Suzuki Grand Vitara JB627. Manual — part 31

1A-73 Engine General Information and Diagnosis:

DTC Detecting Condition and Trouble Area

DTC Confirmation Procedure

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”.

DTC detecting condition

Trouble area

DTC P0057 HO2S Heater Control Circuit Low (Sensor-2, Bank-2):
Circuit current of HO2S (bank-2) heater is lower than specification
(0.16 – 0.28 A depending on battery voltage) for more than 1 sec.
continuously while control duty of HO2S sensor heater is ON with
engine running.
(2 driving cycle detection logic)
DTC P0058 HO2S Heater Control Circuit High (Sensor-2, Bank-2):
Circuit current of HO2S sensor (bank-2) heater is higher than 5 A at
ON duty pulse or 0.2 A at OFF duty pulse for more than 1 sec.
continuously while control duty of HO2S sensor heater is ON with
engine running.
(2 driving cycle detection logic)

• HO2S heater circuit
• HO2S
• ECM

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 DTC check

Are there DTC P0031 and/or P0051?

Go to applicable DTC
flow referring to “DTC
P0031 / P0032: HO2S
Heater Control Circuit
Low / High (Sensor-1,
Bank-1)” and/or “DTC
P0051 / P0052: HO2S
Heater Control Circuit
Low / High (Sensor-1,
Bank-2)”.

Go to Step 3.

3

HO2S heater relay and its circuit check
1) Disconnect connector from HO2S (bank-2) with ignition

switch turned OFF.

2) Check for proper terminal connection to HO2S (bank-2)

connector.

3) If connections are OK, check that HO2S (bank-2) heater

control circuit is as follows.
• Circuit voltage between “Power supply circuit of HO2S

(bank-2) heater” and vehicle body ground is battery
voltage with ignition switch turned ON.

Is it in good condition?

Go to Step 4.

Repair or replace
defective wiring
harness.

Engine General Information and Diagnosis: 1A-74

4

HO2S heater circuit check
1) Check that HO2S (bank-2) heater control circuit is as

follows.
• Circuit voltage between “Control circuit of HO2S

(bank-2) heater” and vehicle body ground is 0 V with
ignition switch turned ON.

Is it good condition?

Go to Step 5.

Repair or replace
defective wiring
harness.

5

HO2S heater circuit check
1) Disconnect connectors form ECM and check for proper

terminal connection to ECM connector.

2) If connections are OK, check that HO2S (bank-2) heater

circuit is as follows.
• Insulation resistance of wire harness is infinity

between “Control circuit of HO2S (bank-2) heater”
terminal and each other terminal at HO2S (bank-2)
connector.

• Wiring harness resistance of “Control circuit of HO2S

(bank-2) heater” is less than 1

Ω.

• Insulation resistance between “Control circuit HO2S

(bank-2) heater” and vehicle body ground is infinity.

Is it in good condition?

Go to Step 6.

Repair or replace
defective wiring
harness.

6

HO2S heater check
1) Check heater resistance of HO2S (bank-2) referring to

“Heated Oxygen Sensor (HO2S-2) Heater On-Vehicle
Inspection (If Equipped) in Section 1C”.

Is HO2S (bank-2) heater in good condition?

Substitute a known
good ECM and recheck.

Replace HO2S (bank-
2).

Step

Action

Yes

No

1A-75 Engine General Information and Diagnosis:

DTC P0101: Mass Air Flow Circuit Range / Performance

S6JB0B1104018

Wiring Diagram

DTC Detecting Condition and Trouble Area

DTC Confirmation Procedure

WARNING

!

• When performing a road test, select a place where there is no traffic or possibility of a traffic

accident and very careful during testing to avoid occurrence of an accident.

• Road test should be carried out with 2 persons, a driver and a tester, on a level road.

NOTE
Check to make sure that the following conditions are satisfied when using this “DTC Confirmation
Procedure”.
• Intake air temperature: higher than –10

°C (14 °F).

• Atmospheric pressure: higher than 75 kPa (560 mmHg) (Altitude: lower than 2790 m (9150 ft)).
• The following DTCs are not detected: MAP sensor, IAT sensor, ECT sensor, EGR system, barometric

pressure sensor and MAF sensor (other than P0101).

BLU/BLK

BLU/BLK

BLU/BLK

BLK/RED

BLK/RED

BLK/RED

BLU

12V 5V

E23-8

E23-16
E23-2
E23-3

WHT/GRN

C37-59

C37-58

C37-39

C37-73

C37-80

BLK/YEL

BLK/ORN

BLK/ORN

BLK/YEL
BLK/YEL

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

E23

C37

BLK/ORN

C37-81

BLK/YEL

BLK/WHT

5V

GRY/GRN

GRY/GRN

BLU/BLK

BLU

RED

C37-23

C37-24

C37-67

C37-4

LT GRN

2

4

3

1

5

P

S

G

I6JB01110027-03

P: MAF sensor power supply circuit

1. MAF and IAT sensor

4. ECM

S: MAF sensor signal circuit

2. Ignition switch

5. To other sensors

G: MAF sensor ground circuit

3. Main relay

DTC detecting condition

Trouble area

Ratio of MAF sensor signal to estimated MAF based on engine speed
and MAP signal is more than 1.3 or less than 0.8 for more than 10 sec.
(2 driving cycle detection logic, monitoring once per driving cycle)

• Air intake system (Clog or leakage)
• MAF sensor and its circuit
• MAP sensor and its circuit
• Exhaust system (clogged WU-TWC

converter)

• ECM

Engine General Information and Diagnosis: 1A-76

1) With ignition switch OFF, connect scan tool.
2) Turn ON ignition switch and clear DTC by using scan tool if any.
3) Start engine and warm up to normal operating temperature.
4) Increase vehicle speed till engine speed is reached 1200 – 4800 r/min.
5) Drive vehicle for 1 min. at engine speed 1200 – 4800 r/min.
6) Stop vehicle and check DTC and pending DTC by using scan tool.

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

Visual inspection
1) Check MAF sensor and air intake system for:

• Objects which block measuring duct and resistor of

MAF sensor.

• Other air flow which does not pass the MAF sensor.

Are they in good condition?

Go to Step 3.

Repair or replace.

3

MAF sensor performance check
1) With ignition switch OFF, connect scan tool to DLC.
2) Start engine and warm up to normal operation

temperature.

3) Check MAF value using scan tool. (Refer to “Scan Tool

Data” for normal value.)

Is normal valve indicated?

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

Go to Step 4.

4

Wire harness check
1) Check power supply, signal and ground circuits of MAF

sensor for condition referring to Step 3 and 4 of “DTC
P0102 / P0103: Mass Air Flow Circuit Low / High Input”.

Are they in good condition?

Go to Step 5.

Repair or replace.

5

MAF sensor signal check
1) Turn ignition switch OFF position.
2) Connect connectors to MAF sensor and ECM.
3) Check MAF sensor signal voltage referring to “Mass Air

Flow (MAF) and Intake Air Temperature (IAT) Sensor
On-Vehicle Inspection in Section 1C”.

Is each value within specified range?

Go to Step 6.

Replace MAF and IAT
sensor.

6

MAP sensor check
1) Check MAP sensor for performance referring to

“Manifold Absolute Pressure (MAP) Sensor Removal
and Installation (If Equipped) in Section 1C”.

Is it in good condition?

Substitute a known
good ECM and recheck.
If ECM is OK, replace
exhaust manifold (built-
in WU-TWC converter)

Replace MAP sensor.