Suzuki Grand Vitara JB416 / JB420 / JB419. Manual - part 392
7B-59 Air Conditioning System:
DTC B1552: Serial Communication Circuit Malfunction
S6JB0A7204025
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
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.