Violation code

393.70B1IICDCSBL

Coupling - Countersunk screw coupler has any loose or broken bolt

Not in SMSOOS· FMCSA A&I All Violations

393.70B1IICDCSBL is a Vehicle violation under 49 CFR §393.70B1IICDCSBL. It is an out-of-service violation; it is not scored in the SMS. Nationally it was cited 5 times in the last five years, with an OOS rate of 100.0%.

📊

National roadside inspection stats

as of 9/20/2026

Inspections

that found this code

Violations

total written

OOS rate

100.0%

5 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.

📎

Not used in SMS BASIC scoring

Recorded on your inspection report and visible on the PSP, but contributes 0 points to CSA BASIC scores — even if cited Out-of-Service.

Violation group: Vehicle
Regulation §: 393.70B1IICDCSBL
Severity weight: N/A
Used in SMS: No
Status: Active
Updated: 9/20/2026

Last updated September 2026

⚡

Think this violation was written incorrectly?

Generate a polished DataQs challenge letter for 393.70B1IICDCSBL in about 5 seconds. AI quotes the CFR, predicts your grant chance.

⚡ Draft a challenge →

What 393.70B1IICDCSBL means — and how to avoid it

In plain English

In plain terms, 393.70B1IICDCSBL is cited for coupling - Countersunk screw coupler has any loose or broken bolt. It falls under the FMCSA rules on parts and accessories needed for safe operation. Because it’s an out-of-service condition, an inspector can put the driver or vehicle out of service on the spot until it’s corrected.

What the inspector checks

•Fifth-wheel mounting, locking jaws, and secure kingpin engagement
•Cracks or excessive movement in the coupling
•Safety devices/chains where required

How to prevent it

✓Do a tug test and visually confirm the jaws are locked on the kingpin
✓Grease and inspect the fifth wheel on schedule
✓Never move with an unconfirmed coupling

How it affects your CSA

0 CSA points

393.70B1IICDCSBL is not scored in the SMS. It adds 0 CSA points — even if written out-of-service — but it still appears on the inspection report and the driver’s PSP.

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

📚

Challenging 393.70B1IICDCSBL through FMCSA DataQs

If this violation was written incorrectly, here are the angles trucking-safety managers use to contest it. Playbook: Codes not used in SMS scoring.

Common ways to challenge this code

Not used in SMS — should not affect BASIC
This code is on the inspection report but is excluded from SMS BASIC scoring per Appendix A. Use DataQs to correct the underlying data quality issue if the code was written in error, but understand it does not affect the CSA percentile.
Evidence that wins
- ✓FMCSA SMS Methodology Appendix A reference
- ✓Underlying inspection report

Common pitfalls — avoid these

⚠These codes still appear on PSP — challenge the data if the cite was wrong

⚡ Draft a challenge for 393.70B1IICDCSBL →Read the DataQs guide first

Other Vehicle codes

Codes under the same FMCSA violation group

❓

Frequently asked questions about 393.70B1IICDCSBL

What does violation 393.70B1IICDCSBL mean?

393.70B1IICDCSBL is the FMCSA roadside-inspection violation code for "Coupling - Countersunk screw coupler has any loose or broken bolt", part of the Vehicle group, cited under 49 CFR §393.70B1IICDCSBL.

What BASIC does 393.70B1IICDCSBL affect?

393.70B1IICDCSBL is not scored in any CSA BASIC. It is recorded on the inspection report and appears on the PSP, but it contributes 0 points to a carrier's SMS BASIC percentiles.

Is 393.70B1IICDCSBL an out-of-service (OOS) violation?

Yes. 393.70B1IICDCSBL is an out-of-service violation, meaning the driver or vehicle can be placed out of service at the roadside until the issue is corrected. OOS violations also add an extra severity point in SMS scoring.

How many CSA points does 393.70B1IICDCSBL add?

393.70B1IICDCSBL adds 0 CSA points because it is not used in SMS scoring, even when written out of service.

How can a driver prevent 393.70B1IICDCSBL?

Do a tug test and visually confirm the jaws are locked on the kingpin; Grease and inspect the fifth wheel on schedule; Never move with an unconfirmed coupling.

Can 393.70B1IICDCSBL be challenged through DataQs?

Yes. If you believe 393.70B1IICDCSBL 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 393.70B1IICDCSBL Carrier CSA lookup CSA glossary

Turn this violation into a training moment

Assign training on this exact topic — and prove it

Looking up a code is step one. FleetTrained — built by the same safety manager behind VioCodes — lets you assign a video on this topic; drivers quiz and sign in their language, and you get a DOT-ready certificate so it stops happening.