Inspection Procedure

WARNING: This page is about a different car, the 2007 Lexus SC 430. However, it is still accessible from the selected car via links, so may be relevant.

CHECK OPERATION (AUTOMATIC LIGHT CONTROL SENSOR)
1. Connect the intelligent tester (with CAN VIM) to the DLC3.
2. Turn the ignition switch ON and intelligent tester main switch ON.
3. Check that the value of the illumination rate changes in the following range when the light sensor is put in the light or covered by a hand.
  OK: 0.008 to 0.022 seconds
  
  HINT:
  - This is the time taken for the light sensor to generate one cycle of frequency according to the brightness.
  - When not using intelligent tester, refer to the following procedures (see ON-VEHICLE INSPECTION ).
NG: REPLACE AUTOMATIC LIGHT CONTROL SENSOR

OK: Go to Next step

CHECK WIRE HARNESS (ECU - SENSOR)

Disconnect the D5 ECU connector.
Disconnect the A26 sensor connector.

Measure the resistance of the wire harness side connectors.

Fig 1: Identifying Driver Side Junction Block ECU And Automatic Light Control Sensor Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard resistance

RESISTANCE SPECIFICATION

Tester Connection	Specified Condition
D5-2 (CLTB) - A26-6 (CLTB)	Below 1 Ω
D5-13 (CLTS) - A26-5 (CLTS)	Below 1 Ω
D5-14 (CLTE) - A26-3 (CLTE)	Below 1 Ω
D5-2 (CLTB) - Body ground	10 kΩ or higher
D5-13 (CLTS) - Body ground	10 kΩ or higher
D5-14 (CLTE) - Body ground	10 kΩ or higher

NG: REPAIR OR REPLACE HARNESS AND CONNECTOR

OK: REPLACE DRIVER SIDE JUNCTION BLOCK