Aftermarket head unit with parking sensors

Hi, apologies if this question may have been asked before, but I will soon be replacing the head unit in my 2011 Mondeo titanium x sport for a more up to date unit with android auto etc, most likely Kenwood.

I have a query regarding the parking sensors.

I have managed to find a place that can supply the unit, double din fascia panel and the wiring harness at a decent price but I then came across a harness that also has another small loom that comes with a small speaker/buzzer for cars with parking sensors.

I've read on another forum that on some years the parking sensor audible warning came from the head unit and not the speakers so I would need this extra loom and speaker.

Is there a way to tell if I need that extra part of the wiring loom?  I have the Sony single disc DAB head unit with orange illumination, when reversing the "beeps" come from somewhere in the rear of the car and when edging forward the front sensor "beep" sounds like it might be coming from the centre speaker on the dash.

Any help greatly appreciated.