Suzuki Grand Vitara JB627. Manual - part 55

1A-169 Engine General Information and Diagnosis: 

DTC Troubleshooting

NOTE
Before this trouble shooting is performed, read the precautions for DTC troubleshooting referring to 
“Precautions for DTC Troubleshooting”.

 

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

A/F sensor signal check
1) Connect scan tool with ignition switch turned OFF.
2) Warm up engine to normal operating temperature and 

keep it at 2000 r/min. for 60 sec.

3) Repeat racing engine (Repeat depressing accelerator 

pedal 5 to 6 times continuously to enrich A/F mixture and 
take foot off from pedal to enlean it).

4) Check for A/F sensor (bank-1) output current displayed 

on scan tool.

Does A/F sensor output current between –0.2 mA and 0.2 
mA?

Intermittent trouble.
Check for intermittent 
referring to “Intermittent 
and Poor Connection 
Inspection in Section 
00”.

Go to Step 3.

3

A/F sensor circuit check
1) Disconnect connector from A/F sensor (bank-1) and 

ECM with ignition switch turned OFF.

2) Check for proper terminal connection to A/F sensor 

(bank-1) connector and ECM connector.

3) If connections are OK, check that A/F sensor (bank-1) 

circuit is as follows.
• Wiring harness resistance of each “Signal (+) circuit of 

A/F sensor (bank-1)”, “Signal (–) circuit of A/F sensor 
(bank-1)” is less than 1 

Ω.

• Insulation resistance between “Signal (+) circuit of A/F 

sensor (bank-1)” and vehicle body ground is infinity.

• Insulation resistance between “Signal (+) circuit of A/F 

sensor (bank-1)” and “Signal (–) circuit of A/F sensor 
(bank-1)” is infinity.

• Insulation resistance of wire harness is infinity 

between “Signal (+) circuit of A/F sensor (bank-1)” 
terminal and each other terminal at A/F sensor (bank-
1) connector.

• Insulation resistance of wire harness is infinity 

between “Signal (–) circuit of A/F sensor (bank-1)” 
terminal and each other terminal at A/F sensor (bank-
1) connector.

• Circuit voltage between “Signal (+) circuit of A/F 

sensor (bank-1)” and vehicle body ground is 0 V with 
ignition switch tuned ON.

Are they in good condition?

Go to Step 4.

Repair or replace 
defective wiring 
harness.

4

A/F sensor heater check
1) Check A/F sensor (bank-1) referring to “Air Fuel Ratio 

(A/F) Sensor On-Vehicle Inspection in Section 1C”.

Is A/F sensor in good condition?

Substitute a known 
good ECM and recheck. 
If ECM OK, replace A/F 
sensor (bank-1).

Replace A/F sensor 
(bank-1).

Engine General Information and Diagnosis:  1A-170

DTC P2240: O2 Sensor Positive Current Control Circuit / Open (Sensor-1, Bank-2) 

S6JB0B1104072

System and Wiring Diagram

A/F Sensor Description
Refer to “A/F Sensor Description”

DTC Detecting Condition and Trouble Area

4

3

9

PNK

6

2

1

8

5

BLK/WHT

BLK

PNK

GRN

C37-35

C37-78

C37-38

C37-37

BLK

BLK

BLU

WHT

C37-36

C37-79

BRN

YEL

BLU/YEL

BLU/RED

PNK/BLU

BLK/YEL

10

7

11

5 V

5 V

1

3 2

4

5

6

7

8

9

1110

12

13

14

15

16

17

18

19

20

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

33

34

35

36

37

38

39

40

32

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

63

64

65

66

67

68

69

70

71

72

73

74

75

76

77

78

79

80

81

d

a

b

c

I6JB01110105-01

a. Signal (+) circuit of A/F sensor (bank-2)

1. HO2S heater relay

5. IG COIL fuse

9. ECM

b. Signal (–) circuit of A/F sensor (bank-2)

