A key that defeated an interlock switch is at the heart of a wrongful death lawsuit over the April 7, 2025, killing of a longtime Michigan factory mechanic, whose body was found pinned between a robotic arm and a conveyor at a Stellantis engine plant.
Ronald Adams, 63, suffered catastrophic injuries at the Dundee Engine Plant, the automaker’s facility that builds engines for Jeep, Chrysler, Dodge and Ram vehicles. Court records lay out how the veteran mechanic — a U.S. Air Force veteran who had also put in time at Northwest Airlines — came to be caught by machinery he had spent 20 years working around.
Left Alone at the Machine
Adams was part of a crew retooling the plant for production of a new four-cylinder engine. His assignment that day was repairing a large industrial chamber washer, equipment used to clean engine components, while a robotic arm shuttled parts in and out of it. Two of the coworkers assigned to the job stepped away on a break, leaving him by himself with the machinery, the complaint states.
When one of them came back, Adams was trapped. A worker’s statement described him as “hunched over,” his right arm resting on the conveyor and the robotic arm bearing down on his right shoulder.
Paramedics and an on-site electrician were called in, and the arm was lifted off him. Three workers helped emergency crews shift the grandfather from the conveyor belt to a stretcher. He was rushed to a hospital and died there. The medical examiner attributed the death to catastrophic crushing injuries and “traumatic asphyxia.”
A Bypassed Safety Mechanism
The wrongful death action, brought by Shamenia Stewart-Adams and filed in Wayne County Circuit Court, argues that the robot should never have been able to move at all while her husband was inside its reach. The protective mechanism built into the washer for anyone servicing it had been “electronically bypassed,” the filing says. With a key defeating the interlock, the arm was free to operate at full production speed instead of the slow manual mode required when someone is working within range.
That override, the estate contends, is what let the arm swing into motion, pinning and crushing Adams. Nothing indicates he turned the key himself, according to the suit, which also faults the plant for inadequate machine guarding and unsafe work practices at the time of the death. The estate wants the company held responsible, arguing the proper protections simply weren’t in place during what was meant to be a routine repair.
The Michigan Occupational Safety and Health Administration (MIOSHA), the state’s workplace safety agency, launched a fatality investigation the same day Adams died. More than a year on, that file was still open, with no citation or penalty issued.
Adams is one of three Stellantis employees to die on the job over a two-year stretch. Antonio Gaston, 53, was snagged on a conveyor and crushed by equipment at the Toledo Assembly Complex on August 21, 2024. James Brasher, 57, plunged from a loading dock on the second floor of the automaker’s Center Line facility on August 1, 2026, and his head hit a dumpster about 25 feet down. Regulators cited the company with a serious violation and a roughly $16,000 fine over Gaston’s death; Stellantis fought it and settled for about $11,000. Brasher’s death remains under state investigation.
The automaker has stayed silent on the specific claims in the lawsuit. Speaking generally about its safety record, the company said it “regularly evaluate[s] and strengthen[s] our internal standards and protocols to protect employees across our operations,” and that sharing best practices “helps reinforce our safety culture and supports consistent performance.” United Auto Workers Vice President Rich Boyer said the fatalities “shouldn’t happen” and called for tougher health and safety procedures.