Violation code

383.91(a)

Operating a CMV with improper CDL group

Driver Fitness8Non-OOS· SMS Appendix A v3.20

383.91(a) is a License-related: High violation under 49 CFR §383.91(a). It falls in the Driver Fitness BASIC with a severity weight of 8/10. Nationally it was cited 6,288 times in the last five years, with an OOS rate of 97.7%.

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National roadside inspection stats

as of 10/20/2026

Inspections

6,267

that found this code

Violations

6,288

total written

OOS rate

97.7%

6,146 OOS

Source: FMCSA roadside inspection data (last 5 years). The OOS rate is the share of these violations that led the officer to mark the driver or vehicle out of service.

Violation group: License-related: High
Regulation §: 383.91(a)
Severity weight: 8
Used in SMS: Yes
Status: Active
Updated: 10/20/2026

Last updated October 2026

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Notes

DSMS: Y

What 383.91(a) means — and how to avoid it

In plain English

In plain terms, 383.91(a) is cited for operating a CMV with improper CDL group. It falls under the FMCSA rules on CDL standards and endorsements.

What the inspector checks

•Valid CDL of the right class with required endorsements
•Current medical examiner’s certificate
•Driver not disqualified and carrying required documents

How to prevent it

✓Track CDL, medical card, and endorsement expirations ahead of time
✓Keep the DQ file complete and the medical card on the driver
✓Renew before, not on, the expiration date

How it affects your CSA

up to 24 pts (fresh)

Severity 8/10. A fresh citation counts at the 3× time weight — up to 24 points toward the Driver Fitness BASIC — then tapers to 2× after 6 months and 1× after a year, dropping off the score at 24 months.

General guidance from the violation’s FMCSA classification — not legal advice, and not a substitute for the inspector’s findings or 49 CFR.

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Challenging 383.91(a) through FMCSA DataQs

If this violation was written incorrectly, here are the angles trucking-safety managers use to contest it. Playbook: Driver Fitness.

Common ways to challenge this code

Medical certificate was valid and on file
A valid medical examiner's certificate was in the driver's qualification file and was either not produced at roadside or not properly recognized.
Evidence that wins
- ✓Copy of the valid medical examiner's certificate
- ✓Driver qualification file index
- ✓National Registry verification printout
CDL class / endorsement was correct for the operation
The driver's CDL class and endorsements were correct for the vehicle and cargo being operated.
Evidence that wins
- ✓Copy of the valid CDL with endorsements
- ✓Vehicle registration showing GVWR/configuration
- ✓Bill of lading or shipping papers showing cargo

Common pitfalls — avoid these

⚠A medical certificate that expired the DAY of inspection still fails — there is no grace period

⚡ Draft a challenge for 383.91(a) →Read the DataQs guide first

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Codes under the same FMCSA violation group

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Frequently asked questions about 383.91(a)

What does violation 383.91(a) mean?

383.91(a) is the FMCSA roadside-inspection violation code for "Operating a CMV with improper CDL group", part of the License-related: High group, cited under 49 CFR §383.91(a).

What BASIC does 383.91(a) affect?

383.91(a) falls under the Driver Fitness BASIC in the FMCSA Safety Measurement System (SMS).

What is the CSA severity weight of 383.91(a)?

383.91(a) carries a severity weight of 8 out of 10. Higher weights indicate violations more closely tied to crash risk, and they count more toward a carrier's Driver Fitness score.

Is 383.91(a) an out-of-service (OOS) violation?

No. 383.91(a) is not an out-of-service violation, so on its own it does not trigger an out-of-service order at the roadside.

How many CSA points does 383.91(a) add to a carrier's score?

The point contribution of 383.91(a) depends on its severity weight (8/10) multiplied by a time weight of 3, 2, or 1 based on how recent the inspection is. You can calculate the exact contribution with the CSA points calculator.

How can a driver prevent 383.91(a)?

Track CDL, medical card, and endorsement expirations ahead of time; Keep the DQ file complete and the medical card on the driver; Renew before, not on, the expiration date.

Can 383.91(a) be challenged through DataQs?

Yes. If you believe 383.91(a) was recorded in error, you can file a Request for Data Review (RDR) through the FMCSA DataQs system with supporting evidence. A successful challenge can remove or correct the violation on your record.

Keep going

CSA points calculator How to challenge a violation Draft a DataQs letter for 383.91(a)Driver Fitness BASIC Carrier CSA lookup CSA glossary

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