a single #3 Tail / Running lights input and then an input for each turn/stop (#1 and #6). So I don't know what I would swap in this case? If there were a L tail/running and a R tail/running I could just swap those with the L/R turn/stop, but that's not the case.



THANKS!!![/QUOTE]
Yeah, disregard what I said, it won't work. I have no idea what I was thinking on that part. Sounds like the wires got mixed up in the housing