Code result
U0406
Invalid Data Received from Cruise Control Front Distance Range Sensor
Moderate severity
What it means
ACC receives bus messages from the radar but their content is implausible (e.g. negative distances, jittering targets). Adaptive cruise is disabled until the radar reports plausible data again.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Radar obstructed by snow/dirt
highOne of the most commonly reported causes for this code — check this first.
Radar misaligned after collision
mediumA plausible cause — test and verify before replacing parts.
Gateway module routing CAN messages incorrectly
lowLess common, but worth ruling out after the more likely causes.
Related help
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