Suzuki Liana RH413, Service Manual

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1A-63 Engine General Information and Diagnosis:
11) Stop vehicle (do not turn ignition switch OFF). Confirm test results according to “Test Result Confirmation Flow” in
“DTC Confirmation Procedure” of “DTC P0420: Catalyst System Efficiency below Threshold”.
DTC Troubleshooting
IYSY01111045-01
A: *Usual driving – Driving at 50 - 60 km/h, 30 - 40 mph including short stop according to traffic signal. (under driving condition other than high-load, high-
engine speed, rapid accelerating and decelerating)
Step Action Yes No
1 Was “Engine and Emission Control System Check”
performed? Go to Step 2. Go to “Engine and
Emission Control
System Check”.
2 Check exhaust system for leakage, loose connection
and damage
Is it in good condition?
Go to Step 3. Repair or replace.
3 Check HO2S-2 and its circuit
Was HO2S-2 output voltage indicated on scan tool in Step 3)
of “DTC Confirmation Procedure” less than 1.275 V?
Go to Step 4. “WHT” or “ORN” circuit
short to power supply
circuit or HO2S-2
malfunction.
4 Check short term fuel trim
Did short term fuel trim vary within –20 – +20% range in Step
3) of “DTC Confirmation Procedure”?
Check “WHT” or “ORN”
wire for open and short,
and connection for poor
connection.
If wire and connection
are OK, replace HO2S-
2. Check fuel system.
Go to “DTC P0171 /
P0172: Fuel System
Too Lean / Rich”.