Suzuki WagonR+ RB310 Service Manual page 2940

DIAGNOSIS
ECM and immobilizer control module have on-board diagnostic
system. Investigate where the trouble is by referring to DIAGNOS-
TIC FLOW TABLE and DIAGNOSTIC TROUBLE CODE TABLE.
PRECAUTIONS IN DIAGNOSING TROUBLES
D Before confirming diagnostic trouble code, do not disconnect
connector from ECM, battery cable from battery, ground wire har-
ness or main fuse.
Such disconnection will erase memorized information in ECM.
D For non-EC spec vehicle (equipped with diagnosis connector #3)
If abnormality or malfunction lies in two or more areas, MIL (mal-
function indicator lamp) indicates applicable codes three times
each.
And flashing of these codes is repeated as long as diagnosis ter-
minal is grounded and ignition switch is held at ON position.
When ECM detects a trouble in both electronic fuel injection sys-
tem and immobilizer control system, MIL indicates trouble codes
of both systems alternately while ignition switch is turned to ON
position and diagnosis terminal is grounded.
D Diagnostic trouble code stored in immobilizer control module
memory can be cleared as well as checked by using SUZUKI
scan tool. Before using scan tool, read its Operator's (Instruction)
Manual. Carefully to have good understanding as to what func-
tions are available and how to use it.
D Be sure to read PRECAUTIONS FOR ELECTRICAL CIRCUIT
SERVICE in section 0A before inspection and observe what is
written there.
D There are cases where MIL indicates a DTC that occurred only
temporarily and has gone. In such case, it may occur that good
parts are replaced unnecessarily. To prevent such case, be sure
to follow instructions given below when checking by using DIAG-
NOSTIC FLOW TABLE.
D When trouble can be identified, it is not an intermittent one:
check ignition key, wires and each connector and if they are all
in good condition, substitute a known-good ECM and recheck.
D When trouble can not be identified but MIL indicates a trouble
code: diagnosis troubles by using that codes No. and if ignition
key, wires and each connection are all in good condition, turn
OFF ignition switch and then ON.
Then check what MIL indicates.
Only when they indicate trouble code again, substitute a
known-good ECM or immobilizer control module and check
again.
If they indicate not DTC but normal code, it means that an inter-
mittent trouble did occur and has gone. In this case, check wires
and connection carefully.
IMMOBILIZER CONTROL SYSTEM 8G-5