Thread: HDC and Trailer Brakes

Originally Posted by veebs

Does anyone know with certainty if a correct installation of a trailer brake controller would activate the trailer brakes when using hill descent control?

Our D4 had a red arc unit installed when we bought it, and it applies the brakes as expected when driving on road, however I noticed nothing happened back there when using HDC on a steep track. Confirmed, by pressing the foot brake mid way, and feeling the trailer pull up.

I’ve never bothered checking the wiring because it works on road just fine, and I live by the ‘if it ain’t broke, don’t fix it’ mantra :-)

It should do as the brake lights operate when HDC is active (I tested this once).

I think it does Veebs , the operative word is ‘ think’ , however on some steep descents I just use the button on the redarc and rely more on the van brakes.

Must add this is on dirt or gravel tracks

dave

If the brake controller is wired to the D4 brake lights then yes it will activate the trailer brakes when HDC applies the D4 brakes. At least it does with my MY14 D4, it also worked the same way with my MY03 D2.

Hdc is LOTs of small pulses, to get the trailer to assist more - wind up the redarc controller