How does the gen III speed sensor work

[Mattias]

Hi all.
Have been building an AC Cobra replica (based on a viper SRT-10 2006) for some years now. I start to reach the goal now and have some small stuff to clear before it’s ready for inspection. One thing is that I’m using an aftermarket speedometer cluster which operates with a digital 9-32V input for the speed.

My thinking (if I am correct?) is that the stock SRT abs-sensors are used as speed sensors in the viper from gen-3.
If I’m correct, I have also found out that they are fed with 12V in one of the two wires. Meaning they are “active” sensors.?

My question is: “how do they work”? What is supposed to come out through the other wire when riding?

Does anyone has a wiring diagram of the sensor itself? I have the repair manual showing the pinout for the connector (where one wire gets 12V) but it only says signal on the other wire..
if anyone can help me out I would really appreciate it.

Grateful for all input!
Merry Christmas everyone

//Mattias

[Old School]

Yes, you are correct, speed is derived from the abs wheel sensors.

I'm not sure what the signal looks like coming from the sensor. Are you using Viper suspension/spindles in your Cobra?

[Mattias]

Yes, lamors everything is Viper (gearbox, rear axle, suspension, front axle including steering, pedals, tank etc etc).
Due to inspection regulations I have to use a weaker engine to get it approved. However I keep the original engine as a spare in the garage

[Old School]

I have a feeling that "spare" engine will be installed immediately after the vehicle passes inspection.