vandal968

Error:
1517 Trailer hitch control module (AHK) Fault

Keeps coming up and I keep clearing it. Forum search and google search didn't come up with anything. Does anyone know what it means? Why is there even a code for it, the hitch appears to just be a big lump of steel bolted to the back of the car, why would it even need a controller?

cheers,
c

deilenberger

The controller is an interface to the lights and electric brakes on a trailer. It's located in the port side rear compartment behind the panel on the side of the trunk area.

As to why it's needed? Adding circuitry to a circuit that automatically tests for bulb failures (opens and shorts) will make that circuit's operation questionable. The interface avoids that.

vandal968

I didn't find the controller in the driver's side trunk panel, all I see in there is the Park Assist module. Looking closer at the hitch, the metal hitch itself appears to be oem (made in Germany), but was added to the car. The connector is a Pollak and you can see where the bumper cover was cut to accommodate the connector. Also, there is a sticker on the hitch itself saying that the brake controller is not connected.

If someone just spliced-in an aftermarket connector as appears to be the case, then why would the car even be aware of it to give me the AHK fault? I'd like to figure this out, not that I have any plans to tow anything requiring brakes, I'd just like to know what I've got. I did notice a module under the rear passenger seat, I wonder what that is....

dasams

I don't have a good answer but the Bosch electronics were designed before LED lights. I have factory hitch but can't go anywhere without this dongle. The system isn't LED aware and thinks a light is burned out if the lights aren't pulling a big current. For $19, I'd plug one in and see what happens. I have no idea if this will solve your problem but wanted to make you aware. GL.