Wiring Harness Testing
WARNING: This page does not describe the selected car, but rather 17 other vehicles, including the 2003 Toyota Tundra, 2003 Toyota Tacoma, 2003 Toyota Sienna, 2003 Toyota Sequoia, and 2003 Toyota RAV4. However, it is still accessible from the selected car via links, so may be relevant.
Using DVOM, monitor suspected circuit or component. Lightly shake wiring harness while noting fluctuation in DVOM reading. Inspect wiring harness at area where it goes through the body for signs of damage.