Passat 3C automatic tailgate and trailer operation

Hello, I used the search function, but unfortunately, I couldn't find anything.

Is it possible to program the automatic tailgate of a Passat 3C so that it also opens automatically when a trailer is attached?

I know that it's a safety feature from VW, but with Audi models, it's possible to open the tailgate even when a trailer is attached.

Chassis number: WVWZZZ3CZCE122788. Year of manufacture: 2012.

I would be very grateful for a response.

Sincerely,

Hello,

The functionality is usually configured via the coding of control unit address 46, but I am not aware of any coding options to differentiate between vehicles with and without a trailer.
Rear hatch soft-touch feature in byte 1 of the long encoding.

If the tailgate is very difficult to open manually when a trailer is attached (without hitting something), it might be possible to simulate the trailer detection system (trailer socket) in this case.

Best regards, Rainer.

dieselschrauber wrote:

If the tailgate with a trailer is very difficult to open manually (without hitting something), it might be possible to fake the trailer detection (trailer socket) in this case.

Hi Rainer,

"How does that work? The AHK (trailer hitch) socket no longer has a mechanical switch that determines whether a trailer is connected or not. Instead, the detection is done through the diagnosis of the trailer lights. As soon as the AHK control unit detects that trailer lights are connected, it reports "trailer - yes" (through a specific data block, likely in areas 69 and 03)." I suspect that this information will automatically disable the electronic tailgate and switch the ESP to trailer stabilization mode.

And precisely because of the latter, I wouldn't want to start with the AHK control unit, but only with the electric flap control unit. However, I'm not aware of any way to circumvent this, but (my brother) would also be interested in finding a solution.

PS: When a Thule bike rack is installed, it's crucial to remember it's there...

Greetings.
Guste.

Hello Guste,

You can, of course, wire the trailer lights yourself; to do this, you need to disconnect the existing connection at the trailer socket. It would work regardless of whether the trailer detection is implemented via a switch or power detection.
The amount of effort it requires and whether it's worth it are separate issues.

Since I don't have an electric trunk release (and after researching the topic, as well as knowing that an acquaintance often has to drive off with the trunk open in the mornings because it malfunctions, I definitely won't be buying one), everyone has to decide for themselves whether the effort is worth it.
Ultimately, it also depends on how often the described "comfort accident" occurs, whether it's once a year or every week.

Best regards, Rainer.

Hello, I happened to see a Sharan 2 parked outside my door yesterday, and it had a tow hitch and an automatic tailgate. I then went into the tailgate control unit for long coding, and lo and behold: it works!

You can uncheck the box in byte 4, and the tailgate will automatically open when a trailer is connected (with the 13-pin connector plugged in).
Since the pin configuration can be changed in byte 1, I assume that this control unit is installed in the following vehicles: Porsche Cayenne, Skoda Superb, Octavia, VW Sharan, and Seat Alhambra.
I've attached a scan of the control unit and a photo of the coding.
Perhaps this is suitable for the section "Instructions".

Sincerely,


Address 6D: Rear hatch (----)
Label file: RKS\7N0-959-107.clb
Part number SW: 7N0 959 107 B, HW: 7N0 959 107 A.
Component: HDSG Module H11 0803
Revision: 41011001 Serial Number: 149100132
Encoding: 0733334002
Operating Number: WSC 00020 999 12345
ASAM Dataset: EV_HDSGVW428 201133
ROD: EV_HDSGVW428.rod
VCID: 366898BC895B39AE711-8063

No error codes found.