John H

I searched and could not find an answer. I have an 05 Cayenne S. It has the Pollak 7 blade part already installed. I have several 7 blade to 4 pin adapters. Here's my problem: When I plug the trailer in, all of the lights come on. However, neither the turn signals nor the brake lights work. I swapped out the LED lights for old style incandescent bulbs thinking this might help. It did not.

Upon further investigation, I check with a volt meter the pins on the 4 pin adapter. The unshielded pin was the ground sure enough. Here's where it gets weird. With brake light only illuminated on CS, all three pins are hot. With only taillights on, all three pins are hot. With only blinker on, all three pins are hot.

I checked the 7 blade part (Pollak) same thing. I removed the Pollak part and the other connector from Porsche does the same thing.

Can anyone explain this to me? It makes no sense and I feel like I am either missing something really obvious or my truck wiring is F'd.

Thanks in advance.

John H

Anyone used something like this to tap into the actual truck lights?

Trailer light power module

nosubt2

I am no trailer expert but I know if dealing with any European car, the adapter has to have a converter that splits the brake lights and turn signals.
American cars use the same light for both turn and stop. Europeans use different ones. The Four pin unit for European cars has a separate converter box built into the unit.
Seems u may have the wrong adapter.

Slow Guy

My current GTS ('10) had what I can only believe was a early model Curt adapter that was stuffed after the original OE Porsche socket and the the end mimicked the Pollak 7 pin round socket, only way I found it was by pulling the socket out and finding it wasn't connected to the plug I thought it was connected to. This caused both incandescent and LED lights to operate weird.

I pulled the Curt connector/adapter out and installed a standard Pollak RV style 7 pin socket, hooked it up to my incandescent trailer and lights worked.

Then connected this adapter and LED lights worked.

User 4221

Nothing to add but just a short rant..... Why do the damn German mfrs make something simple.... Like a trailer connection..... So damn complicated?

It is rhetorical and I fully understand the electrical theory behind the decision, however, it is overkill for this application.

John H

Thanks for the responses. I finally gave up and basically did the following

Installed a flat 7 plug on the trailer. Wired only the ground and running/tail lights.

Ran a wire from the hot brake light wire down behind the bumper cover to the hitch. Put a male plug on the end.

I took the trailer brake light wire and put a female plug on the end of it.

Yes I know it is Appalachian engineering and looks like **** but at least I now can pull the trailer in the dark AND have brake lights. No turn signals on the trailer but what can you do.......

By the way, still have the ! check trailer lights.

If someone would have happened along in the past week and offered me anything reasonable for the truck, I'd have sold it. It really is ridiculous.