Old 5017 optical sensor wiring

[Macca_75]

Hi all. I have an older 5017 controller. Worked perfect since day 1 - until it didn't....

I've order a new controller.

I'd like to cut both the float and optical sensor off the unit and rewire them for my Profilux (and use it as an alarm for under/over filling). The pinout for the float is easy (just need to confirm if I need a resistor on 1 side or not).

For the old optical sensor (approx 10+ years old) does anyone know what color wire is what? I am assume 2 need to go to DC +ve (hoping it's 12v as the unit is dead and I can't take a reading), 1 would be ground and the forth would be the senor (open/shut circuit based on sensor).

Can anyone confirm the wire colours and if 12v is the required voltage?

Pic is the now dead unit

 

[Macca_75]

@rvitko - would you happen to know what each color wire needs to connect to (12v, GND, Level sensor)? Thanks in advance