Suzuki Grand Vitara JB416 / JB420 / JB419. Manual - part 31

1A-71 Engine General Information and Diagnosis: For Petrol Engine Model

DTC Detecting Condition and Trouble Area

DTC Confirmation Procedure

1) With ignition switch turned OFF, connect scan tool.
2) Turn ON ignition switch and clear DTC using scan tool.
3) Start engine and warm up to normal operating temperature.
4) Run engine at idle speed for 4 min. or more.
5) Check DTC and pending DTC.

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”.

DTC detecting condition

Trouble area

Impedance of A/F sensor element is more than 44

Ω for 200

sec. even though A/F sensor heater is turned ON for more than
specified time with engine running. (A/F sensor does not
activate)
(2 driving cycle detection logic)

• A/F sensor heater circuit
• A/F sensor heater
• ECM

Step

Action

Yes

Was “Engine and Emission Control System Check”
performed?

Go to Step 2.

Go to “Engine and
Emission Control
System Check: For
Petrol Engine Model”.

DTC check

Is there any DTC(s) other than P0030?

Go to applicable DTC
diag. flow.

Go to Step 3.

Sensor circuit check
1) Disconnect connectors from A/F sensor and ECM with

ignition switch turned OFF.

2) Check for proper connection to A/F sensor terminals and

ECM terminals.

3) If wire and connection are OK, measure each wire

resistance of A/F sensor circuit (sensor and heater)
between A/F sensor connector and ECM connector.

Is each measured wire resistance lower than 1

Ω

Go to Step 4.

Repair or replace
defective wire circuit.

Sensor circuit insulation check
1) Measure resistance between wire and wire at sensor

circuit terminals of A/F sensor connector (no continuity
check).

Is measured resistance infinity?

Substitute a known
good A/F sensor and
recheck.

Repair or replace
defective circuit.

Engine General Information and Diagnosis: For Petrol Engine Model 1A-72

DTC P0031 / P0032: HO2S Heater Control Circuit Low / High (Sensor-1)

S6JB0A1114016

Wiring Diagram
Refer to “DTC P0030: HO2S Heater Control Circuit (Sensor-1): For Petrol Engine Model”.

A/F Sensor Description
Refer to “A/F Sensor Description: For Petrol Engine Model”.

DTC Detecting Condition and Trouble Area

DTC Confirmation Procedure

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”.

DTC detecting condition

Trouble area

P0031:
Heater control circuit voltage of A/F sensor is lower than
specification for more than specified time continuously even
though control duty ratio of A/F sensor heater is less than 90%
with engine running. (Heater control duty pulse is not detected
in its circuit of ECM)
(2 driving cycle detection logic)
P0032:
Heater control circuit voltage of A/F sensor is higher than
specification for more than specified time continuously even
though control duty ratio of A/F sensor heater is more than 10%
with engine running. (Heater control duty pulse is not detected
in its circuit of ECM)
(2 driving cycle detection logic)

• A/F sensor heater circuit
• A/F sensor heater
• ECM

Step

Action

Yes

Was “Engine and Emission Control System Check”
performed?

Go to Step 2.

Go to “Engine and
Emission Control
System Check: For
Petrol Engine Model”.

A/F sensor heater circuit check
1) Disconnect connector from A/F sensor with ignition

switch turned OFF.

2) Check for proper connection to A/F sensor connector.
3) If connection are OK, measure voltage between heater

power terminal of A/F sensor connector and vehicle
body ground with ignition switch turned ON.

Is measured voltage 10 – 14 V?

Go to Step 9.

Go to Step 3.

1A-73 Engine General Information and Diagnosis: For Petrol Engine Model

HO2S heater fuse check
1) Check for “O2 HTR” fuse (1) blown.

For J20 engine

For M16 engine

Is “O2 HTR” fuse in good condition?

Go to Step 5.

Go to Step 4.

A/F sensor and HO2S heater resistance check
1) Disconnect connector from HO2S-2 with ignition switch

turned OFF.

2) Check heater resistance of A/F sensor and HO2S

referring to “Air Fuel Ratio (A/F) Sensor On-Vehicle
Inspection: For Petrol Engine Model in Section 1C” and
“Heated Oxygen Sensor (HO2S-2) Heater On-Vehicle
Inspection: For Petrol Engine Model in Section 1C”.

Are A/F sensor heater and HO2S heater in good condition?

Go to Step 6.

Replace defective
sensor.

Step

Action

Yes

I5JB0A110028-02

I5JB0A110029-02

Engine General Information and Diagnosis: For Petrol Engine Model 1A-74

HO2S heater relay power circuit check
1) Remove integration relay No.2 (for J20 engine) (1) or

HO2S heater relay (for M16 engine) (2) with ignition
switch turned OFF.

2) Check for proper connection to relay connector.
3) If connection are OK, measure voltage between each

relay power terminal of relay connector and vehicle body
ground with ignition switch tuned ON.

For J20 engine

For M16 engine

Is each measured voltage 10 – 14 V?

Go to Step 6.

Power circuit is open.

Check HO2S heater relay
1) Check integration relay No.2 (for J20 engine) or HO2S

heater relay (for M16 engine) referring to “Control Relay
Inspection: For Petrol Engine Model in Section 1C”.

Is it in good condition?

Go to Step 7.

Replace relay.

A/F sensor heater circuit check
1) Measure insulation resistance between heater terminals

of A/F sensor connector.

Is measured resistance infinity?

Go to Step 8.

Repair or replace short
wire.

HO2S heater relay circuit check
1) Measure wire resistance between coil ground terminal of

relay connector and vehicle body ground.

Is measured resistance lower than 1

Ω

Output wire of relay
connector is open or
short to ground.

Repair or replace
defective circuit.

A/F sensor heater check
1) Check heater resistance of A/F sensor referring to “Air

Fuel Ratio (A/F) Sensor On-Vehicle Inspection: For
Petrol Engine Model in Section 1C”.

Is A/F sensor heater in good condition?

Go to Step 10.

Replace A/F sensor.

Step

Action

Yes

I5JB0A110030-02

I5JB0A110031-03

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