Suzuki SWIFT RS415 2017, Service Manual

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Engine General Information and Diagnosis: 1A-1
Engine General Information and Diagnosis
Precautions
Precautions on Engine Service
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CAUTION:
The following information on engine service
should be noted carefully, as it is important in
preventing damage, and in contributing to
reliable engine performance.
• When raising or supporting engine for any reason, do
not use a jack under oil pan. Due to small clearance
between oil pan and oil pump strainer, jacking against
oil pan may cause it to be bent against strainer,
resulting in damaged oil pick-up unit.
• It should be kept in mind, while working on engine,
that 12-volt electrical system is capable of violent and
damaging short circuits.
When performing any work where electrical terminals
can be grounded, ground cable of the battery should
be disconnected at battery.
• Any time the air cleaner, throttle body or intake
manifold is removed, the intake opening should be
covered. This will protect against accidental entrance
of foreign material which could follow intake passage
into cylinder and cause extensive damage when
engine is started.
Precautions in Diagnosing Trouble
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• Don’t disconnect couplers from ECM, battery cable
from battery, ECM ground wire harness from engine
or main fuse before confirming diagnostic information
(DTC, freeze frame data, etc.) stored in ECM memory.
Such disconnection will erase memorized information
in ECM memory.
• Diagnostic information stored in ECM memory can be
cleared as well as checked by using SUZUKI scan
tool or OBD generic scan tool. Before using scan tool,
read its Operator’s (Instruction) Manual carefully to
have good understanding as to what functions are
available and how to use it.
It is indistinguishable which module turns on MIL
because not only ECM but also TCM turns on MIL
(For details of on-board diagnostic system for A/T,
refer to “On-Board Diagnostic System Description: in
Section 5A”). Therefore, check both ECM and TCM
for DTC when MIL lights on.
When checking ECM for DTC, keep in mind that DTC
is displayed on the scan tool as follows depending on
the scan tool used.
– SUZUKI scan tool displays DTC detected by ECM.
– OBD-II generic scan tool displays DTC detected by
each of ECM and TCM simultaneously.
• Priorities for diagnosing troubles
If two or more DTCs are stored, proceed to the DTC
flow which has been detected earliest in the order and
follow the instruction in that flow.
If no instructions are given, troubleshoot DTCs
according to the following priorities.
a. DTCs other than DTC P0171 / P0172 (Fuel
system too lean / too rich), DTC P0300 / P0301 /
P0302 / P0303 / P0304 (Misfire detected) and
DTC P0401 / P0402 (EGR flow malfunction)
b. DTC P0171 / P0172 (Fuel system too lean / too
rich) and DTC P0401 / P0402 (EGR flow
malfunction)
c. DTC P0300 / P0301 / P0302 / P0303 / P0304
(Misfire detected)
• Be sure to read “Precautions for Electrical Circuit
Service: in Section 00” before inspection and observe
what is written there.
• ECM replacement:
When substituting a known-good ECM, check for the
following conditions. Neglecting this check may cause
damage to a known-good ECM.
– Resistance value of all relays, actuators is as
specified respectively.
– MAP sensor, A/C refrigerant pressure sensor (if
equipped with A/C) and TP sensor are in good
condition and none of power circuits of these
sensors is shorted to ground.
• Communication of ECUs, ECM, BCM, combination
meter and TCM, is established by CAN (Controller
Area Network). (For more detail of CAN
communication for ECM, refer to “CAN
Communication System Description: ”). Therefore,
handle CAN communication line with care referring to
“Precaution for CAN Communication System: in
Section 00”.
• Immobilizer transponder code registration after
replacing ECM
When ECM is replaced with new one or with another
one, make sure to register immobilizer transponder
code to ECM correctly according to “Procedure after
ECM Replacement: in Section 10C”.
Precautions of ECM Circuit Inspection
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• ECM connectors are waterproofed. Each terminal of
the ECM connectors is sealed up with the grommet.
Therefore, when measuring circuit voltage, resistance
and/or pulse signal at ECM connector, do not insert
the tester’s probe into the sealed terminal at the
harness side. When measuring circuit voltage,
resistance and/or pulse signal at ECM connector,
connect the special tool to the ECM connectors. And,
insert the tester’s probe into the special tool’s