Suzuki Grand Vitara JB627. Manual - part 282

7B-44 Air Conditioning System: 

DTC B1520: Temperature Selector and/or Its Circuit Malfunction

S6JB0B7204019

DTC Detecting Condition and Trouble Area

DTC Confirmation Procedure

1) Connect scan tool to DLC with ignition switch turned OFF.
2) Turn ON ignition switch and clear DTC using scan tool.
3) Turn temperature selector to the light and left as far as it stops, repeat it 10 seconds.
4) Check DTC.

DTC Troubleshooting

10 Wire harness check

1) Measure voltage between “GRY/BLK” wire terminal of 

air flow control actuator connector and vehicle body 
ground with ignition switch turned ON.

Is voltage 0 V?

Go to Step 11.

“GRY/BLK” wire shorted 
to other circuit.

11 Position sensor circuit check

1) Check air flow control actuator position sensor circuit 

referring to Step 1 to Step 6 and Step 11 to Step 12 of 
“DTC B1512: Air Flow Control Actuator (Position 
Sensor) and/or Its Circuit Malfunction”.

Is it in good condition?

Go to Step 12.

Repair circuit.

12 Air flow control actuator check

1) Check air flow control actuator referring to “Air Flow 

Control Actuator Inspection”.

Is it in good condition?

HVAC control module 
faulty.

Air flow control actuator 
faulty.

Step

Action

Yes

No

DTC detecting condition

Trouble area

This DTC will be set when an internal malfunction is detected in the 
HVAC control module.
Temperature selector signal voltage is more than or less than 
specified value for specified time continuously.

HVAC control module (temperature selector)

Step

Action

Yes

No

1

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

OFF.

2) Turn ignition switch ON and clear DTC referring to “DTC 

Clearance”.

3) Turn ignition switch OFF position.
4) Turn ignition switch ON and check DTC referring to 

“DTC Check”.

Is there DTC B1520?

Go to Step 2.

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

2

HVAC control module terminal check
1) Remove HVAC control module referring to “HVAC 

Control Module Removal and Installation in Section 7A”.

2) Check for proper connection of HVAC control module 

connector at all terminals.

Is it in good condition?

Substitute a known-
good HVAC control 
module and recheck.

Repair faulty condition.

Air Conditioning System:  7B-45

DTC B1521: Blower Speed Selector and/or Its Circuit Malfunction

S6JB0B7204020

DTC Detecting Condition and Trouble Area

DTC Confirmation Procedure

1) Connect scan tool to DLC with ignition switch turned OFF.
2) Turn ON ignition switch and clear DTC using scan tool.
3) Turn blower speed selector to the light and left as far as it stops, repeat it 10 seconds.
4) Check DTC.

DTC Troubleshooting

DTC detecting condition

Trouble area

This DTC will be set when an internal malfunction is detected in the 
HVAC control module.
Blower speed selector signal voltage is more than and less than 
specified value for specified time continuously.

HVAC control module (blower speed selector)

Step

Action

Yes

No

1

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

OFF.

2) Turn ignition switch ON and clear DTC referring to “DTC 

Clearance”.

3) Turn ignition switch OFF position.
4) Turn ignition switch ON and check DTC referring to 

“DTC Check”.

Is there DTC B1521?

Go to Step 2.

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

2

HVAC control module terminal check
1) Remove HVAC control module referring to “HVAC 

Control Module Removal and Installation in Section 7A”.

2) Check for proper connection of HVAC control module 

connector at all terminals.

Is it in good condition?

Substitute a known-
good HVAC control 
module and recheck.

Repair faulty condition.

7B-46 Air Conditioning System: 

DTC B1530: Air Intake Control Actuator (Position Sensor) and/or Its Circuit Malfunction

S6JB0B7204021

Wiring Diagram

DTC Detecting Condition and Trouble Area

NOTE
When DTC B1502, B1503, B1511 and B1512 are indicated together, it is that “BLK/RED” wire circuit 
open.

 

DTC Confirmation Procedure

1) Connect scan tool to DLC with ignition switch turned OFF.
2) Turn ON ignition switch and clear DTC using scan tool.
3) Check DTC.

