LIGHTING SYSTEM Instrument Panel Illumination Remains On

WIRING DIAGRAM

Refer to the wiring diagram for "Instrument Panel Illumination does not Turn On" Click here

CAUTION / NOTICE / HINT

Note

Inspect the fuses for circuits related to this system before performing the following inspection procedure.

PROCEDURE


  1. CHECK WAVEFORM


    1. A000ZU5E02
      *1 Component with harness connected: (to No. 1 Instrument Panel Garnish [Passenger Side Instrument Panel Illumination])

      Using an oscilloscope, measure the waveform of the connector 60 seconds after the door has been locked.

      A001062E01
      *1 Waveform 1
      *2 Waveform 2
      *3 Waveform 3
      *4 Waveform 4
      Waveform 1
      Item Content
      Terminal No. (Symbol) L171-2 (INP1) - Body ground
      Tool Setting 2 V/DIV., 5 ms/DIV.
      Condition Instrument panel illumination is off (when in sleep mode [60 seconds or more have passed since the doors were locked])
      Waveform 2
      Item Content
      Terminal No. (Symbol) L171-1 (INP2) - Body ground
      Tool Setting 2 V/DIV., 5 ms/DIV.
      Condition Instrument panel illumination is off (when in sleep mode [60 seconds or more have passed since the doors were locked])
      Waveform 3
      Item Content
      Terminal No. (Symbol) L171-9 (INP3) - Body ground
      Tool Setting 2 V/DIV., 5 ms/DIV.
      Condition Instrument panel illumination is off (when in sleep mode [60 seconds or more have passed since the doors were locked])
      Waveform 4
      Item Content
      Terminal No. (Symbol) L171-10 (INP4) - Body ground
      Tool Setting 2 V/DIV., 5 ms/DIV.
      Condition Instrument panel illumination is off (when in sleep mode [60 seconds or more have passed since the doors were locked])
      OK
      The output waveform does not resemble the waveform shown in the illustration.

      Tech Tips

      A waveform will not be output if the main body ECU is operating normally.


    OK

    REPLACE NO. 1 INSTRUMENT PANEL GARNISH SUB-ASSEMBLY (PASSENGER SIDE INSTRUMENT PANEL ILLUMINATION) Click here

    NG

  2. CHECK MAIN BODY ECU (DRIVER SIDE JUNCTION BLOCK ASSEMBLY)


    1. Temporarily replace the main body ECU with a new or normally functioning one.

    2. Operate the instrument panel illumination and check the illumination condition.

      OK
      Instrument panel illumination operation is normal

    OK

    END (MAIN BODY ECU WAS DEFECTIVE)

    NG

    REPLACE NO. 1 INSTRUMENT PANEL GARNISH SUB-ASSEMBLY (PASSENGER SIDE INSTRUMENT PANEL ILLUMINATION) Click here