The Federal Aviation Administration said on Friday that it would order inspections of the wiring in emergency transmitters on Boeing 787s as it continues to narrow the search for what caused a fire on one of the jets last week at London’s Heathrow Airport.

Safety investigators are examining whether a pinched wire on a harness connecting a battery to the transmitter caused or helped spread the fire. They also want to check the transmitters’ battery for signs of unusual heating or moisture.

While the agency prepares the order over the next few days, Boeing plans to instruct all 13 airlines that use the Dreamliner to either inspect or remove the transmitters, which send out a plane’s location after a crash.

The F.A.A.’s plans to order only an inspection fall short of a recommendation on Thursday by British investigators, who called on the F.A.A. to order airlines to disable the batteries. It also might place the F.A.A. in conflict with other regulators. Air Transport World, a trade publication, on Friday quoted a spokesman for the European Aviation Safety Agency as saying that it was drafting instructions to European airlines to remove the transmitters.