Thanks mate - it does seem to be the cold damp weather, and it may have been low voltage that triggered it but I have had the charger on until 100% and left connected to no avail.
I have found that the connector under the battery for the controle module is the same on various models, A8 4H, A6 etc... and some VWs. So i looked at the pinouts in the current flow diagrams of my A8 and a post 2007 A6 and they are all the same apart from the hall sender pins are redundant (still there on control module end) but just two pin at the caliper end instead of our 4. I woud love to try one of these. On the 2007> A6, they updated the software to be more reliable, better voltage monitoring and algorithms - no longer has hall senders or counts revolutions and no longer has pad wear monitoring. All the pinouts for +, -, pressure switch, cluster lamps, CAN etc etc... are the same.
The Audi A8 4H 2010> is the same too. Hmmm. Could this be a mega upgrade?
The older Q7 and Phaeton had a mechnical pedal instead.
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