U111982 - U111982 RCR_R Counter Error

Fault Depth Definition

U111982 RCR_R Counter Error is a high-level control unit fault code defined in the vehicle Adaptive Cruise Control System (ACC) internal diagnostic system. This fault code mainly involves data processing and synchronization mechanisms of the Right Corner Radar System. In the system's operational logic, the controller is responsible for collecting and processing pulse signals and digital counting instructions from sensor loops in real time to build precise distance feedback loops. When the RCR_R Counter malfunctions, it means the control unit detected a mismatched logical deviation when monitoring the radar system's timing, position updates, or internal register status. This fault is directly linked to the adaptive cruise function's core monitoring module; once triggered, the system determines that current distance measurement accuracy cannot be guaranteed and forces intervention of safety strategies. This code is not merely a single signal loss but a critical indicator of failed integrity checks in data exchange between the radar controller and the main control unit.

Common Fault Symptoms

When U111982 RCR_R Counter Error is activated, the vehicle electronic control network will record relevant status and feedback system abnormality to drivers through the following forms:

• Adaptive Cruise Control System Function Failure: ACC auxiliary driving functions will be software locked closed, warning icons indicating ACC unavailable may appear on the instrument panel or display screen.
• Auxiliary Driving Functions Restricted: Lane keeping or dynamic distance maintenance functions may be deactivated along with it, and the vehicle returns to basic power control mode.
• Instrument Panel Warning Prompt: Some models will pop up fault prompt information related to the radar system in the Driver Information Center (DIC) or instrument panel, prompting users to undergo service inspection.

Core Fault Cause Analysis

Based on fault code logic and physical architecture, this abnormality can be summarized as potential sources from the following three dimensions, which require logical localization by professional diagnostic equipment:

• Hardware Component Dimension: Right Corner Radar System Failure. This is the physical component directly triggering this counter error, usually manifested as unstable internal circuit in radar sensor module, damaged chip counting unit or signal acquisition front-end (such as antenna coupler) physical damage, leading to inability to produce standard feedback pulses conforming to expectations.
• Line/Connector Dimension: Insufficient physical connection reliability. Includes whether communication wiring between Right Corner Radar System and controller has pin corrosion, open circuit, short circuit phenomena, or if connectors are not fully locked, causing instantaneous interference or counting signal packet loss during signal transmission.
• Controller Dimension: Controller logic operation deviation. Refers to logical dead loops, memory overflow, or configuration parameter errors in internal software when control unit performs counter refresh, state machine jump or data parsing algorithms, unable to correctly determine monitoring timer status.

Technical Monitoring and Trigger Logic

The determination of this fault code follows strict timing monitoring and electrical condition verification, and must satisfy all the following trigger conditions simultaneously to write to fault storage:

• Voltage Environment Constraint: System only monitors when controller is within normal operating voltage range, at which time controller voltage range is $9V$~$16V$. If voltage exceeds this threshold, system enters low-power or protection state, not recording this code.
• Start-up Timing Logic: Must start monitoring counter effectiveness after vehicle power-on initialization $3s$. This ensures internal initialization process of control unit is complete and all hardware nodes are ready.
• Continuous Failure Judgment: Any monitoring timer error must be failed 3 times continuously to trigger fault code. System does not judge based on single instantaneous error, but locks as deterministic fault by inability to resolve abnormal state after multiple attempts to reset or re-verify.
• Network Status Limitation: Public CAN bus is not entering busoff state. This indicates communication link between controller and other vehicle nodes (such as gateway, powertrain modules) remains active, excluding false alarms caused by entire network paralysis.
• System Mode Constraint: Factory mode must be turned off. Fault codes can only be formally recorded in non-factory calibration modes.
• Logic Interaction Condition: No discharge notification from BCM (Body Control Module) received, and after service diagnostic DTC needs stable monitoring cycle of $3s$. This ensures normal diagnostic flow is not interfered with when vehicle is in sleep or specific service mode.