Deactivating anti-theft alarm (ATA), function

P80.50-2025-06

Illustrated on vehicle with interior motion sensor (IMS) code 882

A26/14 Interior motion sensor transmitter and receiver

H3/1 Alarm siren with auxiliary battery

N10/6 Left front SAM control module

N10/7 Right front SAM control module

N10/8 Rear SAM control module

N70 Overhead control panel control module

N72/1 Upper control panel control module

N72/1s7 TS, IMS, and ATA function indicator switch

N73 EIS control module

The anti-theft alarm (ATA) is deactivated when:

 The vehicle is unlocked with the remote control key

 The vehicle is unlocked by opening one of the front doors from inside (possible up to max. 10 seconds after locking with the remote control key)

 The vehicle is centrally unlocked with the lock switches
(model 220 ,  only)

 The vehicle is unlocked with the KEYLESS GO feature
(code 889 only)

 The remote control key is inserted into the EIS control module (N73) if the vehicle was previously locked with the remote control key.

The ATA is not activated when the vehicle is unlocked

 with the interior central locking switch (N72/1s6) or

 with the emergency unlocking feature.

Function sequence
The EIS control module (N73) transmits the command to centrally unlock the vehicle on the CAN bus. The left front SAM control module (N10/6) deletes the message "ATA active" on the CAN bus. The corresponding control modules deactivate the alarm inputs.

 only:
The alarm signal siren with additional battery (H3/1) buzzes momentarily once when the ATA is deactivated.

Moreover,

 the left front SAM control module (N10/6) deactivates the alarm signal siren with additional battery (H3/1).

 the overhead control panel control module (N70) deactivates the interior motion sensor (IMS), if connected and activated.

Partially deactivating the ATA with remote trunk release (RTR)
When the trunk lid is opened with the remote control key the TS and IMS are deactivated:
The left front SAM control module (N10/6) receives the CAN message from the EIS control module (N73) and transmits the commands to the corresponding control modules to deactivate the TS and IMS.

After closing the trunk lid the left front SAM control module (N10/6) causes the ATA to be reactivated. TS and IMS are only activated if they were activated before the trunk lid was opened.

 Deactivation of the ATA interrupts a previously triggered alarm.