What Should a Truck Driver Do After a Highway Shoulder Breakdown?
If a truck loses power on a freeway and remains controllable, try to get onto the shoulder. Once stopped, check whether the whole vehicle is clear of the travel lane, whether you can get out safely, and whether anyone is injured or there is fire, fuel or hazardous material leaking. If the vehicle blocks a lane, approaching drivers cannot readily see it or another collision is an immediate risk, call 911 as directed in the California Highway Patrol freeway breakdown guidance. From a relatively safe stopping position, contact dispatch, fleet safety or a provider equipped for heavy-truck recovery. In metropolitan areas, you may also call 511 and say “Roadside Assistance” to request help finding suitable service.
Activate hazard flashers immediately
Under 49 CFR § 392.22, a commercial motor vehicle stopped on the traveled portion or shoulder of a highway for a breakdown or another reason other than a necessary traffic stop must have its hazard flashers activated immediately. Keep them flashing until the required warning devices are in place. Use the flashers again when retrieving the devices and preparing to move. They may remain on after triangles are placed but do not replace the triangles.
Position the triangles for the roadway and available sight distance
Consider the common case of a truck facing the direction of travel on the right shoulder. Place the triangles along that shoulder ahead of and behind the truck, not across the adjacent live lane. A set of reflective triangles has three devices. Measure the distances from the stopped vehicle.
On a typical two-way road, put two behind the truck and one in front. Put one about 10 feet behind the rear to mark the vehicle and the second about 100 feet behind to warn traffic approaching from the same direction. Put the third about 100 feet in front to warn oncoming traffic.
On a one-way or divided highway, put all three behind the truck, approximately 10, 100 and 200 feet away. Traffic on that side travels in one direction, so there is no additional triangle in front.
Where a curve, hillcrest or other obstruction limits the view, move the farthest triangle on the obstructed approach to a point 100 to 500 feet from the vehicle that gives adequate warning. Place required devices as soon as possible and no later than 10 minutes after stopping.
Assess whether you can get out safely. If traffic is too close, the shoulder too narrow or placement would require entering traffic you cannot control, call 911 and follow on-scene directions. 49 CFR § 393.95 lists three bidirectional reflective triangles meeting FMVSS No. 125 as one compliant option. For fusees or other flame-producing devices, check restrictions for the vehicle and cargo. Vehicles specified in the rule carrying explosives, flammable gas or flammable liquid, and vehicles using compressed gas as motor fuel, must not carry flame-producing warning devices. Where fuel or flammable gas is leaking, do not use flame signals where they could cause fire or explosion.
Log what you actually do while awaiting help
Under 49 CFR § 395.2, inspecting or repairing the vehicle, obtaining assistance or attending a disabled commercial vehicle counts as on-duty time. When checking a fault, helping with a repair or waiting with the truck for a tow, the usual entry is On Duty, Not Driving. Consider Off Duty or Sleeper Berth only if the carrier has fully relieved the driver of duty and the driver can actually rest under the applicable conditions.
ELD entries must reflect actual activity. Under 49 CFR § 395.30, explain edits or additions and have the driver review and confirm them. Automatically recorded driving cannot be deleted or shortened to save hours. Moving to a repair location serves the carrier’s business and cannot be logged as personal conveyance. If an officer orders movement for site safety, record the actual movement and direction and explain the circumstances in the ELD.
Moving off the shoulder depends on the defect and any enforcement order
For an ordinary breakdown, assess the component, on-site inspection and technician’s opinion. 49 CFR § 396.7 prohibits operating a vehicle in a condition likely to cause an accident or a breakdown. A defect discovered on the highway may permit limited movement only to the nearest location where repairs can safely be made and only if moving poses less risk to the public than leaving the vehicle on the highway. Stop at that repair location. Do not carry on with the original delivery.
A formal out-of-service notice is more restrictive. Under 49 CFR § 396.9, the vehicle cannot be operated until the required repairs are completed. Operation includes ordinary towing. The rule provides limited arrangements for removal by crane or hoist. Follow the inspection report and enforcement directions to arrange the appropriate heavy-duty tow. Do not treat an out-of-service vehicle as an ordinary breakdown.
Preserve the repair and inspection records
Under 49 CFR § 396.11, a driver identifying a defect affecting safety or likely to cause mechanical failure should describe it on the driver vehicle inspection report (DVIR) and sign. Before returning the vehicle to service, the carrier must repair safety-related defects or certify on the report when repair is unnecessary. For California intrastate operations, California Vehicle Code § 34500.7 requires handling DVIRs under state requirements. Check those as well as the federal provision.
If a roadside inspection also occurred, deliver the Driver Vehicle Examination Report to the carrier on reaching the next terminal or facility. If you will not reach one within 24 hours, transmit the report immediately. The carrier usually must certify correction within 15 days after inspection, return the report as the issuing agency requires and retain a copy for 12 months.
