A device for verifying wiring connections during the assembly of a wire harness. The wire harness comprises a connector having an array of terminals and a plurality wires connected to individual ones of the terminals. The device comprises a transmitter for applying different signals to different terminals for emitting a corresponding electromagnetic signal from a wire connected to that terminal. Each electromagnetic signal has an associated identifying characteristic. A detector is used to receive the electromagnetic signals emitted from the wires connected to terminals, and a processor generates an output which is used to identify the received electromagnetic signals based on their detected identifying characteristics. A method of assembling a wire harness using the device is also disclosed.