Suzuki Grand Vitara JB416 / JB420. Manual - part 32

1A-77 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

MAF sensor and its circuit check
1) Connect scan tool to DLC with ignition switch turned 

OFF.

2) Start engine and check MAF value displayed on scan 

tool. (Refer to “Scan Tool Data” for normal value.)

Is normal value indicated?

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

Go to Step 3.

3

MAF sensor power supply voltage check
1) Disconnect connector from MAF and IAT sensor with 

ignition switch turned OFF.

2) Turn ON ignition switch, measure voltage between 

engine ground and “BLU/BLK” wire terminal of MAF and 
IAT sensor connector.

Is voltage 10 – 14 V?

Go to Step 4.

“BLU/BLK” wire is open 
circuit.

4

MAF sensor ground circuit check
1) Turn OFF ignition switch, measure resistance between 

“BLU” wire terminal of MAF and IAT sensor connector 
and engine ground.

Is resistance below 3 

Ω

?

Go to Step 6.

Go to Step 5.

5

Ground circuit check
1) Remove ECM from its bracket with ECM connectors 

connected.

2) Measure resistance between “C37-27” terminal of ECM 

connector and engine ground.

Is resistance below 3 

Ω

?

“BLU” wire is open or 
high resistance circuit.

ECM grounds “C37-58”, 
“C37-48”, “C37-30”, 
“C37-29” and/or “C37-
15” circuit is open or 
high resistance.
If wires are OK, 
substitute a known-
good ECM and recheck.

6

MAF sensor signal circuit check
1) Disconnect connectors from ECM with ignition switch 

turned OFF.

2) Measure voltage between “RED” wire terminal of MAF 

and IAT sensor connector and engine ground with 
ignition switch turned ON.

Is voltage 0 V?

Go to Step 7.

“RED” wire is shorted to 
other circuit.

7

MAF sensor signal circuit check
1) Measure resistance between “RED” wire terminal of 

MAF and IAT sensor connector and engine ground with 
ignition switch turned OFF.

Is resistance infinity?

Go to Step 8.

“RED” wire is shorted to 
ground circuit.

8

MAF sensor signal circuit check
1) Measure resistance between “RED” wire terminal of 

MAF and IAT sensor connector and “C37-26” terminal of 
ECM connector.

Is resistance below 3 

Ω

?

Go to Step 9.

“RED” wire is open or 
high resistance circuit.

Engine General Information and Diagnosis:  1A-78

DTC P0103: Mass Air Flow Circuit High Input

S5JB0A1104019

Wiring Diagram
Refer to “DTC P0101: Mass Air Flow Circuit Range / Performance”.

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 run it for 10 sec.
4) Check DTC and pending DTC.

9

MAF sensor output signal check
1) Connect connectors to MAF and IAT sensor and ECM 

with ignition switch turned OFF.

2) Measure voltage between “C37-26” and “C37-27” 

terminals of ECM connector referring to “Mass Air Flow 
(MAF) and Intake Air Temperature (IAT) Sensor On-
Vehicle Inspection in Section 1C”.

Is each value within specified range?

Substitute a known-
good ECM and recheck.

Faulty MAF and IAT 
sensor.

Step

Action

Yes

No

DTC detecting condition

Trouble area

DTC will be set when all of following conditions are detected for 0.5 seconds 
continuously.
• Engine is running
• Voltage of MAF sensor output is more than specified value for specified 

time continuously.

(1 driving cycle detection logic)

• Open or short in MAF sensor circuit
• MAF sensor
• ECM

1A-79 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

MAF sensor and its circuit check
1) Connect scan tool to DLC with ignition switch turned 

OFF.

2) Start engine and check MAF value displayed on scan 

tool. (Refer to “Scan Tool Data” for normal value.)

Is normal value indicated?

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

Go to Step 3.

3

MAF sensor power supply voltage check
1) Disconnect connector from MAF and IAT sensor with 

ignition switch tuned OFF.

2) Turn ON ignition switch, measure voltage between 

engine ground and “BLU/BLK” wire terminal of MAF and 
IAT sensor connector.

