OEM Hitch Trailer Plug Question

[FlakoRevoS4]

So i installed the OEM hitch and wiring on my 2018 sq5, i got the module coded at the dealer and the activation worked, but I am testing the 7-way connector with a 7-WAY RV BLADE CONNECTOR TESTER #58270 and i am not sure is the connector is working or getting any kind of signal or if this curt tester is not drawing enough or faulty. i attached a link to a video i took, lights on the tester flash with the car on and off. maybe someone here can help me

Video: https://imgur.com/a/OMuPOx5

[Smac770]

Hard to guess. All the documentation I find discusses a 13-pin connector. You'd need a wiring diagram to explain which pins on the towing control module are connected to which pins on the 7-pin connector to guess at what you should expect on those pins. You'd need VCDS or such to scan to see if there's any codes. Basically, Audi has no documentation of the wiring for that 7-pin connector, so no idea what should be what on it.

[FlakoRevoS4]

i did one yesterday and no codes this is what I found in regards to the 7-pin layout on the audi plug, which it doesnt add up now that I look at it, when I compare the
configuration from the installation manual to the actual plug layout

[Smac770]

The image on the flap is not the same as the Audi image. https://www.curtmfg.com/towing-electrical-wiring - it doesn't appear the Audi pin arrangement is either 7-pin RV blade configuration.

The connections are just straight through on the socket: https://www.ecstuning.com/b-genuine-.../pna95511893b/

I don't have a new enough B9 Q5 wiring diagrams document (ie, the one on cardiagn) to have the US spec trailer socket wiring. But for the B8 Q5 (which is probably the same configuration), we see:

1 - left brake/turn light - black/white back to J345
2 - ground - brown back to vehicle chassis
3 - blue to apparently this is connected to pin 4 on some 4-pin plug?
4 - right brake/turn light - black/green back to J345
5 - 12v - red/green back to J345
6 - tail lights - gray/red back to J345
7 - reverse lights - white/blue back to J345

(J345 = the towing control module which you had them install into the vehicle)


I'd probably start with a voltmeter on the battery positive and check until you find where ground is (get a 12v reading). Then put the meter on that ground and test if any have 12v active with no lights/brakes active. That should be 2 pins clockwise from ground according to the Audi image. But should be opposite the ground according to the Curt images of standard and SAE 7-blade RV connections. Then test with tail lights on, brake lights on, turn signals on, figure out what is where. Then you can decide if you need to move things around on the car side of the Pollack socket to meet whatever you're plugging into it.