Turn Signals Driving Me Bonkers

[Nor Cal Mike]

I am having an issue with the turn signal wiring between my Casita and my tow vehicle. I hope that someone has an insight.

First I will give you an overview. I am using a Takonsha wireless brake controller which all of the electrical system goes through. It has a 7 pin male lead that plugs into the car and has a female connector on the back end of the controller which receives the original 7 pin trailer plug. The system has been and still is working flawlessly with my Subaru Forester. The problem is in a 1997 Jeep Cherokee which I purchased recently as a second tow vehicle.

When I bought the Jeep, I ordered receiver hitch and wiring adapter from etrailer.com which I installed/ I bought a 7 pin connector from a local auto supply store. It was all pretty much plug and play in regards to the brake, turn signal and tail light systems via a 4 pin flat plug which connected to the one from the wiring adapter in the car. Unfortunately the turn signal lights works only when it feel like it. However when I use my test light to check the power directly at the pins in the plug. there is always power there. I have tried jiggling the plug, checked all of my grounds, rechecked that the wiring adapter connections are tight and even replaced the 7 pin receiver plug to no avail. Numerous times as a check, I have plugged the trailer into my Subaru and the lights work perfectly every time. I don't know what to do next.

Thanks, Mike

[Borrego Dave]

It's going somewhere on the Jeep side Mike. You just haven't jiggled the right wire or connector yet from point A to B .

[War Eagle]

Mike, I had a similar problem that nearly drove me crazy before it got figured out. I had a local U-Haul dealer install brake controller and 7-pin electrical receiver on our 2002 Highlander when we bought our 2010 EggCamper. All worked fine, but every once in a while, the right turn signal didn't work. I checked everything with a multimeter - perfect. But as time went on the frequency of the turn signal not working increased, even though it still tested perfect on the multimeter. U-Haul said they couldn't duplicate my problem. I finally took it to a trailer shop that had solved a previous trailer wiring problem I had. It turned out the plastic housing of the brand new, brand-name 7-pin electrical receptacle that U-Haul had installed was cracked internally such that when I plugged in the trailer pigtail, sometimes the contacts would contact, and sometimes the contact would just push the broken plastic piece to the side and no contact made. They said it appeared to be a manufacturing defect in that receptacle that just happened to end up being installed on my car. Random bad luck. The trailer shop simply replaced the bad 7-pin electrical receptacle with yet another brand new, different brand name good receptacle - problem solved. I hope your solution is as simple.

[Nor Cal Mike]

Thanks Dale, Unfortunately I am already replaced the original 7-pin receptical with one of another type. I'll add that the one I installed in my Subaru which works perfectly, is identical to the original one I that I replaced today in my Jeep.

As mentioned in my original post, I have double checked my grounds. I have two. One is at the wiring adapter and is attached to a factory grounding point where the Jeep's tail light is grounded.The other is near the hitch and is installed into a hole that I drilled through the underside of the unibody near the spring shackle mount. I was careful to scrape some of the paint away below the wire terminal to insure good contact.

I am wondering if there might be an manufacturing issue in the wiring adapter loom similar to the one you described in your original 7-pin connector. I haven't a clue as how to test it other than installing another one in it's place and hope for the best.

Mike

[War Eagle]

I've never messed with a wireless system, but can you still plug the camper in the old fashion hardwire way, plugging the camper's pigtail into Jeep's 7-pin receptacle to see if it works that way? Also, do you have any funky radio frequency transmission wiring near where the wireless transmitter or receiver are located, like a wi-fi antenea/booster where a certain frequency from that device might be messing up the same frequency signal from the 7-pin wireless system - just happens to be the frequency your turn signal is trying to use. Just a wild guess....

[Travelin2]

Mike, I have that issue with my boat trailer periodically. I finally figured out that it was the flat contact tabs in the male plug were not making contact with the tabs in the receptacle on the vehicle. By using a small flat blade screwdriver I push it behind the tabs and bend them slightly so there is more interference pressure between the tabs as the plug is pushed in. After a few months of use they seem to flatten out again and I repeat the process.