Is voltage 10 – 14 V?

Go to Step 4.

“BLU/BLK” wire is open 
circuit.

4

MAF sensor ground circuit check
1) Turn OFF ignition switch, measure resistance between 

“BLU” wire terminal of MAF and IAT sensor connector 
and engine ground.

Is resistance below 5 

Ω

?

Go to Step 6.

Go to Step 5.

5

Ground circuit check
1) Remove ECM from its bracket with ECM connectors 

connected.

2) Measure resistance between “C37-27” terminal of ECM 

connector and engine ground.

Is resistance below 5 

Ω

?

“BLU” wire is open or 
high resistance circuit.

ECM grounds “C37-58”, 
“C37-48”, “C37-30”, 
“C37-29” and/or “C37-
15” circuit are open or 
high resistance.
If wires are OK, 
substitute a known-
good ECM and recheck.

6

MAF sensor signal circuit check
1) Disconnect connectors from ECM with ignition switch 

turned OFF.

2) Measure voltage between “RED” wire terminal of MAF 

and IAT sensor connector and engine ground.

Is voltage 0 V?

Go to Step 7.

“RED” wire is shorted to 
other circuit.

7

MAF sensor output signal check
1) Connect connector to MAF and IAT sensor and ECM 

with ignition switch turned OFF.

2) Measure voltage between “C37-26” and “C37-27” 

terminal of ECM connector referring to “Mass Air Flow 
(MAF) and Intake Air Temperature (IAT) Sensor On-
Vehicle Inspection in Section 1C”.

Is each value within specified range?

Substitute a known-
good ECM and recheck.

Faulty MAF and IAT 
sensor.

Engine General Information and Diagnosis:  1A-80

DTC P0106: Manifold Absolute Pressure Range / Performance

S5JB0A1104020

Wiring Diagram

DTC Detecting Condition and Trouble Area

DTC Confirmation Procedure

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

°C (14 °F) to 80 °C (176 °F)

• Intake air temperature: –10 

°C (14 °F) to 70 °C (158 °F)

• Engine coolant temperature: 70 

°C (158 °F) to 150 °C (302 °F)

• Altitude (barometric pressure): 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)

 

1) Connect scan tool to DLC with ignition switch OFF.
2) Turn ON ignition switch and clear DTC using scan tool and warm up engine completely.
3) Run engine at idle speed for 1 min.
4) Check DTC and pending DTC.

E23

C37

3

4

18

19

5

6

7

10

11

17

20

47

46

49

50

51

21

22

52

16

25

9

24

14
29

55

57

54 53

59

60

58

2

26

27

28

15
30

56

48

32

31

34

35

36

37

40

42

39 38

44

45

43

41

33

1

12

13

23

8

3

4

18

19

5

6

7

10

11

17

20

47

46

49

50

51

21

22

52

16

25

9

24

14
29

55

57

54 53

59

60

58

2

26

27

28

15
30

56

48

32

31

34

35

36

37

40

42

39 38

44

45

43

41

33

1

12

13

23

8

4

1

2

3

GRY/RED

GRY/RED

5V

5V

C37-14  

C37-55  

C37-57  

RED/WHT

GRY/GRN

GRY/GRN

C37-15  

C37-29  
C37-48  

BLK/ORN

C37-58  

C37-30  BLK/ORN

BLK/YEL
BLK/YEL
BLK/YEL

I5JB0A110034-01

1. Manifold absolute pressure sensor

3. To other sensors

2. To electric load current sensor (for J20 engine) and A/C refrigerant pressure 

sensor (if equipped with A/C)

4. ECM

DTC detecting condition

Trouble area

• Difference between Max. manifold absolute pressure 

value and Min. manifold pressure value is less than 1.3 
kPa (0.19 psi) when engine running at idle speed.

• Difference between barometric pressure value and 

manifold pressure value is less than 33.3 kPa (4.83 psi) 
for 5 sec. at 2000 r/min. or more.

(2 driving cycle detection logic)

• Manifold absolute pressure sensor
• Manifold absolute pressure sensor vacuum passage
• Air intake system
• ECM