fault codes

[leekman]

Hi just sorted one problem out on my car Passat 2011 b7 bluemotion se 2.0 and done a diagnostic check to see car ok and found two faults.
1. Comfort, code 470 Data Bus , System in single wire operation.
2. Comfort, code 1134 Alarm horn Fault of alarm horn.
Fault 1. i really could do with some pointers to were to start to look as i have no clue. I am thinking of taking to auto electrician to sort both codes out but would first like some thoughts as to the problem and location .
So when i go to auto electrician i know i will not be paying a exlarge bill .
fault 2. i think that is just the Alarm siren at fault. Does anyone no the location of Alarm siren in 2011 passat est b7 .
Any advice be welcome.