In an attempt to get rid of the 3 Amigos. I have excercised my hill descent control every few weeks. About 1 month ago hilltoppersx was kind enough to read my codes and reset them. I read somewhere that using the HDC can sometimes make the Amigos go away.
I have done this a couple of time and the Amigos have not returned. However, when I engage the HDC and move forward, I hear a buzzing sound like the gears are trying to mesh. If I step on the brakes a couple of times it goes away, buzzing or not, the HDC works. Any body have any thoughts?

 

Matt its not the audible notification from the HDC you are hearing right? Can you take a video of the sound? Where does it sound like its coming from? I think it may be the ABS return pump, especially since you said it stops when you tough the brakes. The HDC is actually using the brakes right? Its not just gearing the engine to slow you down?

 

It is not the audible from HDC. It is definately in the engine compartment, It feels like the HDC is slowing the car down, much more than it does with the car in Low/1st gear. Is the ABS return pump a big issue?

 

First, using the Hill Decent will not make or keep the 3 Amigos at Bay. Second, if your 3 Amigos are off and when using the Hill Decent, you are hearing the ABS unit do exactly what it is supposed to do, activating all the valves in the system to slow you down, makes lots of noise and is normal.
By the way, when did you last do a full 3 pint DOT 4 brake flush, clean brake fluid will keep the ABS a lot happier and your wallet a little less strained.

 

Just got my Disco in June, have not had the chance to do the flush yet. On my list of things to do. Thanks for the heads up on the noise, was a little worried. Knew the urban myth a bout HDC and the # Amigos was too good to be true

 

the sound is the modulator working, you still have the shuttle valve failure and the lights will come back on until its repaired with either a replacement shuttle valve kit or the ground bypass from Josh at USVI. I'm just not sure if your ABS works correctly you might want to try a panic stop from 30mph on dirt and see if the brake pedal pulses. my guess is it won't.

 

I will find some dirt to see what happens. Thanks