7
EWS
• 4 cylinder =1800 RPM
• 6 or 12 cylinder =1200 RPM
• 8 cylinder      =900 RPM
The  relay  contacts  will  close  when  the  exceeded  Hz  value  drops  to  5Hz  below  the  maxi-
mum value. This is intended as a safety feature to prevent starter motor activation when the
engine is running above these speeds.
Output
The DME receives a High/Low signal from the Starter Immobilization Relay. When the sig-
nal is High, the DME does not activate injector or ignition operation.
DWA (E31)
The DWA outputs a High/Low signal to the Starter Immobilization Relay indicating the con-
dition of the alarm system.  A High signal indicates the alarm is armed, preventing vehicle
starting.
Principle of Operation
The EWS Starter Immobilization Relay receives it’s inputs from the Ignition switch,  GM (or
DWA),  BC,  Trans  Range  Switch  and  the  DME  (after  6/94).  The  relay  will  prevent  engine
starting if:
•  The vehicle is locked from the outside. The GM receives the High signal from the 
door lock switch and sends a High signal to the EWS. 
• The BC Code function is set.
• A DWA High signal is received. (E31only)
• A Low signal is received from the Trans Range Switch.
• The engine speed signal from the DME exceeds 60Hz. (after 6/94)
The  Ignition  and  injection  functions  of  the  DME  are  disabled  and  the  KL50  start  signal  to
the starter is opened to prevent starter operation.
Workshop Hints:
Starter  Immobilization  Relays  are  different  for  manual  and  automatic  vehicles,  check  to  ensure  correct
relay is installed.
The Starter Immobilization Relay is not on the Diagnostic Link. Conventional troubleshooting techniques
using the DISplus, a DVOM and the correct ETM are necessary.
Loss of input from the GM or BC will allow the engine to start.
Loss of input from the Trans Range Switch will NOTallow the engine to start.