LIGHTING SYSTEM(for Halogen Headlight), Diagnostic DTC:B1244

DESCRIPTION

The automatic light control sensor detects ambient light. The sensor creates an electrical signal based on the amount of light detected, and sends the signal to the main body ECU (multiplex network body ECU).

The main body ECU (multiplex network body ECU) turns on or off the headlights and taillights according to the signal.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

PROCEDURE

1. READ VALUE USING GTS

   
   

   1. Using the GTS, read the Data List.

      Click here

   2. According to the display on the GTS, read the Data List and check that the value of Light Sensor Illuminance changes while performing the following:

      
      

      1. Turn the light control switch to the Auto position.

      2. Cover the automatic light control sensor with an opaque object.

      3. Slowly move the opaque object to uncover and then cover the automatic light control sensor.

         Main Body

         Tester Display	Measurement Item / Range	Normal Condition	Diagnostic Note
         Light Sensor Illuminance	Light control sensor illuminance / 0 to 8191 lx	Value is output according to ambient light level	-

         OK
         The value changes according to the amount the automatic light control sensor is covered.

      Result
      Proceed to OK NG

   
   

   OK

   REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here

   NG

2. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU [MULTIPLEX NETWORK BODY ECU] - AUTOMATIC LIGHT CONTROL SENSOR)

   
   

   1. Disconnect the G217 main body ECU (multiplex network body ECU) connector.

   2. Disconnect the H84 automatic light control sensor connector.

   3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition G217-19 (CLTB) - H84-1 (CLTB) Always Below 1 Ω G217-20 (CLTS) - H84-4 (CLTS) Always Below 1 Ω G217-21 (CLTE) - H84-2 (CLTE) Always Below 1 Ω G217-19 (CLTB) or H84-1 (CLTB) - Body ground Always 10 kΩ or higher G217-20 (CLTS) or H84-4 (CLTS) - Body ground Always 10 kΩ or higher G217-21 (CLTE) or H84-2 (CLTE) - Body ground Always 10 kΩ or higher

      Result
      Proceed to OK NG

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

3. CHECK MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

   
   
   1. 

      *a	Component with harness connected (Main Body ECU [Multiplex Network Body ECU])

      Disconnect the H84 automatic light control sensor connector.

   2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition G217-19 (CLTB) - G217-21 (CLTE) Ignition switch off Below 1 V Ignition switch ON 11 to 14 V

      Result
      Proceed to OK NG

   
   

   NG

   REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here

   OK

4. CHECK AUTOMATIC LIGHT CONTROL SENSOR

   
   

   1. Using an oscilloscope, check the waveform.

      

      *a

      Component with harness connected (Main Body ECU [Multiplex Network Body ECU])

      *b

      Waveform

      OK
      Tester Connection Tool Setting Switch Condition Specified Condition G217-20 (CLTS) - G217-21 (CLTE) 2 V/DIV., 10 ms./DIV. Automatic light control system operating Pulse generation (Waveform)

      Tech Tips

      The communication waveform changes according to the surrounding brightness.

      Result
      Proceed to OK NG

   
   

   OK

   REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here

   NG

   REPLACE AUTOMATIC LIGHT CONTROL SENSOR Click here