[stevebaz]

When I had that problem it was the brake light converter box installed in my Nissan. It adapts the car harness to the 4 pin plug. its a magical mystery box. When I replaced it I used one with higher current ratings hoping for a longer working life. The first one lasted 4 years the second one was still working 6 years later when I sold the Nissan.

It was like yours testing with the trailer unhooked showed no faults. Hook up the trailer and random faults showed up. For me it was a frustrated effort that forced me to change out that converter box. If your trailer cord is long enough that plugs into the rf brake controller you can bypass the the rf controller and plug into you car to test the turn signals. The brakes wont work but you can test the lights. Check to see if the jeep has that brake light converter.

https://www.etrailer.com/t1-1997_Jee...d+Cherokee.htm

[Nor Cal Mike]

Originally Posted by stevebaz

When I had that problem it was the brake light converter box installed in my Nissan. It adapts the car harness to the 4 pin plug. its a magical mystery box. When I replaced it I used one with higher current ratings hoping for a longer working life. The first one lasted 4 years the second one was still working 6 years later when I sold the Nissan.

It was like yours testing with the trailer unhooked showed no faults. Hook up the trailer and random faults showed up. For me it was a frustrated effort that forced me to change out that converter box. If your trailer cord is long enough that plugs into the rf brake controller you can bypass the the rf controller and plug into you car to test the turn signals. The brakes wont work but you can test the lights. Check to see if the jeep has that brake light converter.

https://www.etrailer.com/t1-1997_Jee...d+Cherokee.htm

I am quoting Steve on this reply but there is merit in all of your replies. Thanks much for your help. I have concluded that the problem must lay in the Jeep side of the hookup. I just tested the lights on both the Subaru and the Jeep and currently both are looking fine. I left the trailer hooked up to the Jeep and just shut everything down and came into the house to reply to this post. I will check again later to see if it still works.

Yesterday morning early I did the same. Took a break to have breakfast then went outside and rechecked. The lights didn't work the next time and the vehicle sat untouched during the time I ate breakfast. Unfortunately, I did not check the running /tail lights at the same time. If they were not working either, that would tell me I have a grounding problem. However I think that is unlikely because I have two redundant grounds in the system.


To date I have I have checked all of the connections including those at the converter box. I have rechecked the grounds and replaced seven-pin the receptical with another type of higher quality. I have routed the original 7-pin plug around the RF brake controller by plugging it directly into the Jeep with no improvement If the problem persists, I think the issue will lay in the light converter box as Steve described above.

Mike

[Civilguy]

We had a poor connection one of the brake / turn lights on our Casita. The fault indication would show up on the dash of the Audi, so I was always immediately informed of when it was working and when it wasn't.

I messed about and determined that it was a fault at the connection between the trailer wiring and the Bargam LED light. I jiggered the clamshell connectors to increase the compression and eliminate the fault, and it worked great...

...until it didn't.

After some subsequent messing about I bit the bullet and ordered a replacement light fixture. That cured the problem completely. I decided to go with a new fixture rather than try to open the fixture and attempt a repair.

I had various issues with wiring in old cars, trailers and motorcycles over the years. There's a lot of places for a connection to go bad, often intermittently due to some corrosion or other issue. A manufacturing defect as described is just another wild card in the game. This makes it difficult to suss out and generally requires a lot of time and patience.

Unfortunately in electrical testing, what tests "bad" is bad, while things that test "good" only might be good.

Every connection has to remain a suspect until no errors are experienced. It's like a bad spy thriller, "trust no one"...

[Roy C]

Try replacing your turn signal flasher module. I had the same problem and this fixed it.

[John in Santa Cruz]

Originally Posted by Roy C

Try replacing your turn signal flasher module. I had the same problem and this fixed it.

modern cars often don't have separate flasher relays anymore, instead the flashing functionality is integrated into a chassis management computer

I note on my Ford F250, the trailer lights each have their own relays, which are controlled by the signals to the regular vehicle lights, so this isolates the trailer light power from the vehicle light power.

