C113016 - C113016 Left Side Actuator Supply Under Voltage Fault

Fault Deep Definition

In the architecture of the Electric Parking Brake (EPB) control system, C113016 represents a specific Diagnostic Trouble Code (DTC), used to identify system abnormalities under the specific condition of Left Actuator Power Under-voltage. This DTC is generated by internal integrated logic within the Electronic Parking Controller, with its core monitoring target being the power supply status of the Left Caliper Motor.

During the closed-loop control process of executing electronic parking braking, the control unit strictly verifies the power supply quality of the left actuator through a real-time feedback loop. The term "under-voltage" means that at the moment the system requests activation or maintenance of state, the actual voltage supplied to the Left Actuator fails to maintain within the normal operating threshold range. This definition covers the energy transmission integrity in the complete power supply path from the battery positive terminal, through the wiring harness, to the actuator port. Any physical factors causing the power rail voltage to drop below the logic determination standard will trigger the storage and output of this code.

Common Fault Symptoms

When the system determines that C113016 fault is established, vehicle user experience and dashboard feedback will present the following specific manifestations:

• Left Parking Brake Failure: When the driver attempts to pull up or press the electronic parking switch, the vehicle cannot normally execute the locking instruction, and the expected mechanical fixation effect cannot be realized.
• Abnormal Dynamic Response: During starting or stopping processes, the functional module involving left-rear wheel braking may appear in an unreliable response state, even accompanied by relevant system warning light prompts (such as the braking system warning light).
• Driving Mode Restricted: To prevent safety risks, the electronic parking controller may enter a protection mode, prohibiting actuator actions under high current load, resulting in restricted manual release or locking functions.

Core Fault Cause Analysis

For root cause troubleshooting of C113016 fault code, technical logic can be summarized into three dimensions of hardware or control issues:

• Hardware Components (Motor Itself): Electrical defects such as coil short circuits or drive chip failure may exist within the left rear caliper motor assembly, causing power supply voltage to be unable to conduct stably to the actuation mechanism, thereby triggering power supply terminal voltage monitoring anomalies.
• Wiring and Connectors (Physical Connection): Failures exist in the wiring harness or connector between the Electronic Parking Controller and the left actuator. This may include ground/positive short circuits due to wire insulation damage, poor contact of pins, or high resistance caused by oxidation/corrosion of terminals, causing excessive voltage drop under load and meeting "under-voltage" criteria.
• Controller (Logic Operation): Hardware anomalies such as power management module or A/D conversion sampling circuit within the Electronic Parking Controller may falsely report low voltage signals. Logic operation errors within the control unit software could also erroneously judge a normal voltage state as under-voltage, triggering fault code storage.

Technical Monitoring & Trigger Logic

The system's judgment on C113016 follows strict time window and operating condition matching principles. Its monitoring and trigger mechanisms are as follows:

• Monitoring Target: The electronic parking controller continuously collects the power supply voltage signal at the left actuator port and compares it with the normal reference voltage stored internally.
• Specific Operating Conditions: Fault is activated only when satisfying the following dual logic conditions:
  1. Start Switch Placed in ON Position: Vehicle power system is energized, control unit is in working mode.
  2. Electronic Parking Brake Switch Pulled or Pressed: Driver issues a clear lock/unlock instruction, actuator enters drive mode.
• Trigger Logic: Once the left actuator power supply voltage falls below the preset normal range lower limit under these conditions, the controller will immediately record fault frame data and illuminate relevant indicator lights and store DTC codes after meeting fault confirmation conditions. This logic ensures that occasional fluctuations during static standby do not lead to false judgment, only locking onto real abnormalities under load conditions.