B1CE113 - B1CE113 Left Outside Mirror Folding Motor Drive Circuit Open Circuit Fault

B1CE113 Fault Depth Definition

DTC B1CE113 is defined by the system as "Left Outer Rearview Mirror Folding Motor Drive Circuit Open Fault". In the vehicle's overall electrical architecture, this diagnostic code reflects a physical state anomaly of the communication link between the control unit (Domain Control Unit) and the actuator. The core technical meaning of this fault code is: when the Domain Control Unit sends drive commands to the left outer rearview mirror folding adjustment motor, the monitoring circuit fails to detect the expected load current feedback. From a system principle perspective, this usually indicates that the circuit is in a high-impedance or open state, causing the control unit to be unable to confirm motor execution of folding action through closed-loop feedback. This code is mainly used in the vehicle network protocol to identify electrical integrity failure of the drive circuit, prompting the system to validate health on physical connection paths and controller logic.

Common Fault Symptoms

When DTC B1CE113 is triggered and stored in the control unit's memory, specific phenomena observable by the driver or maintenance technician typically include:

• Function Execution Failure: The left outer rearview mirror completely fails to respond to folding commands, manifesting as inability to perform electric folding via car key remote, body control module button, or voice/touch instructions in setup menus.
• Status Feedback Loss: When vehicle power is in "ON Power" and the system attempts to activate the left outer rearview mirror folding motor working mode, no mechanical action response occurs at the actuator end.
• Instrument Indication Anomaly: Some vehicle platforms may display that the rearview mirror control function is disabled or relevant fault warning icons exist on the instrument panel or central multimedia system (depending on software mapping logic).

Core Fault Cause Analysis

Regarding the triggering mechanism of B1CE113 fault code, its root cause can be analyzed according to electrical system architecture divided into the following three technical dimensions:

• Hardware Component Failure (Motor End): The internal coil of the left outer rearview mirror folding adjustment motor occurs open circuit, armature stuck causing inability to attract/engage, or internal drive IC failure. Such situations lead to current being unable to flow through the motor winding when the control unit issues commands, thus being judged as drive circuit open.
• Wiring and Connector Failure (Physical Connection): The harness between Domain Control Unit and left outer rearview mirror folding adjustment motor has insulation layer damage, conductor breakage, or connector pins backing out, oxidizing/corrosion causing poor contact. These physical connection interruptions directly cut the current transmission path.
• Controller Logic Anomaly (Logic Operation): Power monitoring module or fault diagnosis algorithm inside Left Domain Controller has logic errors. Even if circuit is intact, if controller cannot correctly sample voltage and current data to calculate normal load status, it may erroneously trigger this open circuit fault code.

Technical Monitoring and Trigger Logic

System enters this fault monitoring mode and records DTC B1CE113, needs to strictly meet the following preset electrical and environmental operating conditions:

• Power State Monitoring: Vehicle power must be in Ignition ON mode, ensuring control unit is powered on and activates relevant diagnostic circuits.
• Voltage Window Limitation: Controller supply voltage must stay stable between $9V$~$16V$. If voltage exceeds this range, system may enter low-power protection or close some monitoring functions, unable to trigger this specific fault code.
• Operating Condition Execution Requirement: Diagnosis only performs dynamic monitoring in Left Outer Rearview Mirror Folding Motor working mode, meaning control unit has sent clear folding drive commands.
• Current Threshold Judgment Logic: During drive motor command issuing period, system continuously collects drive motor current signals. If continuous collection shows drive current is 0 (or matches open circuit threshold), and state duration reaches 3s, control system will immediately judge as circuit open fault. Once all above conditions are met, fault counter increments and finally locks DTC B1CE113.