Trailer Wiring Problems, need help!

[unibagel]

OK So I have this Harbor Freight trailer and I'm wiring it up to my 85 Vanagon Westy. My father had the trailer and wiring converter box hooked up to his 90 Miata with no problems. I can't seem to get the trailer to respond correctly, it seems like sort sort of issue with the Left side. Here's what happens:



Ign off, Parking lites on, Eng off:

-RS of trailer side marker and tail lite on

-LS both off



Ign off, Haz on:

-RS tail lite only flashes

-LS both side marker and tail flash





Ign on, left turn signal actuated:

-RS tail lite flash only

-LS both side and tail flash



Ign on, Westy running, Haz on:

-RS both working correctly

-LS Both side markerand tail light flash



Brake lights work correctly in all cases.



LS tail lite seems not as brite as the RS.



What the heck am I doing wrong here?



Chris

[RGS Paul]

This is utterly impossible to diagnose without knowing what wires you spliced into to steal signal to the trailer. I'd suggest you sit down with the wiring diagrams for the van, trailer, and converter box and figure out the logic paths to the trailer right now, that should tell you where the problem is.

Paul
_________________
'87 Syncro 7-Pass. Adventure Touring Vehicle
"Simplicate, then add lightness." Colin Chapman

[crazyvwvanman]

Check for a weak or missing ground on the trailer left side lights fixture.

Mark

[unibagel]

Thx Mark, I removed and cleaned the gronds for each light and that seemed to clear up 90% of the problem.

Now the LS tail lite is noticibly dimmer as the parking lights are on. But when the brakes are pressed, the RS is noticibly dimmer although they both lite up. Any suggestions on that???

[crazyvwvanman]

I assume you are using one of those converter boxes. I have had a lot of grief getting some of those to work unless the connections are all clean and good. I have had a few of the boxes act up and/or die. In any case when a light is dimmer than it should be there is a weak connection.

Mark

[unibagel]

Ok I cleaned off all of the trailer grounds, but it made no difference.

What I did notice is that you are physically able to install the RS light bulb 180 deg. out of phase (cheap Chinese stuff!). So the bright side of the bulb (brake light) would illuminate constantly when the parking lights were on instead of the dim side. Once I installed it correctly, the lights work as designed! Doh! Problem solved!

[crazyvwvanman]

I have a couple HF trailers myself. I got tired of dealing with lighting issues and installed LED tail lights they put on sale sometimes. Much better, brighter, and less sensitive to weak wiring connection since they use much less amps. No bulb filaments to break either.

Mark