Suzuki Grand Vitara JB416 / JB420 / JB419. Manual - part 77

1A-255 Engine General Information and Diagnosis: For Petrol Engine Model

Step

Action

Yes

No

1

Reception data check from BCM
1) Connect scan tool to DLC with ignition switch turned 

OFF.

2) Turn ON ignition switch.
3) Check DTC for reception data from BCM.

Is there DTC P1678?

Go to applicable DTC 
diag. flow.

Go to Step 2.

2

DTC check of HVAC control module
1) Check HVAC control module for DTC.

Is there DTC(s)?

Go to applicable DTC 
diag. flow.

Go to Step 3.

3

A/C switch signal circuit check
1) Start engine and select “DATA LIST” mode on scan tool.
2) Check A/C switch signal under following conditions 

respectively.

A/C switch signal 
Engine running, A/C switch OFF: OFF
Engine running, A/C switch ON and blower speed 
selector turned 1st position or more: ON

Is check result satisfactory?

Go to Step 4.

Check HVAC control 
module and its circuit.

4

DTC check of ECT sensor circuit
1) Check ECM for DTC of ECT sensor circuit.

Is there DTC P0116, DTC P0117 or DTC P0118?

Go to applicable DTC 
diag. flow.

Go to Step 5.

5

Radiator cooling fan control system check

Is radiator cooling fan started when A/C and blower speed 
selector switch are turned ON with engine running?

Go to Step 11.

Go to Step 6.

6

Radiator cooling fan control circuit check
1) Check DTC with scan tool.

Is DTC P0480 displayed?

Go to “DTC P0480: Fan 
1 (Radiator Cooling 
Fan) Control Circuit: For 
Petrol Engine Model”.

Go to Step 7.

7

Evaporator temperature sensor check
1) Check evaporator temperature sensor referring to “A/C 

Evaporator Temperature Sensor Inspection in Section 
7B”.

Is resistance within specification?

Go to Step 8.

Faulty evaporator 
temperature sensor.

8

DTC check of A/C refrigerant pressure sensor circuit
1) Connect scan tool to DLC with ignition switch turned 

OFF.

2) Turn ON ignition switch.
3) Check ECM for DTC of A/C refrigerant pressure sensor 

circuit.

Is there DTC P0532 or DTC P0533?

Go to applicable DTC 
diag. flow.

Go to Step 9.

9

A/C refrigerant pressure sensor voltage check
1) Check A/C refrigerant pressure sensor voltage referring 

to “Inspection of ECM and Its Circuits: For Petrol Engine 
Model”.

Is voltage within specified value?

Go to Step 10.

Check amount of 
refrigerant. If OK, 
replace A/C refrigerant 
pressure sensor.

Engine General Information and Diagnosis: For Petrol Engine Model 1A-256

10 Radiator cooling fan check

1) Check radiator cooling fan referring to “Radiator Cooling 

Fan Motor On-Vehicle Inspection: For Petrol Engine 
Model in Section 1F”.

Is check result satisfactory?

Radiator cooling fan 
drive circuit malfunction. 
If circuit is OK, go to 
Step 7.

Replace radiator cooling 
fan motor.

11 A/C compressor control system check

Is A/C compressor started when A/C and blower speed 
selector switch are turned ON with engine running?

A/C system is in good 
condition.

Go to Step 12.

12 A/C compressor relay circuit check

1) Measure voltage between “E23-49” wire terminal of 

ECM connector and vehicle body ground under following 
conditions respectively.

Voltage between “E23-49” terminal of ECM 
connector and ground
While engine running and A/C switch turned OFF: 10 
– 14 V
While engine running, A/C and blower speed 
selector switch turned ON: 0 – 1 V

Is check result satisfactory?

Go to Step 13.

Go to Step 14.

13 A/C compressor relay check

1) Check A/C compressor relay referring to “A/C 

Compressor Relay Inspection in Section 7B”.

Is it in good condition?

A/C compressor drive 
circuit malfunction.

Replace A/C 
compressor relay.

14 A/C compressor relay circuit check

1) Remove A/C compressor relay with ignition switch 

turned OFF.

2) Turn ON ignition switch, measure voltage between “YEL/

GRN” wire terminal of A/C compressor relay connector 
and vehicle body ground.

Is voltage 10 –14 V?

Go to Step 15.

“YEL/GRN” wire is open 
circuit.

15 A/C compressor relay check

1) Check A/C compressor relay referring to “A/C 

Compressor Relay Inspection in Section 7B”.

Is it in good condition?

“PNK” wire is open 
circuit. If OK, substitute 
a known-good ECM and 
recheck.

Replace A/C 
compressor relay.

Step

Action

Yes

No

1A-257 Engine General Information and Diagnosis: For Petrol Engine Model

Electric Load Signal Circuit Check

S6JB0A1114086

Wiring Diagram

WHT/BLU

BLU/ORN

WHT/RED

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

E23-4

E23-19

1

RED

WHT

E03-12

E03-6

WHT/BLU

WHT/RED

E03-8

E03-10

RED

WHT

G31-3

G31-1

2

C37-7

3

5

12V

4

I5JB0A110104-02

1. ECM

3. ABS / ESP

® control module

5. Electric load signal (blower motor 

signal, rear defogger signal, headlight 
signal and A/C switch signal), etc.

2. BCM

4. PSP switch

Engine General Information and Diagnosis: For Petrol Engine Model 1A-258

Troubleshooting

NOTE

• Before performed troubleshooting, be sure to read the “Precautions of ECM Circuit Inspection: For 

Petrol Engine Model”.

• 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: For 
Petrol Engine Model”.

 

Step

Action

Yes

No

1

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

OFF.

2) Turn ON ignition switch and check DTC.

Is there DTC P1674 and/or P1678?

Go to applicable DTC 
diag. flow.

Go to Step 2.

2

Electric load signal circuit check
1) Start engine and select “DATA LIST” mode on scan tool.
2) Check electric load signal under following conditions 

respectively.

A/C switch signal
Engine running, A/C switch OFF: OFF
Engine running, A/C switch ON and blower speed 
selector turned 1st position or more: ON

Blower fan signal
Engine running, blower speed selector OFF: OFF
Engine running, blower speed selector 5th position 
or more: ON

PSP signal
Engine running, steering wheel to neutral position: 
OFF
Engine running, turning steering wheel to the right 
or left as far as it stops: ON

Electric load signal
Engine running, rear defogger switch or headlight 
switch OFF: OFF
Engine running, rear defogger switch or headlight 
switch ON: ON

Is check result satisfactory?

Electric load signal 
circuit is in good 
condition

Check defective signal 
circuit.