Suzuki Wagon R Plus RB310, Service Manual

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ENGINE GENERAL INFORMATION AND DIAGNOSIS (M13 ENGINE) 6-2-111
DTC Confirmation Procedure
1) Connect scan tool to DLC with ignition switch turned OFF.
2) Turn ON ignition switch and clear DTC, pending DTC and freeze frame data by using scan tool.
3) Start engine and run it for 10 sec.
4) Check DTC by using scan tool.
Troubleshooting
Step Action Yes No
1 Was “Engine and Emission Control System
Check” performed? Go to Step 2. Go to “Engine and Emis-
sion Control System
Check” in this section.
2 Check sensor circuit.
1) Disconnect connectors from ECM with igni-
tion switch turned OFF.
2) Remove ECM from vehicle body and con-
nect connectors to ECM.
3) Measure voltage between “E22-9” wire ter-
minal of ECM connector and vehicle body
ground with engine running.
Is voltage within 1.23 – 3.91 V?
Intermittent trouble.
Check for intermittent
refer to “Intermittent and
Poor Connection Inspec-
tion” in Section 0A.
If OK, substitute a known-
good ECM and recheck. Go to Step 3.
3 Check sensor circuit for open.
1) Disconnect connector from knock sensor
with ignition switch turned OFF.
2) Turn ON ignition switch, measure voltage
between “WHT” wire of knock sensor con-
nector and engine ground. See Fig. 1.
Is voltage 4 – 6 V?
Go to Step 6. Go to Step 4.
4 Check sensor circuit for open.
1) Turn ON ignition switch, measure voltage
between “E22-9” wire terminal of ECM con-
nector and engine ground.
Is voltage 4 – 6 V?
“WHT” wire in open cir-
cuit. Go to Step 5.
5 Check sensor circuit for short.
1) Disconnect connectors from ECM with igni-
tion switch turned OFF.
2) Measure resistance between “E22-9” termi-
nal of ECM connector and vehicle body
ground.
Is resistance infinity?
Go to Step 6. “WHT” wire in shorted to
ground circuit.
If wire is OK, substitute a
known-good ECM and
recheck.
6 Check sensor circuit for short.
1) Turn ON ignition switch, measure voltage
between “E22-9” terminal of ECM connector
and vehicle body ground.
Is voltage 0 V?
Go to Step 7. “WHT” wire in shorted to
other circuit.
7 Check sensor circuit for high resistance.
1) Measure resistance between “E22-9” wire
terminal of ECM connector and “WHT” wire
terminal of knock sensor harness connec-
tor.
Is resistance below
5Ω
?
Faulty knock sensor “WHT” wire in high resis-
tance circuit.