[ehoepner]

Take the Jeep to the Jeep Dealership and they have to get into the computer on your jeep to turn the trailer connection on. Don't know what they will change you but that is what has to be done.

[Nor Cal Mike]

Originally Posted by Roy C

Try replacing your turn signal flasher module. I had the same problem and this fixed it.

Done that. I blew the original flasher out screwing around with this problem I installed a new heavy duty flasher less than a week ago.

ehoepner, The turn / brake lights do work properly but only when they feel like it.

Well all turn/brake lights were working when I came back into the house to write my last posting. Unfortunately, in the time it took me to write that post, they changed their mind again. When I went back out to the car to give them another try, they did not work. The car merely sat stationary in the driveway with everything turned off. No bumping down the road to jar loose any connections, no motor running, no human interaction what so ever. Nada

I ordered another trailer light harness from my local Napa Auto Parts store. It will be in tomorrow. I will be very careful as I install it. I will cross all of my T's and dot all of my I's. Then I will cross my fingers...........................

[Borrego Dave]

A lot of ideas Mike for your phantom tail light hiccup. Not that this is related at all and it's maybe a one in a million but it kind of shows the problem can be anywhere. Back in 1971 a friend bought a new 350 GT Mustang and the horn would go off....when ever. Turned out that when the steering wheel hub got just hot enough to swell up a bit, it would make the horn swt make contact.

[John in Santa Cruz]

you need to borrow one of these,
https://www.amazon.com/58270-7-Way-B.../dp/B001EOWQY4

[Glenn Baglo]

I've got both the 7-pin tester and a four-pin tester.
Love 'em. I know immediately to take the vehicle to a hitch shop and get the wiring fixed. Went to Burnaby Hitch and haven't had a problem since.

[mszabo]

A question, when you are going in and out do you have your cell phone with
You?
If so try turning it off, at least the Bluetooth. Do you have a Bluetooth radio in the jeep? If so, try turning it off also.
Just a thought, I have a wireless camera system that doesn’t work well with my Bluetooth radio on.

[Nor Cal Mike]

Originally Posted by John in Santa Cruz

you need to borrow one of these,
https://www.amazon.com/58270-7-Way-B.../dp/B001EOWQY4

Yes it would be handy. But in this case it would just tell me what I already know.

[Nor Cal Mike]

Originally Posted by mszabo

A question, when you are going in and out do you have your cell phone with
You?
If so try turning it off, at least the Bluetooth. Do you have a Bluetooth radio in the jeep? If so, try turning it off also.
Just a thought, I have a wireless camera system that doesn’t work well with my Bluetooth radio on.

No Bluetooth in the Jeep. I do have a cell phone that may have bluetooth turned on. But the trailer lights work perfectly when I hook the Subaru to the system. It only runs afoul with the jeep. Also, only trailers actual brakes functions by RF signal. I am sure the rest of the functions only pass through. The brakes worked perfectly on the inaugural 300 mile trip with the Jeep. The brake light / turn signal issues showed up mid way through that trip.

[Nor Cal Mike]

Latest Progress:

I went down to Napa Auto Parts this morning and picked up the new wire harness. It is a Napa brand. I believe the first one was a Reese. I removed the old and installed the new in about 30 minutes being very careful on both the removal of the old looking for reasons why it didn't work and putting in the new making sure the grounding was secure and the plugs were properly connected. The signal lights worked as they should first try. Shut everything down for 15 minutes, went back out, turned it on and the worked again. Shut down again and will recheck in a few minutes. If she is still good, I will snap-tie the wiring out of harms way and put my interior body panels back together. Then it is on to the project I had planned for this week which is to install a transmission temperature gauge.

This afternoon if all continues to go well with the new loom, I will give etrailer.com a call to see about returning the old harness for a refund.