0.5
TIME (sec.)
Ignition switch ON
High
Immobilizer
control system
is normal
Immobilizer
control system
is abnormal
Low
0.5 0.5 0.5 0.5
High
Low
8G-4 IMMOBILIZER CONTROL SYSTEM
ON-BOARD DIAGNOSTIC SYSTEM
(SELF-DIAGNOSIS FUNCTION)
Immobilizer Control Module & ECM diagnose troubles which may
occur in the area including the following parts when the ignition
switch is ON.
ECM: D ECM/Immobilizer Immobilizer
Control Module Control
code Module: D Transponder code
D Data link connector D Coil antenna
wire D ECM/Immobilizer
D ECM Control Module
code
D Data link
connector wire
D Immobilizer
Control Module
D Ignition signal
<Vehicle equipped with monitor coupler>
With the diagnosis switch terminal of monitor coupler for ECM not
grounded, the ignition switch turned ON (but the engine at stop) and
regardless of the condition of the engine and emission control sys-
tem, ECM indicates whether a trouble has occurred in the immobi-
lizer control system or not by causing the malfunction indicator lamp
to flash or turn ON.
Malfunction indicator lamp is ON:
No trouble exists in the immobilizer control system.
Malfunction indicator lamp is flashing:
ECM or Immobilizer Control Module has detected some trouble in
the immobilizer control system.
NOTE:
As soon as the ignition switch is turned ON, ECM and Immobi-
lizer Control Module diagnose if a trouble has occurred in the
immobilizer control system. While the diagnosis is being
made, the malfunction indicator lamp stays ON and if the diag-
nosis result is “abnormal”, it immediately changes to flashing
but if the result is “normal”, it remains ON. Diagnosis takes
about 3 seconds at maximum.