badrap

Hello everyone! Sorry that I am writing in english. I don't know spanish. I used google translate to be able to understand these alarm installation instructions. My car is Audi B8.5 MY2012. Based on these instructions I connected only the alarm siren without the buttons and ultrasound sensor. I also activated in VCDS the siren, but when I try to arm the alarm system and lock the door, there is no sound chirp, but the doors close and lights flash as they should. After this I have an error code in convenience module 01134 - Alarm Horn (H12) 008 - Implausible Signal . I bought the alarm siren from a junkyard and it is looking in a very good condition. At first I thought that the batteries inside are bad, but after getting the error code I opened the siren and checked the insides. The insides, PCB and batteries looked fine. They even were charged from the car's battery while they were connected. How to solve this? Please help.