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EWS
EWS III (3.2)
The 1997 Model Year E38is equipped with EWS III (3.2) drive away protection. E39vehi-
cles produced 3/97and later are also equipped with EWS III (3.2).
Purpose of the System
The major changes of the EWS III (3.2) system over the EWS II are a modified control mod-
ule, revised wiring and the addition of the clutch switch input.
Output functions, starter control and ISN signal, remain the same for EWS III (3.2).
Component changes are:
• EWS III (3.2) Control Module.
• Input From The K-Bus.
• Clutch Switch.
• Transmitter/Receiver Module Eliminated.
System Components
EWS III (3.2) Control Module
The EWS III (3.2) Control Module has a 13 pin connector. The transmitter/receiver module
is no longer a separate module of the system with the electronic functions for the data
transfer between the key transponder and the EWS control module being handled directly
by the EWS III (3.2) control module. The vehicle wiring harness has been changed to reflect
this modification and to route the wiring from the ring antenna directly to the EWS III (3.2)
control module.
Input From The K-Bus
Reduction in wiring has also been accomplished with the use of the K-Bus for data com-
munication between the GM, Door Module, IKE and the EWS III (3.2) control module. This
data link provides the following signals to be communicated on one wire:
• Engine Speed.
• Lock and Unlock Requests.
• Code Function.
• Range Selector Position (Redundant Signal).
Engine Speed
The DME outputs the engine speed “TD” signal over the CAN Bus to the IKE. The IKE uses
the TD information as needed and passes it on to the EWS III (3.2) via the K-Bus.
