How is the factory-installed AHK (trailer hitch) wired?

Okay, as the title suggests, my question is: Do the cables run separately to the front, or are they just attached to the brake lines etc., like the aftermarket kits?

Best regards, WarLord.

Okay, so it seems that in older cars up to the year 2001, only the wiring for the turn signal indicator light runs to the front, and everything else is tapped into from the rear. At least, that's how it works with Audis.

However, starting in 2002, you will need to install a complete wiring harness for the CAN bus.
And you would have to recode the trailer module in the combination instrument, etc. However, you can forget about doing that with VAGcom; you'll need to go directly to a workshop.

Hm, ich hab nämlich nen Passat 3B von 2000, welcher CAN Bus hat. Der hat ne AHK von Westfalia (13 polig) und da ist die Blackbox im Kofferraum. Ich hatte noch keinen Anhänger dran, aber es geht anscheind kein Kabel nach vorne (es wird an die vorhandenen Kabel, welche zu den Lichtern gehen angeklemmt). Von dem her bin ich auch nicht davon überzeugt, dass die Fahrtrichtungsleuchten des Anhängers angezeigt wird (in der MFA). WIs there a way to check if the MFA is correctly configured?

Best regards, WarLord.

If it's not original, it will have a so-called "check control" (or something similar). If the turn signal bulb on the hanger is broken, the entire car will blink faster, just like with a defective vehicle bulb. I think it would be difficult to add a combination instrument warning light later. If anyone has an idea about this, I'm also interested.

The CAN bus your Passat has might be a completely different one.
Just check if your vehicle has a trailer module installed.
It should be installed in the same way as on an A4, specifically on the rear left side. However, it requires a complete replacement of the side panels!

Isn't that great? Probably it won't be long before the sun visor also becomes diagnostic. }