CrawDaddy825
Registered User
So my 2011 Audi A3 TDI alarm horn is not working. VCDS fault says "004- No signal/communication". I've read that the batteries are known to go bad and leak acid on the circuits inside the horn. I am looking to replace/repair the horn, but I am not quite sure where it is on my vehicle. Anyone replaced these before? Where is it located?