Steering Wheel Controls

**Izik** · 05-18-2004, 04:12 PM

Did you connect it to a game port on a sound card or motherboard or are you using a usb converter?

**god_of_cpu** · 05-18-2004, 04:33 PM

Originally Posted by Curiosity

What's with the "Power" on the left? It already has +5V on it, so if you disconnected that it seems like it would work better. I'm assuming it's +12V from the car?

The power on the left is actually for the line on the steering wheel that accepts the +5v power from the game port and is routed through the steering wheel controls and output to the lines for it... it's recieving power not supplying. If you disconnect it, it definitly won't work.

**god_of_cpu** · 05-18-2004, 04:41 PM

Lorenzo,

Your diagram looks good and if your getting those resistance values from your steering wheel controls, your car should be compatible. However, as Izik said, the problem may lie in your game port. Apparently the USB adaptors may not be able to detect the resistance at the ohm level. I have neither confirmed nor denied this myself though. If possible, I would suggest trying a PCI based sound card with a game port as it's the only thing that I have confirmed works at the ohm level.

**god_of_cpu** · 05-18-2004, 04:58 PM

It *may* be possible to get a USB game port adaptor to work if you first build the voltage to current converter circuit found at the bottom of this page, but this is just a guess.

**vicky_obee** · 08-24-2004, 11:23 AM

Hi well this looks pretty impressive. and well just wanted to know will this SWC work on all cars that have a control on steering wheel. Like the SKODA.. and is it still on test phase or fully working.. If its owrking i am willing to pick it up if u ship it to INDIA

**god_of_cpu** · 08-24-2004, 11:41 AM

The only cars it will work on are those that communicate by varying current when a button is pressed on a steering wheel. This should include most, if not all them listed in the SWI-X PDF file linked earlier in this thread. I can't say anything about cars not in the PDF. The way to confirm any car is just take a voltmeter to the control lines in your car and see what happens to the resistance when you connect it up.

There is also nothing to buy from me. All you need to do this is a couple standard resistors and diodes and some wire. It doesn't require any ICs as I originally thought it might. You should be able to get all the parts you need from radio shack or someplace like that for < $5.

**DjBac** · 09-03-2004, 04:36 PM

I tried to use my car's steering wheel controls..
But i have a problem...

it has 4 wires.. ACC,GROUND,TX+ and TX-.
I connect +12v to ACC ground to GROUND and then check volts to TX+ and TX-..
But the volts don't change!!
Either 2,5 and 12V...
Am I doing something wrong??

**frodobaggins** · 09-03-2004, 09:31 PM

Originally Posted by DjBac

I tried to use my car's steering wheel controls..
But i have a problem...

it has 4 wires.. ACC,GROUND,TX+ and TX-.
I connect +12v to ACC ground to GROUND and then check volts to TX+ and TX-..
But the volts don't change!!
Either 2,5 and 12V...
Am I doing something wrong??

Sounds like you have digital controls.

**CHUPACABRA** · 09-03-2004, 09:42 PM

I just use the vol,track and scrol wheel off my logitech keyboard attached to my wheel.

**MSUC5Vette** · 09-04-2004, 12:00 AM

Originally Posted by god_of_cpu

Heres the circuit diagram without the relay.

If you have more then 2 wires for your controls, you will just need to add a resistor and diode for each additional wire and hook it up in a similar way. You will be limted to 4 wires since the joystick port only supports up to 4 axises.

Also, the diagram states a 500 ohm resistor, but this is not set in stone. You may have to use something other then a 500 ohm resistor to get the best voltage values, but probably anything from 10 ohm = 1k ohm will work at some level.

Would it be possible to use a double pole switch with one pole through the 500 and the other through the 1K to double the number of buttons you can use?