Suzuki Grand Vitara 2011 Manual page 186

1A-117 Engine General Information and Diagnosis: For Petrol Engine Model
DTC Troubleshooting
NOTE
Before this trouble shooting is performed, read the precautions for DTC troubleshooting referring to
"Precautions for DTC Troubleshooting: For Petrol Engine Model".
Step
1 Was "Engine and Emission Control System Check"
performed?
2 HO2S-2 ground check
1) Disconnect connector from HO2S-2 with ignition switch
turned OFF.
2) Check for proper connection to HO2S-2 connector at
"PNK", "BLK/RED", "GRN" and "RED" wire terminals.
3) If connections are OK, measure resistance between
"GRN" wire terminal of HO2S-2 connector and engine
ground.
Is resistance less than 3
3 Wire circuit check
1) Disconnect connectors from ECM with ignition switch
turned OFF.
2) Measure resistance between "RED" wire terminal of
HO2S-2 connector and "C37-11" terminal of ECM
connector.
Is resistance less than 3
4 HO2S-2 signal circuit check
1) Turn ON ignition switch.
2) Measure voltage between "RED" wire terminal of HO2S-
2 connector and vehicle body ground.
Is voltage 0 V?
5 HO2S-2 heater circuit check
1) Check HO2S-2 heater circuit referring to "DTC P0037 /
P0038: HO2S Heater Control Circuit Low / High
(Sensor-2): For Petrol Engine Model".
Is circuit in good condition?
6 HO2S-2 check
1) Check HO2S-2 referring to "Heated Oxygen Sensor
(HO2S-2) Heater On-Vehicle Inspection: For Petrol
Engine Model in Section 1C".
Is it in good condition?
Action
Ω
?
Ω
?
Yes
Go to Step 2.
Go to Step 3.
Go to Step 4.
Go to Step 5.
Go to Step 6.
Substitute a known-
good ECM and recheck.
No
Go to "Engine and
Emission Control
System Check: For
Petrol Engine Model".
"GRN" and/or "GRY/
GRN" wire is open or
high resistance circuit.
Poor "C37-57" terminal
connection. Faulty ECM
ground.
If they are OK,
substitute a known-
good ECM and recheck.
"RED" wire is high
resistance circuit or
open circuit. Poor "C37-
11" terminal connection.
If they are OK,
substitute a known-
good ECM and recheck.
"RED" wire is shorted to
other circuit.
Repair HO2S-2 circuit. If
circuit is OK, substitute
a known-good ECM and
recheck.
Replace HO2S-2.