On-Vehicle Inspection

CHECK AUTOMATIC LIGHT CONTROL SENSOR

Disconnect the L1 sensor connector.
Connect the voltmeter's positive (+) lead to terminal 6 and the negative (-) lead to terminal 3.

Measure the voltage of the connector.

Standard voltage

STANDARD VOLTAGE SPECIFICATION

Tester Connection	Condition	Specified Condition
L1-3 (CTLE) - L1-6 (CTLB)	Always	10 to 14 V

Fig 1: Identifying L1 Sensor Connector

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Measure the resistance of the connector.

Standard resistance

STANDARD RESISTANCE SPECIFICATION

Tester Connection	Condition	Specified Condition
L1-3 (CTLE) - Body ground	Always	Below 1 Ω

Check the waveform of the L1 sensor connector.

STANDARD VOLTAGE SPECIFICATION

Tester Connection	Condition	Specified Condition	Tester Range
L1-3 (CTLE) - L1- 5 (CTLS)	Engine switch on (IG), Headlight dimmer switch in AUTO	Correct waveform is as shown	5 V/DIV., 5 msec./DIV.

HINT:

If the ambient light becomes brighter, width A becomes narrower.

If the result is not as specified, replace the automatic light control sensor.

Fig 2: Waveform L1 Sensor Connector