Nalc,

Thanks for the feedback. No reason not to put in the 100k-ohm resistors just to be safe. Or perhaps I'll put a 200k-ohm resistor across each parallel switch for symmetry...

Interestingly, the resistances seem to step up by 0.5 on a log scale--330, 1000, 3300... Those are readily available at Radio Shack so I went with those.

I did pick up on the short/long press seek/tune, but not Mode/mute. Cool. Good to know.

So the schematic looks okay to you? Glad I'm on the right track.

Yup, seems like it would work fine.

I will buy one

I like this idea a lot. I can't stand the next track/previous track on the touch screen, so I will probably only do one switch for those two. Now to just figure out where I will put that one switch then I will get to work!

And just so I know im understanding everything correctly, if I were to do this I basically would want pin 21 as the input for the switch and pin 23 as the output. When the switch is in the middle position there would be no connection between these pins, in the up position for next track it would create a connection between these two pins with no resistor, and when the switch is pushed down it would create a connection between the two pins with ~330 ohm resistor giving me previous track.

As long as my understanding is correct this seems pretty simple, now I just need to find an on-off-on momentary switch lying around my shop to test it out.

That's correct.

If you have a manual transmission car, I would propose trying to get the three switch traction--snow/sport--stability control module and try to hack it to make the center snow/sport switch serve the seek function.

This is a picture I took of the insides of the TCS switch (MT).

http://i.imgur.com/b2wzssQ.jpg

Sport/Snow are the two gold circles in the center. As you can see, the traces go to the two empty pads towards the right. The MT has 7 of the 9 pads connected - illumination positive, illumination ground, switch common, TCS switch, VSC switch. The AT has the additional 2 pads connected to Sport and Snow.

In theory, if one was to get the AT switch module, you could insert pins into the harness and use snow and sport for alternate functions, but you'd need to make sure that the common contact for all the switches will play nicely with what you're using it for (I do not know whether it's a ground or a positive, or if it will cause problems if you connected it to a radio pin)

I did also observe that it may be possible to jury-rig the MT switches to allow usage of the center switch. The housing and PCB are the same, and the MT center switch blank is installed on a pivot point same as on the AT. The only difference is that the switch blank is so long that it won't freely rock back and forth, and it doesn't have plastic legs that push down on the pads to short out the contacts. It doesn't seem like it'd be all that hard to mod the MT switches so that you could press the center blank and have it do something else (i.e. radar detector mute, radio controls, toggle some lighting, etc)

Nalc,

One more question for you. What's the best way to get the three wires into the 28 pin connector? Are these some sort of standard Molex connector pins?

Thanks again for all the advice.

I couldn't find info on the correct pins, but I found that the pins from a PC motherboard header work fine. If you can get an old computer case, the female pins from the power/reset switch and power/HDD LEDs and the little speaker/buzzer can be used. Just remove them from the black plastic connector they're in. If you don't, I'd pick up a pair of PC internal speakers (the old ~2" paper cone speakers with a 4-pin header that connect to the motherboard and do a beep when you power on your computer) on Ebay and pull the pins from those. USB ports will work, but I've found that the wires in the USB cable are very thin, so I'm concerned about the long-term reliability, and ease of soldering. Again, I'm talking about the pins from the 9-pin connector that goes into the motherboard, not the USB port itself.

For the 28-pin connector, use a very small flathead screwdriver to pry the rectangular insert in the bottom of the connector. Just pop it up a sixteenth of an inch or so , you can't/shouldn't completely remove it. Then you'll be able to slide the pins into the connector from the back, and push the insert back int.

Saving that three way switch for something else.... We will see though Im not sure how good it will come out so I may do this instead.

I'm done!
 

Success!!! I finally got around to finishing this project. I am delighted with how well it works. Thanks, Nalc, for the guidance.

I ended up buying a new center console so it could hack it up offline. I alb wanted to start with a console without the heater switch cutouts so I could leave as much material as possible t reinforce the button panel, which is fairly thin. I did a bit of a hack job to cut the holes frothy sbitches, but it doesn't matter as they art covered. I took a picture of the underside with the resistors soldered onto the switches. Sorry I didn't take a picture of the wiring harness attached. Basically I used three 22awg stranded wire and attached the with spade quick disconnects (3/16" fits the switches).

Relocating the seat heater switches to the center storage worked out pretty well (took a hell of a lot of time though filing the hole just right). They're slightly loose cause the stock material quite thick enough for the switches. I installed the armrest at the same time so the heater switches are tucked away out of sight.

The switches fall right where my hand naturally rests with my arm on the armrest. I am fairly tall so ye might be a bit far back for some.

Happy to advise if anyone wants to replicate.

Attachment 56844

Here's the final setup.

Not terribly exciting, but here it is in action.

[ame="http://youtu.be/zoyg30JZJec"]http://youtu.be/zoyg30JZJec[/ame]

Haven't tried the phone control yet. Phone wasn't in my pocket...

I can't make out the radio clearly. Is that the same one in the anniversary FR-S?
This is a great idea.

It's the stock BRZ Fujitsu Ten, which is quite different from the Pioneer FR-S head units in it's inner workings.