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Inspection Procedure

WARNING: This page is about a different car, the 2003 Toyota Sequoia. However, it is still accessible from the selected car via links, so may be relevant.
  1. Check voltage between terminals TS and S5-3 of integration control and panel. 

    PREPARATION:

    Remove integration control and panel with connectors still connected.

    CHECK:

    1. Turn ignition switch to ON.
    2. Measure voltage between terminals TS and S5-3 of integration control and panel connector when the solar sensor is subjected to an electric light, and when the sensor is covered by a cloth.
      Fig 1: Measuring Voltage Between Terminals TS And S5-3 Of Integration Control And Panel Connector
      G02839061Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK:

    VOLTAGE REFERENCE

    Condition Voltage
    Sensor Subjected To Electric Light 0.8 - 4.3 V
    Sensor Covered By A Cloth Below 0.8 V
    NOTE: As the inspection light is moved away from the sensor, the voltage increases.
    1. NG : Go to step 2. 
    2. OK : Proceed to next circuit inspection shown in  PROBLEM SYMPTOMS TABLE  . However, if DTC 21 is displayed, check and replace integration control and panel. 
  2. Check solar sensor. 

    PREPARATION:

    Remove solar sensor.

    CHECK:

    1. Cover the sensor with a cloth.
    2. Measure resistance between terminals 1 and 2 of solar sensor connector.
    NOTE: Connect positive (+) lead of ohmmeter to terminal 1 and negative (-) lead to terminal 2 of the solar sensor.

    OK:

    1. Resistance : infinite Ω (no continuity) 
    Fig 2: Checking Solar Sensor
    G02839062Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    PREPARATION:

    1. Remove the cloth from the solar sensor and subject the sensor to electric light.
    2. Measure resistance.

    OK:

    1. Resistance: Approx. 4 kΩ (continuity) 
    NOTE: As the electric light is moved away from the sensor, the resistance increases.
    1. NG : Replace solar sensor. 
    2. OK : Go To Next Step. 
  3. Check harness and connector between solar sensor and integration control and panel (See  HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE  ). 
    1. NG : Repair or replace harness or connector. 
    2. OK : Check and replace integration control and panel.