Dimming Turn Light Question

[SeattleBob]

Hi All,
I dropped on new LED tail lights last weekend on my boat trailer to add a little extra punch to the trailer. My left side blinker has never worked that well as it has always had a very dim blinker. I have a four pin connector coming off my Honda Pilot and as I was reconnecting the lights, I was testing out each side. I connected the turn lights prior to connecting the tail lights (brown wire) and when the tail lights weren't connected the left blinkers worked fantastic, blinking in full brightness. When I then connect the tail lights to test them out, the left side turn lights dim quite a bit. I tried several times and it does the same thing. It doesn't seem to affect the right side of the trailer. Not sure what to try on this but am open to any thoughts anyone might have.
Thanks in advance.

 

[Bondo]

Ayuh,..... Welcome Aboard,.... Yer wagon has a bad ground path,.....

 

[Gary H NC]

Bondo is dead on as always.......Start checking grounds and working back from the tow vehicle...

 

[Illinoid]

Yep...99 percent of the time you can fix that by fixing the ground, other 1 percent, the bad ground you can't find;-)

 

[SeattleBob]

Thank you. So a rookie question here as I did just reground the white wire to the trailer hitch, are you saying it could be the ground on the car thru the 4 pin connector and I should try to trace that back to the ground on the car or try to ground lights somewhere else on the trailer hitch? Thanks for the help.

 

[Gary H NC]

You grounded the white wire to the hitch on the trailer or tow vehicle? It sounds like you are using the trailer frame as your ground.
If so then where does that turn signal ground wire go?
My current trailer I ran ground wires all the way back to the lights on each side instead of just grounding the white wire to the frame...
Never any issues out of them that way.

 

[SeattleBob]

Good question. I have a ground to both the car and the trailer (hitch). Both turn signals are grounded to the actual trailer back by the lights. Ironically, after all of this, I think it has to be a tow vehicle challenge as I have a pop up tent trailer that also is having problems with the left turn signal. Any thoughts on what to check on the tow vehicle (Honda Pilot) as far as the ground goes or is this something I just need to take into a shop to look at?

 

[Gary H NC]

Time to pull the plug in on the tow vehicle apart.....I bet you have some corrosion going on in the connections...
It probably has the round blade style factory plug in and they do have problems eventually..

 

[NYBo]

I believe your Pilot has separate turn signal and brake light filaments, so there is probably a converter somewhere in the trailer lighting equation.