WARNING: This page is about a different car, the 2000 Toyota Tacoma. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: 4WD Circuit, California W/O 2-4 Select Switch
Fig 2: 4WD Circuit, Except California W/O 2-4 Select Switch
Fig 3: 4WD Circuit, W/ 2-4 Select Switch
Fig 4: Rear Differential Lock Circuit, California
Fig 5: Rear Differential Lock Circuit, Except California