Toyota Corolla Cross Owners & Service Manuals

Toyota Corolla Cross: Headlight Control Module (Sub) System Internal Failure (B242C04,B242D04)

Toyota Corolla Cross (2022-2025) Service Manual / Vehicle Exterior / Lighting (ext) / Lighting System (w/ Afs) / Headlight Control Module (Sub) System Internal Failure (B242C04,B242D04)

DESCRIPTION

The headlight ECU sub-assembly LH or headlight ECU sub-assembly RH stores a DTC if it detects an internal malfunction.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

B242C04

Headlight Control Module (Sub) System Internal Failure

 Detection condition:
  • The ignition switch is ON
Malfunction status:
  • Headlight ECU sub-assembly RH internal malfunction
Malfunction duration:
  • Maximum 15 minutes

Headlight ECU sub-assembly RH

B242D04

Headlight Control Module (Main) System Internal Failure

 Detection condition:
  • The ignition switch is ON
Malfunction status:
  • Headlight ECU sub-assembly LH internal malfunction
Malfunction duration:
  • Maximum 15 minutes

Headlight ECU sub-assembly LH

CAUTION / NOTICE / HINT

NOTICE:

If the headlight ECU sub-assembly LH has been replaced, it is necessary to synchronize the vehicle information and initialize the headlight ECU sub-assembly LH.

Click here

PROCEDURE

1.

CLEAR DTC

(a) Clear the DTCs.

Body Electrical > Headlight Control > Clear DTCs Body Electrical > Headlight Control (Sub) > Clear DTCs
NEXT

2.

CHECK FOR DTC

(a) Turn the ignition switch to ON.

(b) Wait at least 15 minutes.

(c) Check for DTCs.

Body Electrical > Headlight Control > Trouble Codes Body Electrical > Headlight Control (Sub) > Trouble Codes

OK:

DTC B242C04 and B242D04 are not output.

Result

Proceed to

DTCs are not output

A

B242C04 is output

B

B242D04 is output

C
A

USE SIMULATION METHOD TO CHECK

B

REPLACE HEADLIGHT ECU SUB-ASSEMBLY RH

C

REPLACE HEADLIGHT ECU SUB-ASSEMBLY LH

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