METER / GAUGE SYSTEM > Meter Illumination is Always Dark

for Preparation Click here


DESCRIPTION

The meter ECU receives signals from this circuit to adjust the illumination of the meter. The meter ECU sets the illumination level based on the user operation of the light control rheostat.

HINT:
  1. The meter illumination level can be adjusted by operating the light control rheostat.
  2. The meter illumination dims when the light control switch is turned to the tail, head, or AUTO position at night.
  3. Setting the meter illumination to maximum brightness cancels the above dimming of the meter illumination.


WIRING DIAGRAM


E165892E28


INSPECTION PROCEDURE

HINT:
  1. The meter illumination can be customized by turning the light control rheostat.
  2. Before starting following inspection, check if the lighting system outputs the DTCs (Click here).

1.CHECK CAN COMMUNICATION SYSTEM

  1. Check if a CAN communication DTC is output (Click here).

    Result:

    Result
    		Proceed to
    CAN communication DTC is not output.
    		A
    CAN communication DTC is output.
    		B



B
GO TO CAN COMMUNICATION SYSTEM (Click here)
A


2.READ VALUE USING INTELLIGENT TESTER (ILLUMINATION RATE INFO)

  1. Connect the intelligent tester to the DLC3.

  1. Turn the power switch on (IG).

  1. Turn the intelligent tester on.

  1. Enter the following menus: Body / Main Body / Data List.

  1. Check the values by referring to the table below.

    Main Body 
    Tester Display
    		Measurement Item/Range
    		Normal Condition
    		Diagnostic Note
    Illumination Rate Info
    		Illumination rate information/0 ms to 2162.65 ms
    		Value output according to ambient light levels
    		-

    Result:

    Result
    		Proceed to
    The output value changes according to the ambient light levels.
    		A
    The output value does not change according to the ambient light levels.
    		B



B
CHECK LIGHTING SETTING (Click here)
A


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

  1. Replace the main body ECU (multiplex network body ECU) with a new or a normal one (Click here).

    OK:
    The operation of the combination meter assembly returns to normal.

    HINT:
    The meter ECU controls the meter illumination based on an auto dimmer signal from the main body ECU (multiplex network body ECU). When the meter illumination is always dark (very dim), it may be due to the main body ECU (multiplex network body ECU) sending an auto dimmer signal to the meter ECU because of a malfunction in the main body ECU (multiplex network body ECU).



NG
REPLACE COMBINATION METER ASSEMBLY (Click here)
OK

END