B110C09 - B110C09 PM2.5 Sensor Laser Diode Failure

Fault Depth Definition

Fault Code B110C09 marks an abnormality in the core sensing unit of the vehicle air quality monitoring system. The PM2.5 Rapid Tester, as a key component for interior environment perception, operates based on a stable light beam emitted by an integrated laser diode inside, capturing physical characteristics of suspended particles in the air through optical scattering technology in real-time. When this fault code is recorded by the system, it indicates that the control unit detects that the laser diode cannot establish an effective optoelectronic feedback loop. This is not only the failure of a single component but also represents a logical interruption of the entire particulate matter concentration data acquisition chain, resulting in the vehicle's inability to accurately quantify interior air cleanliness.

Common Fault Symptoms

When the vehicle system stores fault code B110C09, drivers and passengers may perceive the following driving experience or instrument feedback issues:

• Data stagnation, disappearance, or display of error codes in the air quality display area on the instrument cluster or information entertainment system.
• The vehicle cabin air purification system cannot enter automatic adjustment mode, and air volume control no longer adjusts with air quality changes.
• PM2.5 Rapid Tester function failure; relevant system status indicator lights may light up the fault warning lamp.
• Options regarding environmental monitoring in the vehicle settings menu display as "Unavailable" or a gray state.

Core Fault Cause Analysis

Based on system architecture and data flow logic, the causes of this fault can be summarized into the following three technical dimensions:

• Hardware Components: Physical damage to the laser diode inside the PM2.5 Rapid Tester, life expiration leading to decay in luminous efficiency, or dust contamination obstructing light transmission in the optical sampling chamber.
• Wiring/Connectors: Abnormalities in physical connection between the sensor module and Body Control Unit, including open circuit in power supply wire, poor grounding, or signal transmission line contact resistance being too high.
• Controller: Internal logic judgment anomaly within the control unit responsible for processing sensor data. When received signal characteristics cannot pass validation algorithms, it is determined as an untrustworthy component.

Technical Monitoring and Trigger Logic

The system performs real-time verification of sensor status through specific diagnostic routines to ensure data reliability:

• Monitoring Target: Focus on monitoring the drive status of the laser diode and optical signal reception intensity, ensuring the optical link is within normal working range.
• Fault Trigger Condition: When the start switch is in the ON position, the system executes the power-on self-check program, at which time initialization test is performed on the sensor core components.
• Judgment Logic: If during the self-check process, the control unit does not receive an effective response signal from the laser diode, or the signal characteristics do not conform to preset electrical characteristic standards, then set fault condition PM2.5 Rapid Tester Laser Diode Failure, and immediately store fault code B110C09.