Q In your November 2000 issue the Troubleshooting column addressed a problem that has plagued me for months: how to get my factory steering wheel controls to work on my Alpine IVA C800 head unit. You suggested systems from Soundgate and PAC. Unfortunately, their systems only work with a limited set of vehicles (mostly GM, Chrysler, etc.) I have a 2001 Audi A6. Any ideas on a solution?Many thanksGrier Martinvia the Internet
A Thanks for exploring my suggestions! It's nice to know that readers are putting my recommendations into use. The writer of the November letter was the proud owner of a Trans Am and my reply did limit solutions primarily to the Big Three carmakers. I was surprised to find that you as an Audi owner were interested in the modification. I have found that owners of European cars in North America are less likely to try an actual circuit mod to their vehicle. Having gone through about five Volvos over time (the stealth rockets, not the "professor-mobiles") my first reaction was "Doh! I should have thought of that."
You and I are both stuck without an appropriate commercially available device for interfacing easily between our equipment and our vehicles, so I am feeling particularly bad about assuming that I am the only Eurocar owner who wants tweaks.
Here is an additional method that we teach in Mobile Dynamics' "Phase 4" installer training course. Basically, this method involves treading on a couple of warranties so be forewarned that it's your decision.
First thing you need to do is consider the feature set you want to enable between your steering wheel controls and the stereo. If your steering wheel has only a couple of controls such as Volume Up, Volume Down, Track Up, and Track Down then that is all you will be able to control from your steering wheel. The Audi A6 is equipped with six functions in the model that I checked. This is important because you will be modifying the remote control from your stereo to access these six switches. If you have considerably more features on your remote control, then you will be losing all but six of those features. For example, in the case of older Pontiacs, you would have the ability to interface somewhere around 18 functions, which means you would want to choose a stereo that had a fairly complex remote to give you more features.
Gain access to the switches in the steering wheel. The switch assembly may be a simple friction fit mount as in the case of the Pontiac; otherwise some disassembly may be required. Once you get to the terminals on the switches, you will need to use a DMM (digital multimeter) to determine which contacts on the switch complete a circuit when the switch is depressed. Carefully solder wires such as 22 to 26 gauge computer ribbon cable to the two contact terminals of each switch.
Next, disassemble the remote control that came with the stereo, or order a second remote from the parts department. Note where the appropriate switches are positioned on the circuit board inside for the features you want to interface (again, Volume Up, Volume Down, Track Up, and Track Down, etc.) Connect the pairs of wires from the steering wheel switches to the matching contact pads on the stereo's remote control circuit board.
You should now find that whenever you activate a switch on the steering wheel, the remote control transmits the command via the infrared emitter diode on the front of the remote control to the stereo. Remove the emitter diode from the circuit board after you mark down the polarity of the pins.
The next task, which really should have been considered during the planning stage, is to find a location to mount or secure the remote control's circuit board inside the steering wheel somewhere. In many cases there is a cavity that can be made available where the original steering wheel control circuitry once resided.