On-Vehicle Inspection

1. Disconnect the A31 sensor connector.
2. Measure the voltage and resistance of the wire harness side connector.

   HINT:

   • Ignition switch ON
   • Light control switch AUTO
   • Vehicle's surroundings are bright

   Standard voltage 

   VOLTAGE CONDITION
   
   

   Tester Connection	Condition	Specified Condition
   A31-3 - Body ground	Ignition switch ON	5.2 to 9.0 V
   	Close driver's door again while ignition switch OFF	Below 1 V

   OK 

   CONTINUITY CONDITION
   
   

   Tester Connection	Specified Condition
   A31-6 - Body ground	Continuity

   If the result is not as specified, repair or replace the wire harness or connector.

3. Reconnect the A31 sensor connector.
4. Measure the voltage of the connector.
   • Ignition switch ON
   • Light control switch AUTO
   • Vehicle's surroundings are bright

Standard voltage 

If the result is not as specified, repair or replace the wire harness or connector.

Fig 1: Identifying Connector Terminals Automatic Light Control Sensor

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