Alarm system Spint

Hello colleagues, with my 2004 SL 600 the alarm system spins for about 1 week. Will the car be closed after 5 minutes at the latest the alarm starts. iCarsoft shows as error B1341 “Communication error with component H3 (alarm signal horn)”. Does anyone know what to do? And or an SL specialist in the Cologne area, like up to 300 km radius that can help me further? Oh so, any fun recorder with suggestions like, buy a new diagnostic device please do not report at all. Al I would like to thank the serious commentators for their feedback.