The component you are looking for is technically the (Part No. Typically: A 210 820 05 26 or A 202 820 05 26). Primary Location The alarm module is located inside the engine bay, on the passenger side (Right-Hand Drive vehicles: Left side).
Vehicle Platform: Mercedes-Benz W210 (E320, E430, E55 AMG, E300 Diesel, etc.) Model Years: 1996 – 2002 Subject: Location of the Anti-Theft Alarm (ATA) Siren Module Overview The W210 is equipped with an Anti-Theft Alarm system (ATA). Unlike modern cars where the siren is often buried behind a wheel well liner, the W210 places the unit in an exposed (yet concealed) location prone to water ingress and battery failure. w210 alarm module location