Red brake light and abs light

[Audi-paddy]

Hi
I have an a4 b6 avant 54 reg 1.9tdi sport
I have recently noticed with the cold weather when I start the car I get a red light saying brakes and then abs light on, happens mainly when it's been cold, but started randomly doing it but only on start-up
Battery was fully charged a few days ago, brake fluid is full
Scan shows
65535 internal control module memory error 00-00
18057 powertrain data bus P1649 35-00 missing message from abs controller

Any ideas
Thanks

 

[Audi-paddy]

Anyone?

 

[Mike B]

My 2.5tdi does it mainly in cold weather.I think its the sensor under the fluid reservoir that gets triggered by the current and its not easy to fix

 

[Dibs_h]

Battery is on it's way out mate. I had the exact same issue some years ago & changed the battery and never had the issue again.