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I made a harness that had a pair of 1157s in it. If for nothing else, this would be a good test light. I hooked it up and still got the warning. I then removed the Polak connector and the harness fell off. It turns out the person who installed the Polak connector didn't push it in all the way. I put it back together and my harness worked. It looks like the Etrailer adapter is fine and the LEDs work without having to buy a Module or Suburban. It looks like I will be on this forum a while longer.
I've fought with LED trailer lights on my 2005 S for a couple of years. I tried several isolation units wired into the trailer but they either burned out or just never worked properly. In the end the only reliable solution is to add ballast resistors to simulate the incandescent bulbs. It's also the cheapest solution.
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Originally Posted by Peter Carroll/Toronto
I've fought with LED trailer lights on my 2005 S for a couple of years. I tried several isolation units wired into the trailer but they either burned out or just never worked properly. In the end the only reliable solution is to add ballast resistors to simulate the incandescent bulbs. It's also the cheapest solution.
Of course in that scenario, if the LED lights fail, you will have no warning indication on the MFD; in other words, you are defeating the bulb diagnostic (and display) that is causing the problem in the first place....sort of a Catch 22.
Tried to pick up my new Aluma trailer with LED lights and electric brakes today - wohoo! I think the dealer saw me drive up in the Cayenne and already smelled trouble. Whereas the Brake Controller and trailer brakes worked, the trailer brake lights didn't - not even with the ETrailer adapter with the resistors connected to a 4 to 7 adapter. Was I tempting fate??
The only solution will be to wire additional brake lights on the trailer, activated and connected to the trailer brakes. I will also wire two 100 ohm, 1 Watt resistors in parallel as the wires come into the emergency battery box in the trailer.
BTW - I did see a nice new black Suburban for sale on the drive home.....
Last edited by Frank 993 C4S; Mar 15, 2011 at 06:33 AM.
On my Cayenne I tried several "black box" conversion modules and either they didn't work or worked for a while until they burned out. I went back to basic resistors - 6 or 10ohm 25W I think. They resistors work perfectly...
When you install resistors, be careful where you put them. They get HOT! i.e. don't pit them in a plastic battery box. Mine are pop riveted to an aluminum piece that is bolted to the trailer chassis to dissipate the heat.
Talked to the folks at Trailex and they said they have a proven adapter that interfaces with the tow vehicle wiring ( 2011 Cayenne) and works. hope so as I will be there next month to pick up the new trailer and pull it back to Texas.
Talked to the folks at Trailex and they said they have a proven adapter that interfaces with the tow vehicle wiring ( 2011 Cayenne) and works. hope so as I will be there next month to pick up the new trailer and pull it back to Texas.
Please keep us posted, and we wish you success. Just make sure Carl (very knowledgeable as you know) double checks it does work properly with current owners of '11 Cayenne's. Maybe even ask him if you can communicate with them. Three weeks ago, think he told me, the LED's would not work easily with electric brakes (recommended surge) and left the ball in my court to check with the dealer. BTW, my very large Porsche dealer never installed hitch adapters for any 2011 Cayenne's and one for all earlier models.
I get my new Cayenne in about 6 weeks. The trailer shop I buying the trailer from is an old Porsche tech and sells lots of Trailex's. He told me they will NOT do LED's with a Cayenne, or VW ... as hasn't been successful work having it properly as a "plug and go" like a Denali. Technology is frustrating until we get it right with some more benchmarks and us as early adapters. Good luck.
Last edited by amfp; Mar 15, 2011 at 08:30 PM.
Reason: typo
All is well and I'm happy. I did not go the resistor route as I did not feel comfortable putting them in the plastic emergency battery compartment. I asked the trailer folks to simply add two additional brake lights that are linked to the trailer's electric brake circuit and it works like a charm. No warning lights inside the car.
If you are buying the Trailex with surge brakes, you should be fine with the ETrailer adapter that has the additional resistor in it. If you have electric brakes, that's a whole different story and I wish you luck.
Valley makes a couple of different adapters that solve this LED trailer light problem. Sounds like someone listened to all these complaints. Found them on e-trailer for about 15 bucks
BTW: thanks for all the information over the last 6 months. I've learned a ton about my 2012 Cayenne before it arrived 4 weeks ago (Got the 6 speed manual transmission...very unique for a vehicle of this size today...never owned an automatic and didn't want to start with my 1st SUV. As an added bonus I'm getting 24 mpg's in mixed driving and save 3K on MSRP. Not sure why there isn't more demand for them in the States).
There is a wealth of information here. I'm sure there are many like me who read and learn for a long time before ever making a post.
Valley makes a couple of different adapters that solve this LED trailer light problem. Sounds like someone listened to all these complaints. Found them on e-trailer for about 15 bucks
Currently using a utility trailer without brakes and standard incandescent bulbs. In the market for a new enclosed utility trailer and many of the higher end trailers with Torsion suspension come with LED standard. My Rennlist reading of older posts set off alarm bells when I had trouble finding torsion suspension setups that came with incandescent lights. Like Lewis, I was amazed that my 2012 Cayenne didn't speak natively with LED. I felt much better after finding a cheap plug-N-play solution. The adapter should work with either type of brakes.
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