Volume Control on HUs, their operation.

[Mikett]

Currently I'm using an OEM head unit as my source. It has a connection to an Dashboard mounted volume control which I treasure for its convenience. I am contemplating changing the OEM to an aftermarket MP3 unit, but would dearly loveto retain the volume control.

I have looked at the OEM unit and the Vol UP and Down is controlled by two momentary lines that short to chassis ground for volume increments.

Has anyone ever looked at the schematics of HU, the volume control circuits and know whether or not I can adapt them to my ondash control? For starters, I would have to look at the units that have a separate vol up and down buttons.

[UrSv]

AFAIK you will have a hard time finding one that can be adapted for that. I would buy one that has a remote control and fit that in your favourite spot.

[SupraGuy]

It'll vary greatly by the aftermarket unit. Some use a direct pot, and that won't be easy to convert, unless it's motorised, and the deck has a remote control.

2 lines shorting to ground sounds like a motorised pot to me, although it could also be for a pushbutton volume control.

Don't buy a deck with adetatchable face. That's going to limit your choices drastically, practiucally all of hte units that I've seen have detatchable faces. The same goes for the "flip face" idea. You need something with the volume control as part of the deck chassis to have any hope at all of wiring in your volume control.

You'll also have to void the warranty and LOOK inside the deck. If it turns out to be impossible, you're stuck with it.

Anything with a pushbutton volume control could be wired in. It might take a couple of relays to make the signal what you want, but at that point it could be done. Similarly a motorized pot could be made to work. (If the deck has a remote control, you ought to be able to do it.)

Note: Depending on the way that the volume circuit is wired, it may be possible to severely damage your head unit. You could have a short circuit in some cases if (for example) you press "volume down" on your control, and "volume up" on the remote or the deck face. Such damage will NOT be covered under warranty (Which you've voided anyway)

Really, the remote control for aftermarket deck is a much easier idea to implement, although it can be done.

UrSv: I fond your comment ironic, considering yoru signature.

[REDSKIN]

Here in the uk most branded hu's have a facility to link into OEM steering wheel controls and displays. I asssumed you'd have them over there. Or am I missing the point when you say mp3 and you're actually trying to link an i-pod or similar to steering wheel controls?

[Mikett]

Most branded ones? interesting. The converse is true in NA. Perhaps you could point out a few models on a web site so I could take a look. Thks.

[rockthisway]

some companies like aamps of america , pie, scosche and some others sell adapters to retain the steering wheel controls with an aftermarket radio. Go to your local audio shop and ask them or go search on-line

http://peripheralelectronics.com/ check here they might have it

hope this helps

[REDSKIN]

Pioneer headunits work with steering controls you need to look for hard wired remote inputs in the hu specs. And if they do alpine and kenwood must surely. Or try www.soundgate.com they seem to have a good selection of adaptors for GM Ford etc.