left light works only when others are not on???

[nicknight]

By itself my left turn signal on it works.
But as soon as I turn on my car lights it will not work.....it will not work at all even for signaling?

I have a toyota corolla and a 4wire flat harness.
Both bulbs under the lens do light when signalling.

What am I missing?

???

 

[G-Daddy]

Re: left light works only when others are not on???

The first thing to check with any trailer light issues is the ground. I have had similar problems in the past and 90% of the time it is the ground. Now the first thing I do on a new or used trailer is to run a separate ground wire to each light on a trailer.

 

[BatDaddy1887]

Re: left light works only when others are not on???

...it really is the ground 90 percent of the time as G-Daddy says. But, in the spirit of good tip-manship, unplug your 4wire plug and clean it off really good. I use Tarn-X (silver polish) that stuff is acid and I'm very careful....I brush it over the metal on both the plug and the jack, until the metal is bare once again, then I spray wd40 and wipe it all off dry, then apply dielectric grease liberally to all connections...especially after cleaning the ground. Take your bulbs out and inspect and clean the contacts on both the bulb and the housing, and again apply the grease. I hope you get it fixed for safe towing!

 

[bruceb58]

Re: left light works only when others are not on???

Its the ground.

Don't run the seperate ground wires. Make sure every light had a good frame ground and your connector also has a good frame ground and you will be fine. Running seperate grounds magnifys your troubleshooting down the road when you end up having another problem.

I would also suggest never using anything with an acid in it. Unless you can get every trace of acid off the connector, you are asking for a headache down the road.

 

[stevegrant1]

Re: left light works only when others are not on???

Sometimes all you need to do is clean your 4-wire connector good. Check all of your wiring for any defects.

 

[smokeonthewater]

Re: left light works only when others are not on???

it IS the ground on that one light.... may be in the socket or between the fixture and the frame.... If it were the ground in connecter at the tow vehicle you would have problems with ALL the lights
The reason it works without the other lights on is that it is back feeding through the tail light element and through all the markers and tails on the vehicle and trailer.... this provides a ground path for the brake light but since it goes through all the other markers they share the load and don't get enough wattage to light up.

 

[bruceb58]

Re: left light works only when others are not on???

I have a toyota corolla and a 4wire flat harness.
Both bulbs under the lens do light when signalling.

You do have a converter right? Since your car has separate turn and brake lights, you need a converter that allows the use of one light(brake and turn) used on a trailer.

 

[nicknight]

Re: left light works only when others are not on???

update: OK..I was offline for a few days and cameback. I was so confident in the grounding solution that I bought the wire and rigged it up....it worked!

I did not see the suggestion NOT to run a new ground wire until just now...but it is now done. I will check and clean all the connections when I get some free time and daylight.


thank you so much