DESCRIPTION
The DTC is stored when the main body ECU (driver side junction block assembly) detects malfunctions in the inner rear view mirror assembly.
| 
		 DTC No.  | 
		
		 DTC Detection Condition  | 
		
		 Trouble Area  | 
	
|---|---|---|
| 
		 B124A  | 
		
		 Malfunction in inner rear view mirror assembly  | 
		
		 Inner rear view mirror assembly  | 
	
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
First perform the communication function inspections in How to Proceed with Troubleshooting to confirm that there are no CAN communication malfunctions before troubleshooting this symptom.
PROCEDURE
| 
		 1.  | 
		
		 CHECK FOR DTC  | 
	
(a) Clear the DTCs (See page 
 ).
(b) Check for DTCs (See page 
 ).
OK:
DTC B124A is not output.
| OK |    | 
		 USE SIMULATION METHOD TO CHECK  | 
	
| NG |    | 
		 REPLACE INNER REAR VIEW MIRROR ASSEMBLY  | 
	
Lost Communication with ECM (U0101,U0073,U0126,U0129,U0142,U0182,U1000)
Automatic High Beam System (B124B)Removal
   	REMOVAL
CAUTION / NOTICE / HINT
PROCEDURE
1. PRECAUTION
NOTICE:
After turning the ignition switch off, waiting time may be required before disconnecting 
the cable from the negative (-) battery terminal. Therefore, make sure to read the 
disconnecting t ...
   	
Removal
   	REMOVAL
PROCEDURE
1. REMOVE ENGINE OIL LEVEL DIPSTICK GUIDE
	
		
		(a) Remove the engine oil level dipstick.
		
		
		
			
				
				
			
		
		
	
(b) Remove the bolt and engine oil level dipstick guide.
(c) Remove the O-ring from the engine  ...
   	
Initialization
   	INITIALIZATION
	NOTICE:
	
		Initialize the headlight leveling ECU assembly (set the zero point of 
		the height control sensor in the headlight leveling ECU assembly) after 
		the vehicle height changes due to replacement of the suspension or after 
		 ...