Suzuki Grand Vitara JB416 / JB420. Manual - part 274

7A-2 Heater and Ventilation: 

Body Ventilation Construction

S5JB0A7101002

The body ventilation system of this vehicle has a fresh 
air intake (1) located at the cowl top panel. When fresh 
air intake air selector is at FRE position (fresh), 
ventilating air is drawn into the interior from the cowl 
center garnish and drawn out from the ventilator outlet 
(2) provided at each side body outer panel (both right 
and left side).

On-Board Diagnostic System Description (for 
Vehicle without A/C)

S5JB0A7101004

HVAC control module (for vehicle without A/C) detects 
malfunction, which may occur in the following area. 
When HVAC control module detects any malfunction, the 
REC (recirculation) indicator lamp (4) flashes on and off 
continuously after turning ignition switch to ON position.
• ECT sensor
• CMP sensor
• Wheel speed sensor
• Temperature control actuator
• Air flow control actuator
• Air intake control actuator
• Temperature selector of HVAC control module
• Blower speed selector of HVAC control module
• Serial communication line
• CAN communication line
DTC can be checked by either one of the following ways.
• DTC can be checked by using SUZUKI scan tool (2) 

connected to DLC (1).

• Without using SUZUKI scan tool, DTC can be 

checked by reading the flashing pattern of both the 
FRE (fresh) indicator lamp (3) and the REC 
(recirculation) indicator lamp (4).

• Pressing DEF (defogger) switch (5) alternates display 

of current DTC and history DTC.

• DEF indicator lamp (6) remains off when display is in 

current DTC and it lights up when display is in history 
DTC.

HVAC Control System Description (for Vehicle 
without A/C)

S5JB0A7101005

For CAN communication system, refer to description on 
“CAN Communication System Description in Section 
1A”.
When following data are sent from control modules to 
BCM through CAN communication, they are sent from 
BCM to HVAC control module through serial 
communication line.
• Engine coolant temperature
• Engine Speed
• Wheel speed (Vehicle speed)
HVAC control module has a function to make initial 
settings of temperature control actuator, air intake 
actuator and air flow actuator.
For vehicle without A/C, HVAC control module uses 
engine speed signal so that temperature control 
actuator, air intake actuator and air flow actuator can 
make initial setting for door position.
Initial settings of actuators are automatically made when 
engine is started for the first time after battery is 
connected.
When initial settings are made, each actuator is forced to 
operate for about 15 seconds continuously.

2

1

2

I5JB0A710002-03

3

4

5

6

1

2

I5JB0A710004-04

Heater and Ventilation:  7A-3

Schematic and Routing Diagram

Heater and Ventilation Wiring Circuit Diagram

S5JB0A7102001

Refer to “A/C System Wiring Circuit Diagram in Section 7B”.

Electronic Control Input / Output Diagram (for Vehicle without A/C)

S5JB0A7102003

Temperature selector

MODE (air flow) selector

Blower speed selector

Air intake selector

Wheel 
speed 
sensor

Blower motor controller

Temperature control actuator

Air flow control actuator

Air intake control actuator

BCM

ABS control module

Data link connector

HVAC control module

CPU

ECT sensor

ECM

CMP sensor

*

*

I5JB0A710003-05

*: CAN communication

7A-4 Heater and Ventilation: 

Component Location

Electronic Components Location for Heater (for Vehicle without A/C)

S5JB0A7103001

NOTE
The figure shows left-hand steering vehicle. For right hand steering vehicle, parts with (*) are installed 
at the opposite side.

 

2

3

1*

4*

5*

18

6

17

19

8

15

16

10

9

14

7

11

12

13

I5JB0A710005-07

1. Air intake control actuator

8. “DEF / FOOT” switch

15. “REC” indicator lamp

2. Temperature control actuator

9. “FOOT” switch

16. “FRE” indicator lamp

3. Air flow control actuator

10. “BI-LEVEL” switch

17. MODE selector

4. Blower motor

11. “VENT” switch

18. HVAC control module (for vehicle without A/C)

5. Blower motor controller

12. Theft deterrent light

19. “DEF” indicator lamp

6. Temperature selector

13. Blower speed selector / Air intake selector

7. “DEF” switch

14. Rear defogger switch

Heater and Ventilation:  7A-5

Diagnostic Information and Procedures

Heater and Ventilation System Check

S5JB0A7104009

Step

Action

Yes

No

1

)

 Customer complaint analysis

1) Perform “Customer complaint analysis”.

Was customer complaint analysis performed?

Go to Step 2.

Perform customer 
complaint analysis.

2

)

 DTC check

1) Perform “DTC check”.

Is there any DTC code?

Go to Step 3.

Go to Step 4.

3

)

 Troubleshooting malfunction

1) Perform “Troubleshooting malfunction”.

Is there any faulty condition?

Repair or replace 
malfunction part, and go 
to Step 7.

Go to Step 5.

4

)

 Visual inspection

1) Perform “Visual inspection”.

Is there any faulty condition?

Repair or replace 
malfunction part.

Go to Step 5.

5

)

 Perform heater and ventilation system symptom 

diagnosis
1) Inspect and repair referring to “Heater and Ventilation 

Symptom Diagnosis”.

Is there any faulty condition?

Repair or replace 
malfunction part, and go 
to Step 7.

Go to Step 6.

6

)

 Check for intermittent problem

1) Check for intermittent troubles referring to “Intermittent 

and Poor Connection Inspection in Section 00”.

Is there any faulty condition?

Repair or replace 
malfunction part, and go 
to Step 7.

Go to Step 7.

7

)

 Final confirmation test

1) Perform “Final confirmation test”.

Is there any malfunction code?

Go to Step 4.

Heater and ventilation 
system is in good 
condition.