What it means
A receiving module detected implausible data from the front-right distance range sensor (corner radar). Distance/azimuth values fail plausibility checks and are rejected by ADAS functions.
At a glance
- Usually lights the warning light of the system that lost communication
How it works
The front-right corner radar sends distance and angle information over the vehicle network for cruise control and other driver-assistance features. U043C is set when a receiving module judges that right-side radar data implausible and rejects it; it does not necessarily mean the radar is offline.
Common causes
Most likely first.
- Module internal fault or sensor input drift
- Software version mismatch after replacement
- Gateway module routing CAN messages incorrectly
Symptoms
- Multiple warning lights may illuminate
- Affected modules may go into limp mode or shut down
- Specific functions inoperative depending on module
- Diagnostic tools may show communication faults
How to diagnose it
- Scan all modules and save freeze-frame data and communication codes to identify which module rejected the front-right radar data and under what conditions.
- Compare the front-right radar's live distance and angle readings with the front-left radar and the surrounding scene.
- Inspect the front-right radar mounting, cover, connector, and harness for damage, dirt, obstruction, or misalignment.
- Look for related network or gateway codes and check the radar's wiring and connectors for corrosion, looseness, or damage.
- If a radar or module was recently replaced, verify software compatibility and calibration, then test the right radar and receiving module using the vehicle's service procedure.
Common fixes
- Clean the front-right radar cover and clear any obstruction.
- Repair a loose or damaged front-right radar connector or wiring.
- Correct the right radar's mounting or calibration if it is out of position.
- Update or configure replacement radar, gateway, or receiving-module software to the vehicle's requirements.
- Replace the front-right radar or repair the receiving module only after diagnosis identifies it as faulty.
Can I keep driving?
If only driver-assistance warnings are present, drive manually and do not rely on adaptive cruise or affected assistance features. Stop safely and arrange help if warnings indicate a problem with braking, steering, or vehicle control.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.