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Violation code392.71

§392.71

Radar detector use or possession

49 CFR §392.71

At a glance

Severity
2
OOS eligible
No
BASIC category
Unsafe Driving
Typical fine
$100–$1,000 per offense

Drivers may not use a radar detector in a CMV, and the carrier may not require or permit one. Severity weight 2 in the Unsafe Driving BASIC, but a reliable indicator of broader speed-management problems.

§392.71 prohibits a CMV driver from using a radar detector and prohibits the carrier from requiring or permitting one in a CMV. The rule covers both active and passive radar/laser-detection devices. Mere possession in the driving compartment is sufficient — the device does not need to be plugged in.

Severity weight

Severity weight 2 in the Unsafe Driving BASIC. The weight is low, but a §392.71 finding is correlated with other speed-related citations and is a reliable indicator that the carrier's speed-management program needs work.

How to prevent it

  • Issue a written no-radar-detector policy and retain the acknowledgment in §391.51.
  • Spot-check vehicles during yard inspections — devices migrate from personal vehicles to CMVs without the carrier knowing.
  • Address the underlying incentive: drivers carry detectors when dispatch schedules don't fit posted speed limits.

How Roadworthy HQ helps

§392.71 findings link to the driver record and to the §385.337(b) corrective-action documentation. The policy and acknowledgment retain in the audit binder under §391.51.

Related violations

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Roadside findings link to the driver and vehicle, with corrective action documented and surfaced in the audit binder.

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Not legal advice · CFR is the authoritative source · SMS Appendix A publishes current severity weights