Daewoo MATIZ Service Manual page 368

1F – 270 ENGINE CONTROLS
DIAGNOSTIC TROUBLE CODE (DTC) – P1628 IMMOBILIZER NO SUCCESSFUL
Circuit Description
When the ignition switch is turned to ON, the key tested
by immobilizer anti-theft system. While the key code is
being read by immobilizer control unit or integrated anti-
theft control unit, the engine can start 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 control unit. If a valid key is
detected, the immobilizer control unit sends a serial data
release message to the Engine Control Module (ECM).
Included in the release message is an identification (ID)
code which assures that neither the immobilizer control
unit nor the ECM have been substituted to defeat the
system. If the ECM receives an invalid release mes-
sage, the ECM performs the following action:
D Disable the fuel injector circuit.
D Disable the fuel pump circuit.
D Disable the ignition coil.
D A Diagnostic Trouble Code (DTC) will stored if detect
communication link failure between the ECM and im-
mobilizer control unit.
COMMUNICATION
Conditions for Setting the DTC
D Ignition switch is turned to ON.
D Immobilizer option auto detected.
D ECM release time window(1.5 or 2 seconds) expired.
D Vehicle Speed Sensor (VSS) signal is less than 512
km/h.
Action Taken When the DTC Sets
D The Malfunction Indicator Lamp (MIL) will not illumi-
nate.
D The ECM will store conditions which were present
when the DTC was set as Failure Records data only.
D This information will not be stored in the Freeze
Frame data.
Conditions for Clearing the MIL/DTC
D A history DTC will clear after 40 consecutive warm-up
cycles without a fault.
D DTC(s) can be cleared by using the scan tool.
MAA1F330
DAEWOO M-150 BL2