Technical How Fiat A-BUS for rain sensor works?

[anyzunstudios]

Hello, I am trying to make the rain sensor work using an Arduino. As far as I know, the rain sensor is the only sensor that has it's own protocol, called A-BUS. I am trying to power up the sensor using a 12v power supply from an old PC, and when it connect it to +12v, the sensor turns on for a second and then it turns off again. It seems that sensor works, because using a Phone camera you can see IR LEDs powering up and then turning them off. I don't know if A-BUS send a PWM pulse making the sensor turn on and off "X" times/sec, and it A-BUS is an analog or digital protocol.

Sensor has 3 pins, +12v, GND, and Signal.

Can somebody help me with it?

Thanks!

 

[Bernievarian]

Hola Julio,

since this sensor got a power supply I'd suspect it to have internal electronics to measure the IR reflection that would be modified by rain drops on the windshield. Probably analog signal; can't you simply probe the signal with a DMM or a scope ?

BRs, Bernie