2. Shield wire

6. A/F sensor

10. Adjusting resistor (if equipped)

c. Control circuit of A/F sensor (bank-2) heater

3. Ignition Switch

7. A/F sensor heater

11. A/F sensor element

d. Control ground circuit of A/F sensor (bank-2) heater

4. O2 HTR fuse

8. To A/F sensor (bank-1), HO2S 

(bank-1 and -2) (if equipped)

DTC detecting condition

Trouble area

Impedance of A/F sensor element is higher than 250 

Ω for more than 5 sec. 

even though A/F sensor heater is turned ON with engine running.
(1 driving cycle detection logic)

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

1A-171 Engine General Information and Diagnosis: 

DTC Confirmation Procedure

NOTE
Check to make sure that following conditions are satisfied when using this “DTC Confirmation 
Procedure”.
• The following DTC is not detected: A/F sensor heater

 

1) With ignition switch turned OFF, connect scan tool to DLC.
2) Turn ON ignition switch and clear DTC.
3) Start engine and warm up to normal operating temperature.
4) Run engine at idle speed for 1 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”.

 

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

A/F sensor signal check
1) Connect scan tool with ignition switch turned OFF.
2) Warm up engine to normal operating temperature and 

keep it at 2000 r/min. for 60 sec.

3) Repeat racing engine (Repeat depressing accelerator 

pedal 5 to 6 times continuously to enrich A/F mixture and 
take foot off from pedal to enlean it).

4) Check for A/F sensor (bank-2) output current displayed 

on scan tool.

Does A/F sensor output current between –0.2 mA and 0.2 
mA?

Intermittent trouble.
Check for intermittent 
referring to “Intermittent 
and Poor Connection 
Inspection in Section 
00”.

Go to Step 3.

3

A/F sensor circuit check
1) Disconnect connector from A/F sensor (bank-2) with 

ignition switch turned OFF.

2) Check for proper terminal connection to A/F sensor 

(bank-2) connector and ECM connector.

3) If connections are OK, check that A/F sensor (bank-2) 

circuit is as follows.
• Wiring harness resistance of each “Signal (+) circuit of 

A/F sensor (bank-2)”, “Signal (–) circuit of A/F sensor 
(bank-2)”, “Control circuit of A/F sensor (bank-2) 
heater” and “Control ground circuit of A/F sensor 
(bank-2) heater” is less than 1 

Ω.

Are they in good condition?

Go to Step 4.

Repair or replace 
defective wiring 
harness.

4

A/F sensor heater check
1) Check heater resistance of A/F sensor (bank-2) referring 

to “Air Fuel Ratio (A/F) Sensor On-Vehicle Inspection in 
Section 1C”.

Is A/F sensor heater in good condition?

Substitute a known 
good ECM and recheck. 
If ECM OK, replace A/F 
sensor (bank-2).

Replace A/F sensor 
(bank-2).

Engine General Information and Diagnosis:  1A-172

DTC P2241 / P2242: O2 Sensor Positive Current Control Circuit Low / High (Sensor-1, Bank-2)

S6JB0B1104073

Wiring Diagram
Refer to “DTC P2240: O2 Sensor Positive Current Control Circuit / Open (Sensor-1, Bank-2)”

A/F Sensor Description
Refer to “A/F Sensor Description”

DTC Detecting Condition and Trouble Area

DTC Confirmation Procedure

NOTE
Check to make sure that following conditions are satisfied when using this “DTC Confirmation 
Procedure”.
• The following DTC is not detected: A/F sensor heater

 

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

DTC detecting condition

Trouble area

DTC P2241 O2 Sensor Positive Current Control Circuit Low 
(Sensor-1, Bank-2):
Circuit voltage of A/F sensor (+) terminal is lower than 0.4 V or 
A/F sensor circuit is short between (+) terminal wire and (–) 
terminal wire with engine running.
(1 driving cycle detection logic)
DTC P2242 O2 Sensor Positive Current Control Circuit High 
(Sensor-1, Bank-2):
Circuit voltage of A/F sensor (+) terminal is higher than 3.5 V 
with engine running
(1 driving cycle detection logic)

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