1. Connect the connector to the panel light control switch.
2. Connect the negative battery cable.
3. Measure the voltage at the panel light control switch using voltmeter.
4. If the value are not as specified in the Terminal Voltage List (Reference), inspect the parts under Action and related wiring harnesses.
5. If the system does not work properly even though the parts or related wiring harnesses do not have any malfunction, replace the panel light control switch.
Terminal Voltage Table (Reference)


Terminal C inspection
1. Measure the wave pattern of the terminal C on the panel light control switch using an oscilloscope.

2. Set the headlight switch to either the TNS or headlight position.
3. Set the panel light control switch to the brightest position.
4. Verify that the pattern on the screen is as shown in the figure.

5. 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.

Panel light control switch removal/installation
Wiper and washerMazda 6 Service Manual: Air intake actuator inspection
1. Connect battery positive voltage to terminal D or F and ground to terminal
F or D of the air intake actuator.
2. Verify that the air intake actuator operates as shown below.
If not as specified, replace the air intake actuator.
...
Mazda 6 Service Manual: Illuminated Entry System
When the illuminated entry system operates, the overhead lights, the courtesy
lights, and an ambient light* turn on in the following conditions:
The driver's door is unlocked after the ignition is switched OFF.
The ignition is switched OFF with all doors closed.
NOTE
(Overhead lights) ...