I HAVE A 2004 DISCOVERY 2 when I push the hdc button nothing happens. I changed the switch and it still did not work nothing no lights chimes or anything. Anyone have any thoughts. I have another 03 disco that HDC worked fine in that I can swap parts just seeing if anyone has a good place to start?

 

I know with the Nanocom Evo you can disable the ACE, SLS, and even the HDC lights, however I think it still works. Are you in 4Lo? On a D2 you must be in 4Lo for HDC to operate it will normally just flash a Green Light and beep in 4Hi.

 

I have been 4 low and first gear no lights or beeping that let's me know it is in Hdc mode I am going to try it on a hill today and see if it is working even though it is not showing me it is engaged. I bought this d2 a week ago and noticed the other day the switch was in the on position with no warning signs or sounds so i wonder if it is working. And what to trace down if it is not working.

 

Don't need a hill, just give it some gas and let go, it will come on and you'll feel/hear the crunching sounds of the modulator

 

Does not do anything. I know how it works and what it does. The hdc does not turn on tried going down a hill and nothing the engine brake is the only thing slowing the vehicle. Is there a relay or control unit that operates HDC that I can see if it needs replacing I have a 03 parts vehicle that hdc works on but my newer 04 that I am building it will not engage at all no lights or sounds showing it is engaged. I have already swapped the switch and checked wires behind switch to see If that was the problem. But did not solve

 

Someone could have messed with your cluster & disconnected the speaker. Does your cluster make sound if you leave the lights on or key in the ignition?

 

have you checked fuse 27?

 

Update I checked the speaker on back of instrument cluster and found it missing I hooked up a cluster from my 03 parts care and low and behold I have the 3 amigos pop up. After further look at cluster I took out some person removed led lights from the board instead of fixing 3 amigos properly. I hooked up my scanner and cleared codes in abs and hdc works perfectly. Not I have to change will speed sensors to fix 3 amigos. Is there anything else I need to change if it is showing all kind of sencor readings?