DTC Troubleshooting

12V

5V

M

5V

G52-22

G52-31

G52-32

G52-13

RED/WHT

G52-14

BLK/RED

GRN

WHT/GRN

ORN

[A]

2

3

4

1

13

14

22

32 31

I5JB0A720027-01

[A]: HVAC control module connector “G52” (harness side view)

3. To other actuators

1. HVAC control module

4. To other sensors

2. Air intake control actuator 

DTC Detecting Condition

Trouble Area

Air intake control actuator position sensor signal voltage is more than or less 
than specified value for specified time continuously.

• Air intake control actuator circuit
• Air intake control actuator
• HVAC control module

Step

Action

Yes

No

1

Position sensor power supply circuit check
1) Disconnect air intake control actuator connector with 

ignition switch turned OFF.

2) Check for proper connection to air intake control actuator 

at “RED/WHT”, “WHT/GRN” and “BLK/RED” wire 
terminals.

3) If OK, measure voltage between “RED/WHT” wire 

terminal of air flow control actuator connector and 
vehicle body ground with ignition switch turned ON.

Is voltage 4 – 6 V?

Go to Step 6.

Go to Step 2.

2

Position sensor power supply circuit check
1) Disconnect temperature control actuator connector with 

ignition switch turned OFF.

2) Measure voltage between “RED/WHT” wire terminal of 

air intake control actuator connector and vehicle body 
ground with ignition switch turned ON.

Is voltage 4 – 6 V?

Temperature control 
actuator faulty.

Go to Step 3.

Air Conditioning System:  7B-47

3

Position sensor power supply circuit check
1) Disconnect air flow control actuator connector with 

ignition switch turned OFF.

2) Measure voltage between “RED/WHT” wire terminal of 

air intake control actuator connector and vehicle body 
ground with ignition switch turned ON.

Is voltage 4 – 6 V?

Air flow control actuator 
faulty.

Go to Step 4.

4

Position sensor power supply circuit check
1) Disconnect connector from HVAC control module with 

ignition switch turned OFF.

2) Check for proper connection to HVAC control module 

connector at “G52-14”, “G52-22” and “G52-13” 
terminals.

3) If OK, measure resistance between “RED/WHT” wire 

terminal of air intake control actuator connector and 
“G52-14” terminal of HVAC control module connector.

Is resistance below 5 

Ω

?

Go to Step 5.

“RED/WHT” wire open 
or high resistance 
circuit.

5

Position sensor power supply circuit check
1) Measure resistance between “RED/WHT” wire terminal 

of air intake control actuator connector and vehicle body 
ground.

Is resistance infinity?

Go to Step 6.

“RED/WHT” wire 
shorted to ground 
circuit.

6

Position sensor power supply circuit check
1) Measure voltage between “RED/WHT” wire terminal of 

air flow control actuator connector and vehicle body 
ground with ignition switch turned ON.

Is voltage 0 V?

Go to Step 7.

“RED/WHT” wire 
shorted to other circuit.

7

Position sensor signal circuit check
1) Connect HVAC control module connector with ignition 

switch turned OFF.

2) Measure voltage between “WHT/GRN” wire terminal of 

air intake control actuator connector and vehicle body 
ground with ignition switch turned ON.

Is voltage 4 – 6 V?

Go to Step 11.

Go to Step 8.

8

Position sensor signal circuit check
1) Disconnect connector from HVAC control module with 

ignition switch turned OFF.

2) Measure resistance between “WHT/GRN” wire terminal 

of air intake control actuator connector and “G52-22” 
terminal of HVAC control module connector.

Is resistance below 5 

Ω

?

Go to Step 9.

“WHT/GRN” wire open 
or high resistance 
circuit.

9

Position sensor signal circuit check
1) Measure resistance between “WHT/GRN” wire terminal 

of air intake control actuator connector and vehicle body 
ground.

Is resistance infinity?

Go to Step 10.

“WHT/GRN” wire 
shorted to ground 
circuit.

Step

Action

Yes

No