What it means
A receiving module detected implausible data from side obstacle detection module D (corner radar). Distance/closing-speed values fail plausibility checks and are rejected; blind-spot warning may be inhibited.
How it works
Side obstacle detection control module D, a corner radar, reports detected-object distance and closing-speed information over the vehicle network. Receiving modules check these values for plausibility; U0550 sets when a module rejects data attributed to radar D, potentially inhibiting the blind-spot function it serves.
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 record U0550, related driver-assistance codes, and freeze-frame details to determine which module rejected radar D's data and under what conditions.
- Use live data to check radar D's communication status and whether its distance and closing-speed readings respond plausibly to objects near the corresponding corner.
- Inspect radar D's mounting area for obstruction, dirt, impact damage, or misalignment, and check its connector and wiring for damage or corrosion.
- Check for recent bumper or body repairs, radar replacement, or software changes, and verify the module configuration and alignment requirements using manufacturer information.
- If the radar installation and wiring are sound, perform the manufacturer's network checks for message integrity and gateway routing.
Common fixes
- Clean the radar D sensing area and remove any obstruction.
- Repair a loose, corroded, or damaged connector or wiring to radar D.
- Restore the radar's mounting and alignment according to the manufacturer's procedure.
- Correct an incompatible module configuration or software mismatch after replacement.
- Repair or replace radar D if implausible data persists with sound wiring, mounting, and configuration.
Can I keep driving?
The vehicle is generally drivable, but blind-spot alerts dependent on radar D may be unavailable or unreliable. Check mirrors and blind spots directly and avoid relying on that assistance function until fixed.
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.