Meter Illumination Is Always Dark

METER: METER / GAUGE SYSTEM: Meter Illumination is Always Dark
- Meter Illumination is Always Dark

DESCRIPTION

In this circuit, the combination meter receives auto dimmer signals from the main body ECU using the CAN communication lines. When the combination meter receives an auto dimmer signal, it dims the meter illumination. The main body ECU determines whether it is daytime, twilight or nighttime based on the waveform transmitted from the automatic light control sensor. If the main body ECU determines that it is daytime, the ECU does not send auto dimmer signals. Therefore, the meter illumination (warning and indicator lights) will not dim even if the driver accidentally turns the light control switch to the TAIL or HEAD position in daytime.

HINT
When the meter illumination does not dim at night, the light control rheostat position is at the tail cancel position, or there may be a malfunction in the automatic light control sensor, main body ECU, CAN communication system, wire harness or connector, or combination meter.

WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK CAN COMMUNICATION SYSTEM

(a) Check for the DTC Reading and Clearing Diagnostic Trouble Codes.

Result





B -- Go to CAN COMMUNICATION SYSTEM CAN Communication System

C -- Go to LIGHTING SYSTEM Lighting System
A -- Continue to next step.

2. PERFORM ACTIVE TEST USING TECHSTREAM (DIMMER SWITCH)

(a) Operate the Techstream according to the display and select "Active Test".

Main Body:





OK:

Meter illumination is dimmed when the dimmer switch is ON.

HINT
Refer to the sensitivity setting in the customization table of the automatic light control system Programming and Relearning.

NG -- REPLACE COMBINATION METER ASSEMBLY

OK -- CHECK LIGHTING SETTING Programming and Relearning

3. REPLACE COMBINATION METER ASSEMBLY

(a) Temporarily replace the combination meter with a new one Removal.

NEXT -- Continue to next step.

4. CHECK COMBINATION METER ASSEMBLY

(a) Check that the operation of the combination meter returns to normal Removal.

OK:

Operation of combination meter returns to normal.

NG -- REPLACE MAIN BODY ECU (DRIVER SIDE JUNCTION BLOCK)

OK -- END (COMBINATION METER IS DEFECTIVE)