What safety practices are essential when troubleshooting aircraft electrical systems to protect personnel and equipment?

What safety practices are essential when troubleshooting aircraft electrical systems to protect personnel and equipment?

• A. Work on live circuits to speed up testing.
• B. Bypass safety devices to test.
• C. Use uninsulated tools near power.
• D. De-energize circuits, lockout/tagout, use insulated tools, PPE, avoid contact with energized parts, and follow approved procedures.

Answer: (D)