Retain the towing invoice, roadside service ticket, repair order and invoice, parts and labor detail, completion time and confirmation of return to service. Carrier maintenance records must identify what was inspected or repaired and when and be retained under 49 CFR § 396.3. The items listed are not all federally required in every driver’s cab. The fleet should retain the originals together so it can reconstruct the work from more than scattered photos and messages.
Disclaimer. This article draws on Title 49 of the Code of Federal Regulations, FMCSA, CHP and the California Vehicle Code as accessible on August 25, 2026. It provides general information on freeway breakdown safety, warning devices, hours, towing and maintenance records. It does not determine a specific defect, site risk, out-of-service criterion, ELD status, towing method, repair adequacy, insurance liability or legal outcome. Location, traffic, weather, cargo, hazardous materials, defects and enforcement directions vary. Act on site safety, current regulations, the inspection report, officers’ instructions and the judgment of qualified maintenance and carrier safety personnel. There is no guarantee that 511, roadside assistance or an ordinary tow can handle every heavy vehicle, load or hazardous materials vehicle, or of any repair, return to service, inspection, coverage or payment outcome. Call 911 promptly for injury, fire, leakage, a vehicle obstructing a lane or other immediate danger. The author and publisher accept no liability for losses arising from actions taken on the basis of this article.
Electronic Code of Federal Regulations. “49 CFR § 392.22: Emergency Signals; Stopped Commercial Motor Vehicles.” eCFR, National Archives and Records Administration, https://www.ecfr.gov/current/title-49/subtitle-B/chapter-III/subchapter-B/part-392/subpart-C/section-392.22. Accessed 25 Aug. 2026.
Electronic Code of Federal Regulations. “49 CFR § 393.95: Emergency Equipment on All Power Units.” eCFR, National Archives and Records Administration, https://www.ecfr.gov/current/title-49/subtitle-B/chapter-III/subchapter-B/part-393/subpart-H/section-393.95. Accessed 25 Aug. 2026.
Electronic Code of Federal Regulations. “49 CFR § 395.2: Definitions.” eCFR, National Archives and Records Administration, https://www.ecfr.gov/current/title-49/subtitle-B/chapter-III/subchapter-B/part-395/subpart-A/section-395.2. Accessed 25 Aug. 2026.
Electronic Code of Federal Regulations. “49 CFR § 395.30: ELD Record Submissions, Edits, Annotations, and Data Retention.” eCFR, National Archives and Records Administration, https://www.ecfr.gov/current/title-49/subtitle-B/chapter-III/subchapter-B/part-395/subpart-B/section-395.30. Accessed 25 Aug. 2026.
Federal Motor Carrier Safety Administration. “Editing and Annotations.” ELD Frequently Asked Questions, U.S. Department of Transportation, https://eld.fmcsa.dot.gov/FAQ/Topics?name=Editing_and_Annotations. Accessed 25 Aug. 2026.
Federal Motor Carrier Safety Administration. “Personal Conveyance.” U.S. Department of Transportation, https://www.fmcsa.dot.gov/regulations/hours-service/personal-conveyance. Accessed 25 Aug. 2026.
Electronic Code of Federal Regulations. “49 CFR § 396.3: Inspection, Repair, and Maintenance.” eCFR, National Archives and Records Administration, https://www.ecfr.gov/current/title-49/subtitle-B/chapter-III/subchapter-B/part-396/subpart-A/section-396.3. Accessed 25 Aug. 2026.
Electronic Code of Federal Regulations. “49 CFR § 396.7: Unsafe Operations Forbidden.” eCFR, National Archives and Records Administration, https://www.ecfr.gov/current/title-49/subtitle-B/chapter-III/subchapter-B/part-396/subpart-A/section-396.7. Accessed 25 Aug. 2026.
Electronic Code of Federal Regulations. “49 CFR § 396.9: Inspection of Motor Vehicles and Intermodal Equipment in Operation.” eCFR, National Archives and Records Administration, https://www.ecfr.gov/current/title-49/subtitle-B/chapter-III/subchapter-B/part-396/subpart-A/section-396.9. Accessed 25 Aug. 2026.
Electronic Code of Federal Regulations. “49 CFR § 396.11: Driver Vehicle Inspection Report(s).” eCFR, National Archives and Records Administration, https://www.ecfr.gov/current/title-49/subtitle-B/chapter-III/subchapter-B/part-396/subpart-A/section-396.11. Accessed 25 Aug. 2026.
California Legislature. “California Vehicle Code § 34500.7.” California Legislative Information, https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=VEH§ionNum=34500.7. Accessed 25 Aug. 2026.
California Highway Patrol. “Frequently Asked Questions: Freeway Breakdown Assistance.” State of California, https://www.chp.ca.gov/faq/. Accessed 25 Aug. 2026.