Daewoo MATIZ Service Manual page 1170

9T – 18 IMMOBILIZER ANTI-THEFT SYSTEM
Circuit Description
When the ignition is turned ON, the key is tested by the
immobilizer anti-theft system. While the key code is be-
ing read by the immobilizer control unit, the engine can
start and run with any key that will turn the lock cylinder.
The key code is read and compared with key codes that
have been stored in the memory of the immobilizer con-
trol unit. If a valid key is detected, the immobilizer control
unit sends a serial data release message to the elec-
tronic control module (ECM). Included in the release
message is an identification (ID) code which assures
that neither the immobilizer control unit nor the ECM has
been substituted to defeat the system. If the ECM re-
DIAGNOSTIC TROUBLE CODE (DTC) 1602
ECM IMMOBILIZER ERROR (ECM LOCKED)
ceives an invalid release message, the ECM performs
the following actions:
D Disables the fuel injector circuit.
D Disables the fuel pump circuit.
D Disables the ignition coil.
DTC 1602 Will Set When
D The immobilizer control unit does not learn and store
the codes of valid keys.
DTC 1602 Will Clear When
D The ignition switch is turned OFF or the scan tool
TROUBLE CODE CLEAR command is issued.
D19T002B
DAEWOO M–150 BL2