This is a list of restriction codes that may be added to a South Carolina commercial driver's license (CDL) or commercial learner's permit (CLP). A description for each code is provided along with an explanation of why a restriction code may be added to a CDL or CLP and what can be done to have it removed.

Code E - No Manual Transmission Equipped CMV

You cannot operate any commercial motor vehicle (CMV) that has a manual transmission if the vehicle you used during the skills test had automatic or semi-automatic transmission.

For the SCDMV to remove this restriction, you must do both of the following:

• Hold a CLP without the restriction for 14 days
• Pass the on-road portion of the skills test in a CMV that does not have an automatic transmission

Code K - Intrastate Only

If you're 18 to 20, you must have this restriction which means you cannot operate any CMV outside of South Carolina. This restriction only allows intrastate transportation of shipments/loads that start and end in this state. The load cannot start or finish outside the state of SC (interstate shipment).

For the SCDMV to remove this restriction, you must visit an SCDMV office once you turn 21 years old to upgrade your license.

Code L - No Airbrake Equipped CMV

You cannot operate a CMV that has air brakes if the vehicle used during the road test was not equipped with air brakes.

For the SCDMV to remove this restriction, you must do all the following:

• Hold a CLP without the restriction for 14 days.
• Pass the knowledge test for air brakes if you have not done so already.
• Pass the vehicle inspection and the on-road portion of the skills test in a CMV that has air brakes.

Code M - No Class A Bus Passenger Vehicle

You cannot operate any class A passenger vehicle if you used a class B passenger vehicle during the skills test for your passenger endorsement.

For the SCDMV to remove this restriction, you must do both of the following:

• Hold a CLP without the restriction for 14 days.
• Pass the skills test in a class A passenger vehicle.

Code N - No Class A and B Bus passenger vehicle

You cannot operate any class A or B passenger vehicle if you used a class C passenger vehicle during the skills test for your passenger endorsement.

For the SCDMV to remove this restriction, you must do both of the following:

• Hold a CLP without the restriction for 14 days.
• Pass the skills test in a class A or class B passenger vehicle. If a class B passenger vehicle is used, the N restriction will be replaced with an M restriction.

Code O - No Tractor Trailer CMV

You cannot operate any CMV tractor (pulling unit) with a fifth-wheel connection if you used a unit with a pintle hook, or other non-fifth wheel connection (such as a gooseneck, or ball and chain hook up) during the skills test.

For the SCDMV to remove this restriction, you must do both of the following:

• Hold a CLP without the restriction for 14 days.
• Pass the complete skills test.

The unit used during the skills test must include a fifth-wheel connection.

Code P - No Passengers in CMV Bus

You cannot operate any CMV bus in any class (A, B, or C) that is carrying passengers. The only passengers allowed in a vehicle operated by a CLP holder with a P restriction are federal or state auditors and inspectors, test examiners/testers, other trainees, or the CDL supervising driver.

For the SCDMV to remove this restriction, you must do all the following:

• Hold a CLP without the restriction for 14 days.
• Pass any necessary knowledge tests for the vehicle you are operating.
• Pass the complete skills test for that class vehicle.

Code P1 - Excepted Interstate

You cannot operate any CMV outside of the authorized activities defined by Federal Motor Carrier Safety Administration, and you are not required to meet the USDOT medical certificate requirements.

For the SCDMV to remove this restriction, you must do both of the following:

• Present a DOT medical certificate.
• Complete the CDL Holders Medical Certification Requirements (SCDMV Form DL-405A). Select a type of commerce operation other than "Excepted Interstate."

Code V - Medical Variance

You have a medical variance (federal waiver or skills performance evaluation) that goes along with your DOT medical certification. The SCDMV will never remove this restriction as long as the DOT medical certificate references a medical variance.

Code X - No Cargo in CMV Tank Vehicle

You cannot operate any CMV tank vehicle with any residue in the tank. If the tank vehicle previously contained hazardous materials, the tank must be purged, and the operator must carry a purge certificate.

For the SCDMV to remove this restriction from a CLP you must do all the following:

• Hold a CLP without the restriction for 14 days.
• Pass any necessary knowledge tests for the vehicle you are operating.
• Pass the complete skills test for that class and type of vehicle.

Code Z - No Full Air Brake Equipped CMV

You cannot operate any CMV with full air brakes if you performed the skills test in a vehicle equipped with air over hydraulic brakes. Air over hydraulic brakes includes any braking system operating partially on the air brake and partially on the hydraulic brake principle.

For the SCDMV to remove this restriction, you must do all of the following:

• Hold a CLP without the restriction for 14 days.
• Pass any necessary knowledge tests for the vehicle you are operating.
• Pass the vehicle inspection and on-road portion of the skills test. The unit used during the skills test must have full air brakes.