Remove the sunlight sensor from the dashboard, then disconnect the 2P connector. Be careful not to damage the sensor and the dashboard. Install the sensor in the reverse order of removal.

Turn the ignition switch ON (II). Measure the voltage between the terminals with the (+) probe on the No. 1 terminal and the (-) probe on the No. 2 terminal with the 2P connector connected. The voltage will not change under the light of a flashlight or a fluorescent lamp. Voltage should be: 3.6 - 3.7 V or more with the sensor out of direct sunlight. 3.6 - 3.5 V or less with the sensor in direct sunlight.