Light Control Rheostat: Tercel

Remove light control rheostat. Light control rheostat is located on left side of instrument panel. Turn rheostat knob to OFF position (fully counterclockwise). Check for continuity between rheostat terminals. If continuity does not exist, go to next step. If continuity exists, replace rheostat.
Measure resistance between rheostat terminals while slowly rotating rheostat knob from dark side to bright side. See Fig 3. Resistance should change from about 10 ohms to infinite as knob is rotated.

Fig 1: Testing Light Control Rheostat (Avalon Shown; Camry, Celica & Supra Are Similar)

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Fig 2: Testing Light Control Rheostat (Corolla)

Fig 3: Testing Light Control Rheostat (Tercel)