What inspection should be accomplished after a wire harness is installed?

• A. Inspect for sufficient slack between the last clamp and the electronic equipment to prevent strain of the terminals
• B. Inspect the harness for proper routing and slack
• C. Inspect the color coding of wires
• D. Inspect only at the connectors

Answer: (A)

The main idea here is to prevent strain on electrical terminations by ensuring there is enough slack in the harness after it’s installed. If the harness is pulled tight up to the last clamp or device, vibration, movement of the aircraft, or thermal expansion can transfer tension directly to the terminal crimps or solder joints. Over time this stress can cause fatigue, cracking, or intermittent connections.

Providing sufficient slack between the last clamp and the electronic equipment allows the harness to move independently from the equipment and clamps, absorbing vibration and movement without loading the terminations. It also leaves room for thermal expansion and engine/airframe movement, which helps maintain a reliable connection and reduces the chance of loosening or damage.

Color coding matters for identification, but it doesn’t address the mechanical strain issue. And inspecting only at the connectors ignores potential pulling forces along the length of the harness or at intermediate clamps. Proper routing and some slack throughout the harness are important, but the critical inspection after installation is confirming there is enough slack specifically to prevent terminal strain.