Parking sensors advice please?

[hsyben]

2003 E85 2.5i

I bought this car with an aftermarket parking camera fitted - it seems to have been a wireless device since I found a small receiver. I have now stripped it out but have also lost any sound from the parking sensors.

My questions....
Would the audible sensors have been connected to the camera? Or would the sensors (photos attached) have been factory fitted and I have blown a fuse?
Would it be a major expense to get them replaced?
Thanks
Any advice would be most welcome.

 

[Rockhopper]

Did you ever get any sounds?

 

[hsyben]

Yup. Worked fine.
Not checked fuse 8 yet - fingers crossed

 

[hsyben]

Ok. The fuse card suggests that fuse F8 runs the parking sensors but that is fine. Could I have aftermarket sensors and, if so, can I get new sensors installed? Do they connect to the radio or where does the sound come from?