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This is the common connector most of us have been using that plugs into the Porsche trailer wiring socket, if you already have one you shouldn't need to replace it. I took this one off my '06 Cayenne that I installed 3 or 4 yrs. ago.
7 Blade flat to 5/4 way pin LED adapterlike this
This part will need to be modified for it to work, I'll describe it below.
On the 7 Blade Flat to 5/4 pin LED Adapter you will need to first disassemble the adapter, make sure you remember the orientation of the 7 pin side, it can be reassembled 2 ways and 1 of them is wrong. IIRC 4 small screws hold the adapter together.
You will need to remove the 5th pin on the end of the adapter the trailer pigtail connects to (the flat end). This is only because the U-Haul connectors won't slide over the molded portion of the 5th pin. I just used a Dremil tool and cut it off flush so the trailer connector would install.
Next, on the 7 Blade round end you will need to remove the (big) round center connector. IIRC this just pops out and the wire can be removed (I did this modification over a year ago, going by memory here). I do remember I tried using the adapter with the center pin still installed first but it wouldn't work so I removed the center pin and it worked fine.
I tested this setup this evening on the '10 GTS at my local U-Haul store and it worked just fine (tail, both turn signals and brake lights). This arrangement doesn't require any modification to the Cayenne end, the only part you're modifying is the $15 LED Adapter.
7 Blade flat to 5/4 way pin LED adapter like this
This part will need to be modified for it to work, I'll describe it below.
On the 7 Blade Flat to 5/4 pin LED Adapter you will need to first disassemble the adapter, make sure you remember the orientation of the 7 pin side, it can be reassembled 2 ways and 1 of them is wrong. IIRC 4 small screws hold the adapter together.
You will need to remove the 5th pin on the end of the adapter the trailer pigtail connects to (the flat end). This is only because the U-Haul connectors won't slide over the molded portion of the 5th pin. I just used a Dremil tool and cut it off flush so the trailer connector would install.
Next, on the 7 Blade round end you will need to remove the (big) round center connector. IIRC this just pops out and the wire can be removed (I did this modification over a year ago, going by memory here). I do remember I tried using the adapter with the center pin still installed first but it wouldn't work so I removed the center pin and it worked fine.
I tested this setup this evening on the '10 GTS at my local U-Haul store and it worked just fine (tail, both turn signals and brake lights). This arrangement doesn't require any modification to the Cayenne end, the only part you're modifying is the $15 LED Adapter.
I'll post photos of my connector later.
Bill, is it the silver pin that you are referring to as the "5th pin" that needs to be removed?
No Frank, that is the ground (I believe) for the trailer lights. You need to remove the pin on the other end of that row of pins as it's the one that keeps you from plugging in the "4 prong flat" connector.
I'm waiting for a new set of adapters that I was going to take pics of the modification to post here, I'll go ahead and take pics of the one I've already modified to tide you over. The new adapter should be here today or Monday though and I'll document the process on it.
The adapter on the left is the LED one (already modified on both ends), the adapter on the right is a std. (incandescent) "7 blade to 4 pin flat" adapter that has always worked fine on incandescent trailer lights. You can see the pin I removed to make it work. When you look at the (trailer end) connector you can see why that pin and the surrounding plastic needs to be removed.
I also took a pic of the round end and you can see where I removed the center (big round) pin was removed. When you remove the 4 screws and open the adapter you'll see how it just sits in there, remove it and pull the wire from it's associated blade connector. I really don't understand why it doesn't work with this pin still installed but it wouldn't and it does work with the pin removed so....
Photo 1: New adapter
Photo 2: Label on back of adapter box showing wiring connections.
Photo 3: (left) modified adapter (Ctr) new adapter (Right) incandescent adapter
Photo 4: same but from "Round" end
This is the common connector most of us have been using that plugs into the Porsche trailer wiring socket, if you already have one you shouldn't need to replace it. I took this one off my '06 Cayenne that I installed 3 or 4 yrs. ago.
7 Blade flat to 5/4 way pin LED adapterlike this
This part will need to be modified for it to work, I'll describe it below.
On the 7 Blade Flat to 5/4 pin LED Adapter you will need to first disassemble the adapter (see photo 1), 4 small screws hold the adapter together. The round end of the adapter has a "key" so that it will only go back correctly one way, it's a small indentation that allows one of the covers to position correctly.
You will want to cut the (blue) wire as it goes into the back end of the "flat" connector (see photo # 3). You will need to remove the 5th connector on the "flat" end of the adapter the trailer pigtail connects to. This is only because the U-Haul connectors won't slide over the molded portion with the 5th pin in place. I just used a Dremel tool and box cutter to cut it off flush so the trailer connector would install. (photo 5 shows end result)
Next, on the 7 Blade round end you will need to remove the (big) round center connector. The other end of the blue wire you cut above is connected to the back of the center pin on the "round" end, that wire just pulls off the pin, remove it (photo 2 & 4). Next I used a punch to push out the center round pin, it needs to be punched from the inside of the adapter out, don't try to push it from the backside of the adapter to the inside, it won't go. I really don't understand why this should need to be removed since you've cut the wire but I do remember I tried using the adapter with the center pin still installed first but it didn't work so I removed the center pin and it worked fine.
Next reassemble the adapter making sure the keyed part of the round end is correct (flat end doesn't matter) and you're good to go.
This adapter modification has worked with U-Haul LED trailer lights on both my '06 Cayenne "S" and my '10 GTS.
Can you help me to understand why you went through all of this to make it work? I've been having a nightmare of a time with trying to get trailers that have LEDs to work with the Cayenne. I've tried 2 adapters so far, but the brake lights will not work due to the lamp out sensor. Will the solution you outlined here solve that problem? I tested both LED bypass adapters (7-4 blade) at the uHAUL yesterday and neither of them worked (trailer brake lights would not function). Fuses are good. Power to the blades. Help!
So I had the same problem. After MUCH research and reading through 10+ year old threads, this is what I had to do. Works as expected.
On a side note:
Through the 6 previous adaptors, I would just turn the key on without starting the car. Was getting the strobing/pulsing LED thing consistently. But if I had the engine running, it seemed to disappear. I believe that if the car battery is discharged, that's when you get the strobing/pulsing.
I made sure to charge my battery up all of the way, and that seems to have done the trick.
Now everything works *exactly* as expected, for under $30.00
I can also confirm that the Trailer Lamp-Out adaptor works as designed on my 06 CS. We towed an Airsrteam all the way down to Cabo San Lucas and then up to Fairbanks. Worked every time and I recommend you always carry a spare adaptor.
10-15-2013, 09:52 PM
U-Haul LED trailer lights work on '10 GTS (and '06 S)
