The New Drive Authorization System

As of Model Year 1997, the Drive Authorization System version 2 (DAS-2) known from Model Year 1996 (refer to SI MBNA 80/06) is further refined.

DAS 2a





In the brief time period between the start of E420 (model 210.027) production (01/96) and the beginning of main series production for Model Year 1997 (06/96), an interim system, known as DAS-2a, is installed in E420 vehicles. This system is identified by the presence of a transponder ring (L11, Figure 1) around the ignition lock and the absence of exterior IR receivers

DAS X
As of Model Year 1997 (06/96 production), all models are equipped with an updated Drive Authorization System, known as DAS X. This system incorporates the vehicle security features of DAS-2a with the convenience of exterior IRCL sensors. This system is identified by the presence of exterior IR receivers and a transponder ring (L11, Figure 1) around the ignition lock.

Important features:
^ IRCL (vehicle locking) and DAS (engine disablement) functions are separated: The locked or unlocked condition of the vehicle no longer affects the ability of the engine to start.

^ The IR and mechanical door/trunk lock portions of the system control the Central Locking (CL), Convenience Feature (CF) and Anti-Theft Alarm (ATA) systems.

^ The new transponder system controls engine start authorization.

^ The DAS X system uses two control modules: an IRCL module and a DAS module. DAS-2a uses only one module.





^ The DAS X system has three IR sensors, whose location depends on model (Figure 3). The DAS2a system has only one IR sensor, located in the interior rearview mirror.

Spare parts:
As before, the DAS 2, 2a and X control modules must be coded for a specific VIN. In addition, with DAS versions 2a and X, all keys (including mechanical keys) contain transponders, and thus must be coded to the VIN.

For DAS-2a and X, a maximum of eight (8) keys (both IR plus mechanical) may exist for a given vehicle. Since four are provided with the vehicle when new, up to four additional keys may be ordered via Spare Parts. However, each key transponder is unique, so if a key is lost, it can be replaced with another key with the same key "number" (1 to 8).





It is not possible to have two keys with the same key "number" - one will be automatically disabled by the control module. Supplied with the vehicle are two IR transmitter keys (1, Figure 2), one flat (mechanical) key (2, Figure 2) and one round-head valet key (mechanical key) (3, Figure 2). A mechanical master key is not available as a spare part, although the flat key has all the functions of a mechanical master key, without the large square head.

Components:
DAS-2a consists of the following components:

^ IR transmitter (remote key)
^ IR receiver (at interior rearview mirror)
^ Mechanical switches (at driver's door and trunk locks)
^ Transponder chip (embedded in each key)
^ DAS control module (located behind instrument cluster)
^ Electrical coil surrounding ignition lock (L11, Figure 1).
^ Flasher Relay (CCM)
^ Engine control module

DAS X has these additional components:

^ Two additional IR receivers (total of 3 - location depends on model)
^ IRCL control module

Control Module Locations:
In all vehicles, the DAS control module is located behind the instrument cluster. Note that the transponder ring wiring is limited to 500 mm in length. The location of the IRCL control module is the same as in previous systems: 202 and 210 - passenger's footwell; 129 - right side of trunk; 140 - under right front dash

Lock and Sensor Arrangement:

With the introduction of the DAS X system, the arrangement of locks on the front doors is changed. With DAS-2, introduced in all models as of MY'96, the lock cylinder on the passengers door was removed, leaving a lock cylinder on the driver's door and the trunk. Additionally, only a single IR sensor, located in the interior rearview mirror, was used. This remained the same with DAS-2a.

In models 129 and 140, the lock arrangement has not changed with DAS X: Both the driver's door and the trunk have fully4unctional lock cylinders. However, the IR sensor in the interior rearview mirror is deleted, and replaced by three exterior IR sensors, one located in each front door and one at the trunk. This is similar to the arrangement in MY '95 vehicles.





Lock and Sensor Arrangement - Table

In models 202 and 210, only the passenger's door and trunk have lock cylinders - there is no lock cylinder on the driver's door. The IR sensor in the interior rearview mirror remains, and is supplemented by two exterior sensors, one located in the driver's door and one at the trunk.





Block Diagram - DAS-2a:





Block Diagram - DAS X: