[V8] Seat Heater switches

Sun Feb 1 17:31:29 PST 2015

Nick,

I don't have a schematic handy, nor do I have a vehicle readily available to test, but based upon what you have described, the seat heater switches are very possibly nothing more than potentiometers used to vary a voltage input signal to the relay, and then the relay outputs a varying duty cycled amperage to the seat elements. The sensors in the seat elements are most likely nothing more than bi-metal switches that open to limit max heat.
I'm totally guessing here, but again based upon what you said that would be my SWAG at it (Scientific Wild Ass Guess). :>)
This of course means that the "relay" is more than just a common ISO (International Standards Organization) rectangular 4 or 5 pin relay, but instead has some add circuitry built in ala the intermittent wiper "relay".

Keep us all posted. Butt warmers are a nice feature, in fact within the past week, based upon an email I received from my subscription to Autoweek, I'm planning to use a spare driver's seat from one of the V8 parts cars I had to build a PC Racing Sim Rig, including the power adjustments, with memory and the butt warmers, or bun warmers as some call them.
Many, many moons ago when the very first racing sims came out, I got a steering wheel that attached through a "game port", but soon lost interest as the early sims were pretty unrealistic and therefore pretty boring. That was in the late 1980s. 
Now, holy crap, how things have changed! The email from Autoweek featured the new Ford GT, and the teaser for Forza Motorsport's new sim for XBOX One. I don't own an X Box, and never will, but the point is that after seeing how far current racing sims have come, I'm hooked!
If you think about it, the military has been using them for years to train pilots, and now (probably for some years) top racing teams use sims for their drivers to hone their skills in learn in ng specific tracks.
I found a reasonably priced option for a DIY sim rig with Ricmotech.com 
IMHO it's an easy and cost effective way to give it a shot and not have a big investment in something that you are not sure you'll stick with. For someone like me who cannot currently afford a race car, this is an attractive option that can grow into something bigger and better as desire and funding allow.
The thought of racing others through the online site iracing.com is even more attractive.
I've been flying RC planes on my "Realflight" sim for years, but never gave auto racing sims a second thought due to my experience from years ago. Silly me!
This is going to be interesting!

Sent via the Samsung Galaxy Note® 4, an AT&T 4G LTE smartphone

-------- Original message --------
From: Nicholas Miller <chance9121 at gmail.com> 
Date: 02/01/2015  12:33 PM  (GMT-05:00) 
To: quattro at audifans.com, V8List Fans <v8 at audifans.com> 
Subject: Re: [V8] Seat Heater switches 

This does look like a big endeavour.  I'd like to test at least one switch
and see what the rotary wheel does, vary voltage or current.  I checked my
schematic for at least one set of seats, on my seats the temperature sensor
is in the heater coil, all it gets is 2 wire signal from the switch, and
everything else is sorted in the seat.  I think that may work, but in this
case you would not get more heat, just variability between the current
setting and off, maybe.  Best way to check would be to see what my current
switch puts out for voltage, check inline current on the heater circuit,
then check voltage output on the Audi switch and wire it inline to see if
it varies current when inline.   I think it could work, even though not
like it does in the original system.

Surely, the rotary switch does something with voltage/current even if it
doesn't have the final say in the circuit, correct?  I understand in the
end it seems to just signal a relay that then varies the power/heat level
to the seat in the audi system, so my main question then would be how much
current can the switch carry?  Probably not a ton, in this case.

On Sun, Feb 1, 2015 at 8:27 PM, Nicholas Miller <chance9121 at gmail.com>
wrote:

> I'm in minnesota, 56560
>
> On Sun, Feb 1, 2015 at 1:59 AM, <jlagnese at massed.net> wrote:
>
>> Yes, I have several. I need to check if  they are left and right pairs. I
>> am in Maine. Where are you?
>> John
>>
>> -----Original Message----- From: Nicholas Miller
>> Sent: Saturday, January 31, 2015 4:51 AM
>> To: V8List Fans ; quattro at audifans.com
>> Subject: Seat Heater switches
>>
>> Hey everyone,
>>
>> Does anyone have some pairs of Heated seat switches around?  I want to
>> retrofit a few of my cars with these Audi/vw switches, as I have a 1
>> position button on my heaters for right now.  I'd like to try and retrofit
>> the Audi switch into the car.
>>
>> Has anyone done this before?  I'm not sure if it will work, but in my head
>> it should be simple, I'm assuming its Vin, Gnd, Vout, and Backlight Vin,
>> and the switch operates like a potentiometer.
>>
>> P.s.  The candidates are 2 MX-5s, a Mazda 3, and a Mitsubishi Eclipse.
>> Cause its cold up here in MN.
>>
>> Cheers all,
>> Nick
>> _______________________________________________
>> quattro mailing list
>> http://www.audifans.com/mailman/listinfo/quattro
>> http://www.audifans.com/kb/List_information
>>
>
>
_______________________________________________
Audifans V8 mailing list
Send posts to: mailto:V8 at audifans.com
Manage your list connection: http://www.audifans.com/mailman/listinfo/v8

You can help keep the audifans site running by shopping at http://audifans.com/shop/