On Monday it was very intermittent, Tuesday and Wednesday it was constant once speed dropped to below 8mph with totally clear in front. Corner sensors would pick up and flash orange bars down to red on driving close to walls etc, but the red bar across the front without the warning bars. I did think it was a solid red, but today it is more a red/white striped bar (like warning tape).
I did clean the sensors as advised, maybe that's why today has been different but I don't think I can get them any cleaner - it's not that after cleaning they worked properly, just not constantly, which makes me think the sensors haven't failed!
Guess maybe its a visit to the dealer!
Thanks for the help and advice - I will try a clean again on Thursday - and any other recommendations.
ian j