MARUTI SUZUKI Wagon R, Manual

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Engine General Information and Diagnosis: Bi-Fuel LPG model 1A-2
• Communication of LPG control module, ECM and
combination meter is established by CAN (Controller
Area Network). (For more details of CAN
communication for LPG control module, refer to “CAN
Communication System Description”: in Section
10H).
Therefore, handle CAN communication line with care
referring to “Precaution for CAN Communication
System”: in Section 00.
Precaution for ECM and LPG Control Module
Circuits Inspection
AENAR90A1100005
Do not measure voltage and/or pulse signal of ECM and
LPG control module inserting tester probe in sealed
terminal of ECM and LPG control module.
When measuring circuit voltage and/or pulse signal of
ECM and LPG control module, be sure to connect
service wires (5) to each sensor (1) and sensor
connector (2). Otherwise, sealed terminal, ECM and
LPG control module and its circuits may be damaged.
General Description
Description of Cleanliness and Care
AENAR90A1101001
• An automobile engine is a combination of many
machined, honed, polished and lapped surfaces with
tolerances that are measured in the thousandth of a
millimeter (ten thousandth of an inch).
Accordingly, when any internal engine parts are
serviced, care and cleanliness are important.
It should be understood that proper cleaning and
protection of machined surfaces and friction areas is
part of the repair procedure. This is considered
standard shop practice even if not specifically stated.
• A liberal coating of engine oil should be applied to
friction areas during assembly in order to protect and
lubricate surfaces on initial operation.
• Whenever valve train components, pistons, piston
rings, connecting rods, connecting rod bearings, or
crankshaft main bearings are removed for service,
they should be kept organized.
At the time of installation, they should be installed in
the same locations with the same combinations as
those before removal.
• Battery cable should be disconnected before
performing any major work on the engine.
Failure to disconnect cable may result in damage to
wire harness or other electrical parts.
Engine Diagnosis General Description
AENAR90A1101002
The engine and emission control systems in this vehicle
are controlled by ECM and LPG control module. ECM
and LPG control module has an OBD system which
detects a malfunction in this system and abnormality of
those parts that influence the engine exhaust emission.
When diagnosing engine troubles, be sure to have full
understanding of the outline of “OBD System
Description”: Bi-Fuel LPG model and each item in
“Precautions for Diagnosing Trouble”: Bi-Fuel LPG
model and execute diagnosis according to “Engine and
Emission Control System Check”: Bi-Fuel LPG model.
There is a close relationship between the emission
system, engine mechanical, engine cooling system,
ignition system, exhaust system, etc. in their structure
and operation. In case of an engine trouble, even when
the MIL and/or LPG warning light does not turn on,
diagnosis should be performed according to “Engine and
Emission Control System Check”: Bi-Fuel LPG model.
OBD System Description
AENAR90A1101003
ECM
General Description
ECM in this vehicle has the following functions.
• When the ignition switch is turned to ON position with
the engine stopped, MIL (1) turns on in order to check
the MIL (1) and its circuit.
• When ECM detects a malfunction which gives an
adverse effect to vehicle emission for more than
specified driving cycles, it turns on or flashes MIL in
the combination meter and stores the DTC in its
memory.
(If it detects normal condition for continuously three
driving cycles after detecting a malfunction, it turns
OFF MIL although DTC is stored in its memory
remains as a history DTC.)
3. Voltmeter 4. Oscilloscope
1
3
5
2
4
I8C50A110001-02