EWS III (3.3) system.

System Components

EWS III (3.3) Control Module:
The EWS III (3.3) Control Module uses the same 13 pin connector as EWS III (3.2) but functions differently. The EWS III (3.3) module has a “Rolling Code” ISN assigned to it during manufacture. The (Rolling Code) is burned into the module and cannot be overwritten by ZCS Coding or DME alignment procedures.
The (Rolling Code) is a one way signal from the EWS III (3.3) control module to the DME and is similar in operation to the data exchange between the EWS control module and the key transponder.
The (Rolling Code) will be different each time the start operation is begun. The (Codes) are taken from the (Rolling Code Table) which is assigned at the factory to the EWS III (3.3) control module and the DME.

DME Control Module:
The DME Control Module has changed in that it is not the source of the ISN but now only stores the (Rolling Code). It compares the (Codes) to those sent to it by the EWS III (3.3) control module. The (Rolling Code Table) assigned to the DME must match the table in the EWS III (3.3) module. The Rolling Code Table is (burned) into the DME during the programming of the DME and cannot be change once “burned”.

Transmission Range Selection Input:
With the introduction of the SKE type connectors on Transmission Control Modules the direct input from the Transmission Range Selector Switch is eliminated. The input for range selection is now received from the AGS Control Module.
On manual transmission vehicles clutch status is input directly into the DME.
 

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