Suzuki Grand Vitara JB627. Manual — part 284

7B-52 Air Conditioning System:

DTC B1551: Serial Communication Circuit Malfunction

S6JB0B7204024

Wiring Diagram

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) Check DTC.

DTC Troubleshooting

5V

G52-10

G30-5

YEL/RED

[A]

2

1

3

10

I5JB0A720029-01

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

2. BCM

1. HVAC control module

3. Information display

DTC detecting condition

Trouble area

Serial communication signal is more than or less than specified value for
specified time continuously.

• Serial communication line of BCM
• BCM
• Information display
• HVAC control module

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) Disconnect connector from information display with

ignition switch turned OFF.

4) Turn ignition switch ON and check DTC referring to

“DTC Check”.

Is there DTC B1551?

Go to Step 2.

Information display
faulty.

2

Wire harness check
1) Disconnect connectors from BCM and HVAC control

module.

2) Measure resistance between “G30-5” terminal of BCM

connector and “G52-10” terminal of HVAC control
module connector.

Is resistance below 5

Ω

?

Go to Step 3.

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

3

Wire harness check
1) Measure resistance between “G52-10” terminal of HVAC

control module connector and vehicle body ground.

Is resistance infinity?

Go to Step 4.

“YEL/RED” wire shorted
to ground circuit.

Air Conditioning System: 7B-53

DTC B1552: Serial Communication Circuit Malfunction

S6JB0B7204025

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) Check DTC.

DTC Troubleshooting

4

Wire harness check
1) Measure voltage between “G52-10” terminal of HVAC

control module connector and vehicle body ground with
ignition switch turned ON.

Is voltage 0 V?

Go to Step 5.

“YEL/RED” wire shorted
to other circuit.

5

Serial communication signal check
1) Connect connectors to BCM and HVAC control module.
2) Using oscilloscope, check that serial communication

signal at “G30-5” is outputted referring to “Voltage
Check” in “Inspection of BCM and Its Circuits in Section
10B”.

Is serial communication signal outputted at “G30-5” terminal
of BCM connector?

HVAC control module
faulty.

BCM (included in
junction block
assembly) faulty.

Step

Action

Yes

No

DTC detecting condition

Trouble area

Data received by HVAC control module from BCM is erroneous continuously. • BCM

• HVAC control module

Step

Action

Yes

No

1

Serial communication signal data check
1) Connect scan tool to DLC with ignition switch turned

OFF.

2) Start engine and select “DATA LIST” mode on scan tool.
3) Check “Refrigerant Pressure”, “Vehicle Speed”, “Coolant

Temp” and “Outside Air Temp” varies displayed on scan
tool.

Is displayed each varies described varies in “Scan Tool
Data”?

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

Go to Step 2.

2

Serial communication signal check
1) Connect connectors to BCM and HVAC control module.
2) Using oscilloscope, check that serial communication

signal at “G30-5” is outputted referring to “Voltage
Check” of “Inspection of BCM and Its Circuits in Section
10B”.

Is serial communication signal outputted at “G30-5” terminal
of BCM connector?

HVAC control module
faulty.

BCM (included in
junction block
assembly) faulty.

7B-54 Air Conditioning System:

DTC B1553: CAN Communication Circuit Malfunction

S6JB0B7204026

DTC Detecting Condition and Trouble Area

DTC Troubleshooting

DTC B1556: Camshaft Position (CMP) Sensor and/or Its Circuit Malfunction

S6JB0B7204027

DTC Detecting Condition and Trouble Area

DTC Troubleshooting

DTC B1557: Wheel Speed Sensor and/or Its Circuit Malfunction

S6JB0B7204028

DTC Detecting Condition and Trouble Area

DTC Troubleshooting

DTC detecting condition

Trouble area

HVAC control module receives error code from BCM continuously.

• CAN communication circuit
• BCM
• ECM
• HVAC control module

Step

Action

Yes

No

1

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

OFF.

2) Check ECM and BCM for DTC.

Is there DTC(s)?

Go to applicable DTC
diag. flow.

Substitute a known-
good HVAC control
module and recheck.

DTC detecting condition

Trouble area

HVAC control module receives error code from BCM continuously.

• CMP sensor circuit
• CMP sensor
• HVAC control module

Step

Action

Yes

No

1

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

OFF.

2) Check ECM for DTC.

Is there DTC P0340?

Go to applicable DTC
diag. flow.

Substitute a known-
good HVAC control
module and recheck.

DTC detecting condition

Trouble area

HVAC control module receives error code from BCM continuously.

• Wheel speed sensor circuit
• ABS or ESP

® control module

• Wheel speed sensor
• HVAC control module

Step

Action

Yes

No

1

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

OFF.

2) Check ABS or ESP

® for DTC.

Is there DTC C1021, C1022 / C1025, C1026 / C1031,
C1032 / C1035, C1036?

Go to applicable DTC
diag. flow.

Substitute a known-
good HVAC control
module and recheck.

Air Conditioning System: 7B-55

DTC B1561: Engine Coolant Temperature Sensor and/or Its Circuit Malfunction

S6JB0B7204029

DTC Detecting Condition and Trouble Area

DTC Troubleshooting

DTC B1562: Outside Air Temperature Sensor and/or Its Circuit Malfunction

S6JB0B7204030

DTC Detecting Condition and Trouble Area

DTC Troubleshooting

DTC B1563: A/C Refrigerant Pressure Sensor and/or Its Circuit Malfunction

S6JB0B7204031

DTC Detecting Condition and Trouble Area

DTC Troubleshooting

DTC detecting condition

Trouble area

HVAC control module receives error code from BCM continuously.

• ECT sensor circuit
• ECT sensor
• HVAC control module

Step

Action

Yes

No

1

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

OFF.

2) Check ECM for DTC.

Are there DTC P0116, P0117 or P0118?

Go to applicable DTC
diag. flow.

Substitute a known-
good HVAC control
module and recheck.

DTC detecting condition

Trouble area

HVAC control module receives error code from BCM continuously.

• Outside air temperature sensor

circuit

• Outside air temperature sensor
• HVAC control module

Step

Action

Yes

No

1

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

OFF.

2) Check BCM for DTC.

Are there DTC B1141, B1142 or B1143?

Go to applicable DTC
diag. flow.

Substitute a known-
good HVAC control
module and recheck.

DTC detecting condition

Trouble area

HVAC control module receives error code from BCM continuously.

• A/C refrigerant pressure sensor

circuit

• A/C refrigerant pressure sensor
• HVAC control module

Step

Action

Yes

No

1

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

OFF.

2) Check ECM for DTC.

Are there DTC P0532 or P0533?

Go to applicable DTC
diag. flow.

Substitute a known-
good HVAC control
module and recheck.