Suzuki Grand Vitara JB627. Manual - part 27

1A-57 Engine General Information and Diagnosis: 

Excessive hydrocarbon 
(HC) emission or carbon 
monoxide (CO)

Engine not at normal operating 
temperature
Clogged air cleaner

Refer to “Air Cleaner Filter Inspection and 
Cleaning in Section 1D”.

Vacuum leaks

Refer to “Engine Vacuum Check in Section 
1D”.

Faulty spark plug

Refer to “Spark Plug Inspection in Section 1H”.

Faulty ignition coil with ignitor

Refer to “Ignition Coil Assembly (Igniter and 
Ignition Coil) Inspection in Section 1H”.

Low compression

Refer to “Compression Check in Section 1D”.

Lead contamination of three way 
catalytic converter

Check for absence of filler neck restrictor.

Faulty evaporative emission control 
system

Refer to “EVAP Canister Purge Valve and Its 
Circuit Inspection in Section 1B”.

Fuel pressure out of specification
– Dirty fuel filter
– Dirty or clogged fuel hose or pipe
– Faulty fuel pressure regulator
– Faulty fuel pump

Refer to “Fuel Pressure Check”.

Closed loop system (A/F feedback 
compensation) fails (faulty TP sensor, 
poor performance of ECT sensor or 
MAF sensor)

Refer to “Electric Throttle Body Assembly On-
Vehicle Inspection in Section 1C”, “Engine 
Coolant Temperature (ECT) Sensor Inspection 
in Section 1C” or “Mass Air Flow (MAF) and 
Intake Air Temperature (IAT) Sensor On-
Vehicle Inspection in Section 1C”.

Faulty electric throttle body assembly

Refer to “Electric Throttle Body Assembly On-
Vehicle Inspection in Section 1C”.

Faulty accelerator pedal position (APP) 
sensor assembly

Refer to “Accelerator Pedal Position (APP) 
Sensor Assembly Inspection in Section 1C”.

Faulty injector

Refer to “Fuel Injector Circuit Check”.

Faulty ECM

Refer to “Inspection of ECM and Its Circuits”.

Excessive nitrogen 
oxides (NOx) emission

Improper ignition timing

Refer to “Ignition Timing Inspection in Section 
1H”.

Lead contamination of catalytic 
converter

Check for absence of filler neck restrictor.

Faulty EGR system (if equipped)

Refer to “EGR System Inspection (If Equipped) 
in Section 1B”.

Fuel pressure out of specification
– Dirty fuel filter
– Dirty or clogged fuel hose or pipe
– Faulty fuel pressure regulator
– Faulty fuel pump

Refer to “Fuel Pressure Check”.

Closed loop system (A/F feedback 
compensation) fails (faulty TP sensor, 
poor performance of ECT sensor or 
MAF sensor)

Refer to “Electric Throttle Body Assembly On-
Vehicle Inspection in Section 1C”, “Engine 
Coolant Temperature (ECT) Sensor Inspection 
in Section 1C” or “Mass Air Flow (MAF) and 
Intake Air Temperature (IAT) Sensor On-
Vehicle Inspection in Section 1C”.

Faulty electric throttle body assembly

Refer to “Electric Throttle Body Assembly On-
Vehicle Inspection in Section 1C”.

Faulty accelerator pedal position (APP) 
sensor assembly

Refer to “Accelerator Pedal Position (APP) 
Sensor Assembly Inspection in Section 1C”.

Faulty injector

Refer to “Fuel Injector Circuit Check”.

Faulty ECM

Refer to “Inspection of ECM and Its Circuits”.

Condition

Possible cause

Correction / Reference Item

Engine General Information and Diagnosis:  1A-58

Malfunction Indicator Lamp Does Not Come ON with Ignition Switch ON and Engine Stop (but 
Engine Can Be Started)

S6JB0B1104012

Wiring Diagram

Circuit Description
When the ignition switch is turned ON, ECM causes the main relay to turn ON (close the contact point). Then, ECM 
being supplied with the main power, transmits indication ON signal of malfunction indicator lamp (MIL) to combination 
meter in order to turn MIL ON. And then, combination meter turns MIL ON. When the engine starts to run and no 
malfunction is detected in the system, ECM transmits MIL indication OFF signal to combination meter in order to turn 
MIL OFF. And then, combination meter turns MIL OFF, but if a malfunction was or is detected, MIL remains ON even 
when the engine is running.

