DESCRIPTION
In this circuit, the combination meter assembly auto dimmer signals from the main body ECU using the CAN communication system (CAN V1 Bus). When the combination meter assembly an auto dimmer signal, it dims the meter illumination (warning and indicator lights). The main body ECU (multiplex network 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 (multiplex network body ECU) determines that it is nighttime and the light control switch is in the tail, head, or AUTO, the ECU sends an auto dimmer signal. According to the signal, the combination meter assembly dims the meter illumination.
HINT:
When the meter illumination does not dim at night, there may be a malfunction in the automatic light control sensor, main body ECU (multiplex network body ECU), CAN communication system, harness or connector, or combination meter assembly.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
HINT:
NOTICE:
PROCEDURE
1. |
CHECK CAN COMMUNICATION SYSTEM |
(a) Check if a CAN communication DTC is output (See page
).
Result |
Proceed to |
---|---|
CAN communication DTC is not output |
A |
CAN communication DTC is output |
B |
B | ![]() |
GO TO CAN COMMUNICATION SYSTEM |
|
2. |
CONFIRM DTC OUTPUT (LIGHT CONTROL SENSOR CIRCUIT) |
(a) Check if DTC B1244 is output (See page
).
Result |
Proceed to |
---|---|
B1244 is not output |
A |
B1244 is output |
B |
B | ![]() |
GO TO LIGHTING SYSTEM |
|
3. |
CHECK OPERATION (AUTOMATIC LIGHT CONTROL SYSTEM) |
(a) Turn the ignition switch to ON.
(b) Turn the light control switch to the AUTO position.
(c) Cover the automatic light control sensor.
(d) Check that the taillights and low beam headlights.
OK:
The taillights and low beam headlights come on.
(e) Uncover the automatic light control sensor.
(f) Check that the low beam headlights and taillights.
OK:
The low beam headlights and taillights go off.
Result
Result |
Proceed to |
---|---|
Automatic light control system operates normally |
A |
Automatic light control system does not operate normally |
B |
B | ![]() |
CHECK LIGHTING SETTING |
|
4. |
REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) |
(a) Replace the main body ECU (multiplex network body ECU) with a new or a normal
one (See page ).
OK:
The operation of the combination meter assembly returns to normal.
HINT:
The combination meter assembly controls the meter illumination based on an auto dimmer signal from the main body ECU (multiplex network body ECU). If the meter does not dim when the light control switch is in the tail, head, or AUTO position at night, it may be for either of 2 reasons. The first reason is that the main body ECU (multiplex network body ECU) does not send an auto dimmer signal. The second is that the meter CPU does not dim the meter illumination even though the meter CPU receives an auto dimmer signal.
OK | ![]() |
END (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) WAS DEFECTIVE) |
NG | ![]() |
REPLACE COMBINATION METER ASSEMBLY |
Short to +B in Buzzer (C1ABD,C1ABE)
DESCRIPTION
DTC C1ABD is stored when the blind spot monitor sensor RH detects a
+B short in rear cross traffic alert buzzer (blind spot monitor buzzer)
circuit.
DTC C1ABE is stored when the blind spot monitor sensor RH detects a
ground short or open in rear cross traffic aler ...
Operation Check
OPERATION CHECK
1. MALFUNCTION DISPLAY (MULTI-INFORMATION DISPLAY)
(a) Open circuit indication
(1) If there is an open circuit between a No. 1 ultrasonic sensor and the clearance
warning ECU assembly or a sensor is malfunctioning, the malfunction is displayed
as shown in the illustration.
...
Replacement
REPLACEMENT
PROCEDURE
1. RECOVER REFRIGERANT FROM REFRIGERATION SYSTEM
(a) Start up the engine.
(b) Turn the A/C switch to ON.
(c) Operate the cooler compressor with an engine speed of approximately 1,000
rpm for 5 to 6 minutes to circulate the refrigerant and collect the compressor oil
rem ...