What Should a Truck Driver Do After a Highway Shoulder Breakdown?

When a commercial truck loses power and stops on a highway shoulder, check whether it blocks a traffic lane and whether anyone is injured or there is fire, fuel or hazardous material leakage, or a secondary-crash risk. California Highway Patrol guidance says to call 911 when a vehicle is disabled in a traffic lane or another dangerous location. Elsewhere in a metropolitan area, call 511 and say “Roadside Assistance,” or contact the carrier and a qualified heavy-duty towing provider.

Under 49 CFR 392.22, a stopped commercial motor vehicle must activate hazard warning flashers immediately and place required warning devices as soon as possible, within 10 minutes. On a two-way road, use approximately 10 feet on the traffic side and 100 feet in each direction. On a divided or one-way highway, place all three toward approaching traffic at approximately 10, 100, and 200 feet. If the truck is within 500 feet of a curve, hillcrest, or sight obstruction, the far device may need to be 100 to 500 feet away. Do not enter uncontrolled traffic when placement cannot be performed safely.

Record breakdown time accurately. Inspecting or repairing the truck, obtaining assistance, and remaining with a disabled CMV are generally on-duty activities under 49 CFR 395.2. Off Duty or Sleeper Berth may apply only when the driver is fully relieved and able to rest. Driving to a maintenance facility advances the carrier’s business and is not Personal Conveyance. ELD edits require annotations, and automatically recorded driving time cannot be erased or shortened.

Separate a routine breakdown from an unsafe condition under 49 CFR 396.7 and a formal out-of-service order. An unsafe truck may move only to the nearest safe repair location when that is less hazardous than leaving it on the highway. A formally out-of-service vehicle must follow the inspection report and enforcement instructions. Under section 396.9, ordinary towing counts as operation, subject to a limited crane-or-hoist provision.

Preserve ELD annotations, dispatch messages, photographs, inspection reports, towing invoices, repair work orders, and release-to-service records. These documents establish the timeline, but not every receipt is a required carry-on document.