With your original radio, the sound for the parking sensors came through the radio.
With the satnav radio, the sound for the parking sensors has to come out of separate speakers/buzzers that are nothing to do with the satnav radio.
There are 2 links posted above that show you where these extra speakers/buzzers go, so have a look and see if you already have them fitted to your car. If you do not already have them then you need to buy and fit these separate speakers/buzzers to hear the sound for your parking sensors.
After that you have to use the elm327 cable with elmconfig to tell the car you have a satnav radio so it knows about the extra speakers/buzzers for the parking sensors.
Edited by Mark M, 12 December 2017 - 12:59 PM.