Suzuki GA413, Service Manual

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PRECAUTION IN DIAGNOSING TROUBLE
Don’t disconnect couplers from ECM, battery cable at battery,
ECM ground wire harness from engine or main fuse before con-
firming diagnostic information (DTC, freeze frame data, etc.)
stored in ECM memory. Such disconnection will erase memo-
rized information in ECM memory.
Diagnostic information stored in ECM memory can be cleared
as well as checked by using SUZUKI scan tool (Tech-1) or ge-
neric 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.
Priorities for diagnosing troubles (Vehicle with EGR valve).
If multiple diagnostic trouble codes (DTCs) are stored, proceed
to the flow table of the DTC which has detected earliest in the
order and follow the instruction in that table.
If no instructions are given, troubleshoot diagnostic trouble
codes according to the following priorities.
1. Diagnostic trouble codes (DTCs) other than DTC
P0171 / P0172 (Fuel system too lean / too rich), DTC
P0300 / P0301 / P0302 / P0303 / P0304 (Misfire detected) and
DTC P0400 (EGR flow malfunction)
2. DTC P0171 / P0172 (Fuel system too lean / too rich) and DTC
P0400 (EGR flow malfunction)
3. DTC P0300 / P0301 / P0302 / P0303 / P0304 (Misfire de-
tected)
Be sure to read “Precautions for Electrical Circuit Service” in
Section 0A before inspection and observe what is written there.
ECM Replacement
When substituting a known-good ECM, check for following
conditions. Neglecting this check may cause damage to a
known-good ECM.
– Resistance value of all relays, actuators is as specified re-
spectively.
– MAP sensor and TP sensor are in good condition and none of
power circuits of these sensors is shorted to ground.
When taking measurements at electrical connectors using a tes-
ter probe, be sure to insert the probe from the wire harness side
(backside) of the connector.
1. Connector
2. Probe
6-10 ENGINE GENERAL INFORMATION AND DIAGNOSIS
GA413
supple