DTC B124B: Automatic High Beam System [08/2013 - ]: Procedure
WARNING: This page is about a different car, the 2014 Lexus ES 300h. However, it is still accessible from the selected car via links, so may be relevant.
- CHECK FOR DTC (AUTOMATIC HIGH BEAM SYSTEM)
- Clear the DTCs. Refer to DTC CHECK / CLEAR [08/2013 - ] .
- Check for DTCs. Refer to DTC CHECK / CLEAR [08/2013 - ]
.
OK
DTC B124B is not output.
Result
Result Proceed to DTC B124B is not output A DTC B124B is output
(w/ Dynamic Radar Cruise Control System)B DTC B124B is output
(w/o Dynamic Radar Cruise Control System)C
B → See step 2
C → See step 5
A → See step 8
- CHECK FOR DTC (LANE DEPARTURE ALERT SYSTEM)
- Check for DTCs. Refer to DTC CHECK / CLEAR [08/2013 - ]
.
Result
Result Proceed to Lane departure alert system DTCs are not output A Lane departure alert system DTCs are output B CAN communication system DTCs are output C
B → See step 7
C → See step 10
A: Go to next step
- Check for DTCs. Refer to DTC CHECK / CLEAR [08/2013 - ]
.
- REPLACE LANE DEPARTURE WARNING CAMERA
- Replace the lane departure warning camera with a new or known good one. Refer to REMOVAL [08/2013 - ] .
- Check for DTCs. Refer to DTC CHECK / CLEAR [08/2013 - ]
.
OK
DTC B124B is not output.
NG → See step 4
OK → END (LANE DEPARTURE WARNING CAMERA WAS DEFECTIVE)
- REPLACE DRIVING SUPPORT ECU ASSEMBLY
- Replace the driving support ECU assembly with a new or known good one. Refer to REMOVAL [08/2013 - ] .
- Check for DTCs. Refer to DTC CHECK / CLEAR [08/2013 - ]
.
OK
DTC B124B is not output.
NG → See step 11
OK → END (DRIVING SUPPORT ECU ASSEMBLY WAS DEFECTIVE)
- CHECK FOR DTC (LANE DEPARTURE ALERT SYSTEM)
- Check for DTCs. Refer to DTC CHECK / CLEAR [08/2013 - ]
.
Result
Result Proceed to Lane departure alert system DTCs are not output A Lane departure alert system DTCs are output B CAN communication system DTCs are output C
B → See step 9
C → See step 10
A: Go to next step
- Check for DTCs. Refer to DTC CHECK / CLEAR [08/2013 - ]
.
- REPLACE LANE DEPARTURE WARNING CAMERA
- Replace the lane departure warning camera with a new or known good one. Refer to REMOVAL [08/2013 - ] .
- Check for DTCs. Refer to DTC CHECK / CLEAR [08/2013 - ]
.
OK
DTC B124B is not output.
NG → See step 11
OK → END (LANE DEPARTURE WARNING CAMERA WAS DEFECTIVE)
- GO TO LANE DEPARTURE ALERT SYSTEM. Refer to DIAGNOSTIC TROUBLE CODE CHART [08/2013 - ]
- USE SIMULATION METHOD TO CHECK. Refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2013 - ]
- GO TO LANE DEPARTURE ALERT SYSTEM. Refer to DIAGNOSTIC TROUBLE CODE CHART [08/2013 - ]
- GO TO CAN COMMUNICATION SYSTEM. Refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2013 - ]
- REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU). Refer to REMOVAL [08/2013 - ]