Step 1 - Inspect Front Personal Light Switch Continuity

WARNING: This page is about a different car, the 2002 Toyota Tundra. However, it is still accessible from the selected car via links, so may be relevant.

Disconnect the connector from the personal light.
Push the personal light switch ON, check that continuity exists between terminal 3 and body terminal 1.

Fig 1: Testing Front The Personal Light (1 Of 2)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Turn the light switch to DOOR, check that continuity exists between terminal 2 and 3.

Fig 2: Testing Front The Personal Light (2 Of 2)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

If operation is as specified, replace the switch.