Ford Motor Company announced a recall of 4,380,609 vehicles due to an issue with the integrated trailer module that could cause the trailer brakes to stop functioning in certain vehicles.

According to a safety recall notice on Feb. 20 by the National Highway Traffic Safety Administration, the integrated trailer module in vehicles in the recall population can stop communicating, usually when the vehicle is started.

If a trailer happens to be connected, drivers will notice that the trailer brake lights and turn signal indicators fail to illuminate—evidenced by a rapidly flashing turn signal indicator on the automobile’s instrument display.

Drivers will see a message on the instrument panel cluster stating “trailer brake module fault,” and may also see an additional dashboard message stating “blind spot assist system fault.” In vehicles that are equipped with high-series trailer modules, the trailer brakes will fail to engage while driving.

“These conditions result in a noncompliance with federal safety standards and can reduce a driver’s ability to control an attached trailer while making it less visible to other drivers, increasing the risk of a crash,” Ford said in a Feb. 26 post on its website.

The Dearborn, Michigan-based automaker said the safety recall affects almost 2.3 million F-150 trucks of model years 2012–2026. More than 1.13 million Ford F-250 SD trucks, nearly 130,000 Ford Ranger mid-size trucks, and 412,105 Maverick compact trucks of model years 2022–2026 are also involved in the recall. Additionally, 317,604 Expedition sport utility vehicles, 13,115 E-Transit cargo vans, and 75,029 Lincoln Navigator SUVs were included in the recall.

The integrated trailer control modules were manufactured by Horizon Global at its Reynosa, Mexico, facility. Ford first became aware of problems with the trailer module software in October 2025. The software error can occur even when a trailer isn’t connected, Ford noted.

Ford originally identified 57 warranty claims regarding the trailer module communications issue, but by early February, the company said a total of 405 warranty claims had been filed that could potentially be related to the integrated trailer control module software flaw.

To fix the issue, Ford will release an over-the-air software update for most affected vehicles beginning on March 17. The patch, which removes the communication vulnerability in the integrated trailer module, should be available for the entire recall population by May, Ford noted. Ford and Lincoln owners can also take their vehicles to a dealership to complete the update if they wish.

Ford said it will mail recall letters to affected owners starting on March 23. Ford and Lincoln owners can input their vehicle identification numbers into the NHTSA’s recall portal beginning March 17. Alternatively, they can contact Ford customer service at 866-436-7332 and reference recall number 26C10.