Turn signal problem

[gbaglo]

Checking lights for trip tomorrow.
Left turn signal / brake is not working now. Old Bag was helping with hook up and says that brake was working when I pulled out of the driveway to park on street.
I have cleaned contacts and used electrical spray cleaner on them and on the 7-pin. I've used a file on the 7-pin.
Still no joy.
Had the same problem with the same turn signal two years ago and from time to time. When it's fixed, I don't know how I've fixed it but it's not working now.

[Iowa Dave]

Glen. If you have a tester the first thing to do would be to get a
good ground and put the ice pick tip on the contacts in the 7 pin to see if you have juice to all of them. If so, hook up to the trailer making sure you still have a Good ground and then go back to the trailer and take the left lens off and take the bulb out. After clamping onto a new ground, probe the socket and see if your test light goes on. If so, bad bulb. That's where I would start. I have a
tattoo that says them grounds will mess you up so I never forget . Sincerely hope this helps
Dave

[Iowa Dave]

Glen. Clean the bulb tips with some abrasive like emery paper too as well as the bulb sides
Dave

[C&G in FL]

If it were me, I would put a meter on the left turn signal pin and ground (5 and 4, normally yellow and white wires) on the tow vehicles 7 pin connector to make sure there isn't an intermittent condition. Tow vehicle lights could be working but 7-pin outlet wiring might be loose. If that turns up no problem, jump from 12 battery to trailer's 7-pin plug and see if left signal bulb comes on. That would at least indicate where the problem might be. If this has happened in the past, it could very well be a poor connection. Did TV come wired for towing or was it done after market?

[gbaglo]

I've cleaned the bulb and changed it out.
Got my testers out and I get no LEDs lit up, using the four-pin tester on that connection under the car. My recollection now is that that was the issue last time. Tried cleaning those contacts and sprayed with cleaner, but still no go.
I was thinking if it was a fuse issue at the vehicle, then the right brake light and signal wouldn't work either.
I'm gonna crawl under one more time. Had to break off cause my beer was getting warm.

[Iowa Dave]

Good thought. These's a number of variables here.
Dave

[Sandra L]

Don't you just hate it when stuff like that happens?

[gbaglo]

Bizarre.
Old Bag, who has never had a driver license, came out to help by switching turn signals and applying brakes while I used the testers.
First question was, what is the brake pedal? Followed by how do I change the turn signal from left to right? I'm under the car, trying to explain.
Anyway, I wasn't getting satisfactory results from the tester, so I put the four pin back together and plugged in the seven pin tester, resigned that I was going to have to take it in somewhere for rewiring and - it was flashing. Confirmed that left turn was actually flashing.
"But, officer, I ran though all the diagnostics just this morning and everything was working perfectly".
I don't know.

[Iowa Dave]

Hmmm I used a similar line of logic once when my bro in law and I got stopped with no rear lights one night about 6 blocks from home. We apologized, offered to leave the Jeep parked and walk home and work on it the next day. We both worked in a packing house on the kill and looked pretty rough with blood and stink covering us. The officer smiled and told us to take it easy and go straight home, which we did. There are some great policemen out there and we met one that night.
Dave

[Brian B-P]

It sounds like the 7-pin connector gets it's lighting circuit connections from a four-pin flat connector. I had one of those - it was crap. The 4-pin flat connector works for a trip at a time, but leaving it plugged in all the time leads to corrosion, because it is not protected in any effective way. A permanent wiring connection is better; if retaining the option of using a 4-pin connector is important, there are connectors with both 4-pin and 7-pin receptacles:
Hopkins Endurance Multi-Tow 7-, 5- and 4-Way Flat Trailer Connector - Vehicle End

[Ron in BC]

Originally Posted by Sandra L

Don't you just hate it when stuff like that happens?

You mean his beer getting warm?

Ron

[gbaglo]

Originally Posted by Brian B-P

It sounds like the 7-pin connector gets it's lighting circuit connections from a four-pin flat connector. I had one of those - it was crap.

Guess I need to eliminate the 4 pin. There is lots of wire bundled there, so not sure why they wouldn't go direct.

[Brian B-P]

Originally Posted by gbaglo

Guess I need to eliminate the 4 pin. There is lots of wire bundled there, so not sure why they wouldn't go direct.

Often the trailer wiring kit ends in a four-pin, so using the adapter-style 7-blade socket saves making a couple connections. In my case, I didn't have a permanent mounting bracket I liked, so fewer permanent connections had some appeal, but mostly it was convenience of using the kit's existing connector... and that I had not yet learned this lesson.