Final answer:
The white wire of a 4-way flat connector is typically connected to the ground wire of the trailer harness. Local wiring color codes should be confirmed to ensure proper and safe connections.
Step-by-step explanation:
The student asked to connect the white wire of the 4-way flat connector to the appropriate wire of the trailer harness. In the context of the provided information regarding wire color codes, the white wire in a trailer harness typically represents the neutral or ground wire. It is important to note that color codes may vary depending on the region. Therefore, while in many regions the white wire is used for the ground connection, one should always confirm the local color codes to ensure proper and safe wiring practices. However, for a standard 4-way flat trailer connector in North America, the white wire is commonly recognized as the ground wire. Therefore, the white wire of the 4-way flat connector should be connected to the ground wire of the trailer harness, which may also be white, green, yellow, or a bare wire.