DTC B242F: Open in B Power Line [12/2019 - 11/2023]: Description

The headlight ECU sub-assembly operates using the power source voltage input from the IG terminal and ECUB terminal.

The power source voltage of the ECUB terminal is supplied when the main body ECU (multiplex network body ECU) turns the ECUB power supply relay (H-LP LH relay and H-LP RH relay) to ON.

The headlight ECU sub-assembly compares the power source voltage supply condition of the IG terminal and ECUB terminal and monitors the result.

AFS

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	DTC Output from
B242F	Open in B Power Line	Detection condition: The ignition switch is ON. Malfunction status: No power source voltage supplied to ECUB terminal while power source voltage being supplied to IG terminal Malfunction duration: 10 seconds or more	Headlight ECU sub-assembly LH Harness or connector H-LP LH relay Instrument panel junction block assembly Main body ECU (multiplex network body ECU)	AFS

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

DTC Output from

B242F

Open in B Power Line

Detection condition:

The ignition switch is ON.

Malfunction status:

No power source voltage supplied to ECUB terminal while power source voltage being supplied to IG terminal

Malfunction duration:

10 seconds or more

Headlight ECU sub-assembly LH
Harness or connector
H-LP LH relay
Instrument panel junction block assembly
Main body ECU (multiplex network body ECU)

AFS

AFS (SUB)

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	DTC Output from
B242F	Open in B Power Line	Detection condition: The ignition switch is ON. Malfunction status: No power source voltage supplied to ECUB terminal while power source voltage being supplied to IG terminal Malfunction duration: 10 seconds or more	Headlight ECU sub-assembly RH Harness or connector H-LP RH relay Main body ECU (multiplex network body ECU)	AFS (Sub)