Inspection Procedure

HINT:

In case of using the LEXUS hand-held tester, start the inspection step 1 and in case of not using the hand-held tester, start from step  2.

1. Check solar sensor using LEXUS hand-held tester. 

   PREPARATION: 

   Connect the LEXUS hand-held tester to the DLC3.

   CHECK: 

   Check the solar sensor using DATA LIST.

   1. OK : Check and replace A/C ECU. 
   2. NG : Go to next step. 
2. Check voltage between terminals TSDr and GND of A/C ECU connector. 

   PREPARATION: 

   Remove A/C ECU with connectors still connected.

   CHECK: 

   1. Turn ignition switch to ON.
   2. Measure voltage between terminals TSDr and GND of A/C ECU connector when the solar sensor is subjected to an electric light, and when the sensor is covered by a cloth.
      Fig 1: Identifying Solar Sensor Using Lexus Hand-Held Tester

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   OK: 

   VOLTAGE CONDITION SPECIFICATION
   
   

   Condition	Voltage
   Sensor subjected to electric light	0.8 - 4.3 V
   Sensor covered by a cloth	Below 0.8 V

   HINT:

   As the inspection light is moved away from the sensor, the voltage increases.

   1. NG : Go to step 3. 
   2. OK : Proceed to next circuit inspection shown on problem symptoms table (See  PROBLEM SYMPTOMS TABLE  ). However, if DTC B1424/24 is displayed, check and replace A/C ECU. 
3. Check wire harness 

   PREPARATION: 

   Disconnect the connector of solar sensor and A/C ECU.

   CHECK: 

   Check the continuity between wire harness and body ground.

   OK: 

   Resistance: No continuity 

   Fig 2: Checking Wiring Harness

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. NG : Repair or replace the wire harness. 
   2. OK : Go to next step. 
4. Check A/C ECU. 

   PREPARATION: 

   Connect the connector of A/C ECU.

   CHECK: 

   Check the DTC.

   OK: 

   B1224/24 is not output.

   Fig 3: Checking A/C ECU

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. NG : Replace the A/C ECU. 
   2. OK : Replace the solar sensor.