keep an eye on the center display (the little one on the dash), as you park the car you are meant to stop and use D and R until it gets the park right. every time i've used it it's done a perfect job.
This.
Too many drivers are fixated by the larger MyLink screen which distorts space and that makes it easy to for an accidental nudge to occur. The central display shows a proximal slug (similar to nav on HUD) for positioning. No brakes or transmission shift is handled by park assist, only steering, and it will cancel out the moment the steering wheel is turned manually. As much as YouTube vids and enthusiasts would have you believe, the best way to park is the way you were trained to when learning to drive. It's not rocket science and certainly not as if the car can do it quicker or more accurately.
Easy takeaway: In the absence of the rear camera working correctly (which I suspect to be the case), just do the whole park manouvre manually, like we were taught to do when we learnt to drive.
I rarely use park assist; can do the whole shebang far quicker using mirrors, looking around and good old experience. I have observed much earlier on that sloped gutters/chicanes are not receognised by the ultrasonic sensors, either because of the angle of the gutters/chicanes or being lower than standard block gutters. This can result in the wheels rising up onto the footpath. PA also does not know where or if there is something directly beneath the car.
If there has been any panel work done where the ultrasonic sensors are, this should be scrutinised. Panels where damage is proximal to the ultrasonic sensor, or sensor(s), plural, must not be repaired, but the entire panel assembly replaced (Holden have a panel repair advisory about this). Any sensor that may have been jarred can also cause errors. More than 3 thin layers of paint on any one sensor will also dull responsiveness (again, this is detailed in the aforementioned advisory from Holden).
Like HUD displays, sit in a VW (Tiguan, Golf, Tourareg) and you'll see a lot of similarities with PA with the Commodore; I think Holden took its cues from VW (along with Audi) because the similarities of operation and display information are quite striking, right up to the centre display on the instrument panel doing exactly the same thing as Holden's. Holden's solitary camera in lower-spec VFs isn't the full, ideal package — handy for reversing/lining up a trailer, but generally a distracting gimmick that is ubiquitous now. Accidents happen when drivers pay more attention to the display than looking around them like they were trained to do! More cameras (which are also linked to other safety features) are better than just one at the rear.
