Meter Illumination Does Not Dim At Night
METER: METER / GAUGE SYSTEM: Meter Illumination does not Dim at Night
- Meter Illumination does not Dim at Night
DESCRIPTION
In this circuit, the meter CPU receives auto dimmer signals from the main body ECU using the CAN communication lines (CAN MS Bus). When the meter CPU 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 automatic light control sensor, main body ECU, CAN communication system, wire harness or connector, or combination meter assembly.
WIRING DIAGRAM
INSPECTION PROCEDURE
PROCEDURE
1. CHECK CAN COMMUNICATION SYSTEM
(a) Check if CAN communication DTC is output Diagnosis System.
Result:
B -- GO TO CAN COMMUNICATION SYSTEM
A -- Continue to next step.
2. CHECK DTC
(a) Check if DTC B1244 is output Reading and Clearing Diagnostic Trouble Codes.
Result:
B -- GO TO LIGHTING SYSTEM
A -- Continue to next step.
3. PERFORM ACTIVE TEST USING TECHSTREAM
(a) Connect Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the tester ON.
(d) Turn the light control rheostat to the TAIL or HEAD position.
(e) Enter the following menus: Body Electrical / Main Body / Active Test.
(f) Check the meter illumination.
Main Body:
OK:
The meter illumination is dimmed when the dimmer signal is ON.
HINT
Refer to the sensitivity setting in the customization table of the lighting system Customize Parameters.
NG -- REPLACE COMBINATION METER ASSEMBLY
OK -- CHECK LIGHTING SETTING
4. REPLACE COMBINATION METER ASSEMBLY
(a) Replace the combination meter assembly with a new or a normal one.
OK:
The operation of the combination meter assembly returns to normal.
NG -- REPLACE MAIN BODY ECU
OK -- END