I have this pedals that come with a racing wheel, a PC peripheral, they connect to the wheel and the wheel to the PC via USB, I just want to take the pedals connect them to an arduino board and read their data, leaving out the wheel.
So the cable has 4 wires just like the USB standard, what I did is to apply +5V between the red and black and then connected the meter to the white and green, I was expecting to read some voltage variation as pedals are pressed but nothing happens, it's always 0.
Not enough info.
Do the pedals have a USB plug, or just 4 wires?
It sounds like the steering wheel has the USB interface.
You need to explore and understand what the pedals are sending.
Photo?
Brand? Model? Datasheet?
without this info - who knows.
I figured it out, One of the crocodile clips I was using for the tests was faulty. >:(
Replaced it and now it works just as expected, I get different voltages in a range of +4V / -4V according I press one pedal or the other.