United Airlines has become the third Boeing 787 operator to report finding a pinched wire in a fixed emergency locator transmitter (ELT).
The Star Alliance carrier shipped the defective component to Honeywell for evaluation, and replaced it with a new unit in the crown area of the 787's aft fuselage.
The US Federal Aviation Administration (FAA) mandated that United perform the inspection based on the recommendation of the UK Air Accidents Investigation Branch (AAIB).
The AAIB discovered a pinched wire between the ELT and its power source - a lithium-manganese-dioxide battery - while investigating a fire that damaged an Ethiopian 787 parked at London Heathrow airport on 12 July.
The AAIB is still investigating whether the pinched wire could have triggered the fire, but noted that the ELT is the only system with a power source in the area of the fire damage.
Earlier today, All Nippon Airways also reported finding a pinched wire in one of the fixed ELTs installed in one of the carrier's 787s.
Honeywell has delivered more than 6,000 Rescu406 ELTs since it was certificated by the FAA about a decade ago, and says the component has never before been linked to a fire incident.