Suzuki Grand Vitara JB416 / JB420. Manual — part 31

1A-73 Engine General Information and Diagnosis:

DTC P0101: Mass Air Flow Circuit Range / Performance

S5JB0A1104017

Wiring Diagram

10 HO2S heater control circuit check

1) Disconnect connector from ECM with ignition switch

turned OFF.

2) Check for proper connection of HO2S-2 heater circuit

terminal to ECM connector.

3) If connection are OK, measure wire resistance of sensor

heater control circuit at ECM connector between ECM to
HO2S-2.

Is measured wire resistance lower than 1

Ω

?

Go to Step 11.

Repair or replace
defective wire circuit.

11 HO2S-2 heater circuit check

1) Measure insulation resistance between control terminal

of HO2S-2 heater at ECM connector and vehicle body
ground.

Is measured resistance infinity?

Substitute a known
good ECM and recheck.

Repair or replace short
wire.

Step

Action

Yes

No

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

BLK/WHT

BLU/BLK

BLU/BLK

WHT/GRN

BLK/RED

BLK/RED

BLK/RED

BLK/YEL

BLU

12V

5V

5V

2

3

4

E23-29

E23-1

E23-60

BLU/BLK

E23-16

LT GRN

GRY/GRN

GRY/GRN

1

BLU/BLK

C37-25

C37-57

5

BLU

RED

C37-26

C37-27

C37-15

C37-29
C37-48

BLK/ORN

C37-58

C37-30 BLK/ORN

BLK/YEL
BLK/YEL
BLK/YEL

I5JB0A110033-01

1. MAF and IAT sensor

3. Main relay

5. To other sensors

2. Ignition switch

4. ECM

Engine General Information and Diagnosis: 1A-74

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

• Road test should be carried out by 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 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) 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. (ECT approx. 90 – 95

°C, 194 – 203 °F)

4) Drive vehicle with engine speed: more than 2500 rpm for 1 min.
5) Increase vehicle speed to 80 km/h (45 mile/h) at 5th gear or D range.
6) Release accelerator pedal to decrease vehicle speed to 40 km/h (25 mile/h).
7) Stop vehicle and run it idle for 1 min.
8) 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

• MAF volume is greater than 25 g/sec even if engine

revolution is less than 900 rpm and intake manifold
pressure is less than 45 kPa (6.35 psi) with TP less than
3.0

°.

• MAF volume is lower than 4 g/sec even if engine revolution

is more than 2500 rpm and intake manifold pressure is
more than 50 kPa (7.25 psi) with TP more than 15

°.

(2 driving cycle detection logic)

• Air intake system (clog or leakage)
• MAF sensor circuit
• MAF sensor
• TP sensor and/or its circuit
• MAP sensor and/or its circuit
• 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

Visual inspection
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.

1A-75 Engine General Information and Diagnosis:

3

MAF sensor and its circuit check
1) With ignition switch turned 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 each value within specified range?

Go to Step 11.

Go to Step 4.

4

MAF sensor output voltage check
1) Turn OFF ignition switch.
2) Remove ECM from its bracket with ECM connectors

connected.

3) 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?

Poor “C37-26” and/or
“C37-27” terminal
connection.
If OK, substitute a
known-good ECM and
recheck.

Go to Step 5.

5

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 (2) of MAF
and IAT sensor connector (1).

Is voltage 10 – 14 V?

Go to Step 6.

“BLU/BLK” wire is open
circuit.

6

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 8.

Go to Step 7.

7

Ground circuit check
1) Measure resistance between “C37-27” terminal of ECM

connector and vehicle body 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 is open or
high resistance.
If wires are OK,
substitute a known-
good ECM and recheck.

Step

Action

Yes

No

I4RS0A110020-01

Engine General Information and Diagnosis: 1A-76

DTC P0102: Mass Air Flow Circuit Low Input

S5JB0A1104018

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.

8

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

turned OFF.

2) Turn ON ignition switch, measure voltage between

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

Is voltage 0 V?

Go to Step 9.

“RED” wire is shorted to
others circuit.

9

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

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

Is resistance infinity?

Go to Step 10.

“RED” wire is shorted to
ground circuit.

10 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

?

Faulty MAF and IAT
sensor.

“RED” wire is open or
high resistance circuit.

11 Is DTC P2135 detected?

Go to “DTC P2135:
Throttle Position Sensor
(Main / Sub) Voltage
Correlation”.

Go to Step 12.

12 Is DTC P0106 displayed?

Go to “DTC P0106:
Manifold Absolute
Pressure Range /
Performance”.

Substitute a known-
good ECM and recheck.

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 less than specified

value for specified time continuously.

(1 driving cycle detection logic)

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