BLK/WHT

BLU/BLK

BLU/BLK

BLU/BLK

WHT/GRN

BLK/RED

BLK/RED

BLK/RED

BLK/YEL

BLU

12V

5V

2

3

8

6

5

7

WHT/RED

WHT/BLU

WHT/RED

WHT/BLU

E23-8  

E23-9  

E23-2  

E23-16  

E23-17  

E23-3  

10

12

11

1

PPL/RED

C37-73  

C37-39  
C37-58  

BLK/ORN

C37-59  

C37-80  BLK/ORN
C37-81  BLK/ORN

BLK/YEL
BLK/YEL
BLK/YEL

4

WHT

RED

WHT

RED

BLK

9

13

12

12

12

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

1

2

3

4

5

6

7

8

9

10

11

17

1615141312

2221201918

G28

[B]

G28-15

G

G28-13

P

[A]

C37

E23

I6JB01110026-02

[A]: ECM connector (viewed from harness side)

3. Main relay

9. ABS or ESP

® control module

[B]: Combination meter connector (viewed from harness side)

4. Malfunction indicator lamp in combination meter 10. “FI” fuse

P: Combination meter power supply circuit

5. “IG COIL” fuse

11. “IGN” fuse

G: Combination meter ground circuit

6. “METER” fuse

12. CAN communication line

1. Fuse box No.2

7. ECM

13. To other control module TCM (A/T 

model), BCM, 4WD control module (if 
equipped), keyless start control module 
(if equipped) and steering angle sensor 
(ESP

® model)

2. Ignition switch

8. Junction block

1A-59 Engine General Information and Diagnosis: 

Troubleshooting

NOTE

• Before performed troubleshooting, be sure to read the “Precautions of ECM Circuit Inspection”.
• When measuring circuit voltage, resistance and/or pulse signal at ECM connector, connect the 

special tool to ECM and/or the ECM connectors referring to “Inspection of ECM and Its Circuits”.

 

Step

Action

Yes

No

1

MIL power supply check
1) Turn ignition switch to ON position.

Do other warning lights come ON?

Go to Step 2.

Go to Step 4.

2

DTC check
1) Connect scan tool to DLC with ignition switch turned 

OFF.

2) Turn ON ignition switch and check DTC.

Is there DTC(s) U0073 and/or U0121?

Go to applicable DTC 
diag. flow.

Go to Step 3.

3

DTC check in ABS or ESP

® control module

1) Check DTC in ABS or ESP

® control module.

Is there DTC(s) U1073 and/or U1100?

Go to applicable DTC 
diag. flow.

Substitute a known 
good combination meter 
and recheck. If MIL still 
remains OFF, substitute 
a known good ECM and 
recheck.

4

Combination meter power supply and ground circuit 
check
1) Turn ignition switch OFF position.
2) Disconnect connector from combination meter.
3) Check for proper connection to power supply and 

ground terminals of combination meter connector.

4) If connections are OK, check that combination meter 

circuit is as follows.
• Circuit voltage between combination meter power 

supply terminal and vehicle body ground is 10 – 14 V.

• Wiring harness resistance of combination meter 

ground terminal and vehicle body ground is less than 
3 

Ω.

Are they in good condition?

Go to Step 5.

Repair or replace.

5

CAN communication line circuit check
1) Check CAN communication circuit between control 

modules for open, short, high resistance and 
connections referring to Step 3 of “DTC U0073: Control 
Module Communication Bus Off”

Is circuit in good condition?

Substitute a known 
good combination meter 
and recheck. If MIL still 
remains OFF, substitute 
a known good ECM and 
recheck.

Repair or replace.

Engine General Information and Diagnosis:  1A-60

Malfunction Indicator Lamp Remains ON after Engine Starts

S6JB0B1104013

Wiring Diagram and Circuit Description
Refer to “Malfunction Indicator Lamp Does Not Come ON with Ignition Switch ON and Engine Stop (but Engine Can 
Be Started)”.

Troubleshooting

NOTE

• Before performed troubleshooting, be sure to read the “Precautions of ECM Circuit Inspection”.
• When measuring circuit voltage, resistance and/or pulse signal at ECM connector, connect the 

special tool to ECM and/or the ECM connectors referring to “Inspection of ECM and Its Circuits”.

 

Step

Action

Yes

No

1

DTC check
1) Start engine and recheck DTC of ECM and TCM (A/T 

model) while engine running.

Is there any DTC(s)?

Go to Step 2 of “Engine 
and Emission Control 
System Check”, Step 2 
of “A/T System Check in 
Section 5A”.

Go to Step 2.

2

CAN communication line circuit check
1) Check CAN communication line circuit between control 

modules for open, short, high resistance and 
connections referring to Step 9 to 14 “DTC U0073: 
Control Module Communication Bus Off”.

Is circuit in good condition?

Substitute a known 
good combination meter 
and recheck. If MIL still 
remains ON, substitute 
a known good ECM and 
recheck.

Repair or replace CAN 
communication circuit.