Suzuki GA413, Service Manual

Page: 965 / 1246

8G-6 IMMOBILIZER CONTROL SYSTEM (IF EQUIPPED)
GA413
supple
DIAGNOSIS
PRECAUTIONS IN DIAGNOSING TROUBLES
PRECAUTIONS IN IDENTIFYING DIAGNOSTIC TROUBLE CODE
ECM
Before identifying diagnostic trouble code indicated by malfunction indicator lamp or Suzuki scan tool, don’t dis-
connect couplers from ECM, battery cable from battery, ECM ground wire harness from engine.
Such disconnection will clear trouble codes for engine and emission control system and immobilizer control sys-
tem stored in memory of ECM.
If abnormality or malfunction lies in two or more areas, malfunction indicator lamp indicates applicable codes
three times each.
And flashing of these codes is repeated as long as diagnosis terminal is grounded and ignition switch is held
at ON position.
When ECM detects a trouble in both engine and emission control system and immobilizer control system, mal-
function indicator lamp indicates trouble codes of both systems alternately while the ignition switch is turned ON
and the diagnosis terminal is grounded.
Take a note of diagnostic trouble code indicated first.
Immobilizer Control Module
Before identifying diagnostic trouble code indicated by analog type voltmeter, do not disconnect couplers from
immobilizer control module, battery cable from battery and/or immobilizer control module ground wire harness
from engine.
Such disconnection will clear trouble codes stored in memory of immobilizer control module.
Take a note of diagnostic trouble code indicated first.
INTERMITTENT TROUBLES
There are cases where output of diagnostic output terminal, malfunction indicator lamp and/or Suzuki scan tool
indicate a diagnostic trouble code representing a trouble which occurred only temporarily and has gone. In such
case, it may occur that good parts are replaced unnecessarily. To prevent such accident, be sure to follow
instructions given below when checking by using “Diagnostic Flow Table”.
* When trouble can be identified, it is not an intermittent one:
Check coil antenna, ignition key, wires and each connection and if they are all in good condition, substitute
a known-good ECM and recheck.
* When trouble can not be identified but output of diagnostic output terminal, malfunction indicator lamp and/or
Suzuki scan tool indicate a trouble code:
Diagnose trouble by using that code No. and if ignition key, coil antenna, wires and each connection are all
in good condition, turn OFF ignition switch and then ON.
Then check what malfunction indicator lamp, output of diagnostic output terminal and/or Suzuki scan tool indicate.
Only when they indicate trouble code again, substitute a known-good ECM or Immobilizer Control Module and
check again.
If they indicate not trouble code but normal code, it means that an intermittent trouble did occur and has gone. In
this case, check wires and connections carefully again.