Terminal C Inspection

WARNING: This page is about a different car, the 2004 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.

Measure the wave pattern of the terminal C on the panel light control switch using an oscilloscope.
Set the headlight switch to either the TNS or headlight position.
Set the panel light control switch to the brightest position.

Fig 1: Measuring Wave Pattern Of Terminal C On Panel Light Control Switch
Courtesy of MAZDA MOTORS CORP.
Verify that the pattern on the screen is as shown in the figure.

Fig 2: Wave Pattern Appears On Screen
Courtesy of MAZDA MOTORS CORP.
Verify that the pattern on the screen matches the pattern shown in the figure as the panel light control switch is gradually turned to the darkest position.

Fig 3: Matching Wave Patterns

Courtesy of MAZDA MOTORS CORP.