[msford]

UPDATE:

My ACC is still having this issue but I accidentally came across a 'fix' online and I've been using it the past month and it works, literally, 100% of the time.

Which makes me believe that it's a clock spring issue and not a buttons issue. The buttons, imo, and as I've suspected, are fine.

So, I found a suggestion online to give the steering wheel a few punches in as many points of the wheel as possible and keep testing the button until the ACC activates. Sometimes it works on the first punch, sometimes it takes a few or a volley of them. And at various points of the wheel, just randomnly punch and then try pressing the ACC button until the ACC activates.

In the past month it has worked every single time and my ACC activates without fail. Previously I would go on a whole 900km trip from Wollongong to Melbourne without ACC working at all but now I get it working 100% of the time in a matter of minutes. It's a joy to be able to have it back on for the Humy Fwy drive.

Sure, it's not a perfect fix, or a permanent one (I'm guessing that would entail fixing the clock spring issue) but it's certainly a cheap one (a little bit of elbow grease) and, as far as I am aware, no harm done.

Cheers and good luck.