Hi all, wondering if anyone can help please

i have a 2009 A5 3.0TDI Sport,

last driven on friday, went to start it yestarday evening and completely failing to start, obd diagnostics is coming up with gearbox/transmission control module power supply implausable/bad signal and the dash computer is showing Parking Brake failure, once the keyfob is inserted into the dash slot the electrics on the dash/MMI are coming on but thats about it, no attempt to crank what so ever and the gear selector isnt showing that the car is in park, any advice / suggestions welcome thank you in advance. 

When was the battery last renewed?

Hi there, battery was replaced around a year ago following the fuel pump and injector failure.

And was the new battery coded to the car? If not I suggest you get it professionally tested because it may have been damaged and in turn be the cause of false warnings.

See this:

https://www.audiownersclub.com/forums/topic/29630-constant-tone-when-engine-started-but-no-dash-warnings/#comment-124249

 

Hi Cliff, so the battery was replaced by DSR who are local to myself, the bit thats throwing  a spanner in the works is the fact that one moment the car was working as it should be; now all of a sudden these fault codes have appeared and stopped the car from cranking 

That does not answer the question about coding. I have already explained that a defective battery can cause erratic unrelated faults and warnings.

Yeah  I see that now, but also I have been told that  battery coding isnt a thing on this model but will certainly look into it