DTC B242E: Open in IG Circuit [09/2020 - ]: Description

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

The IG terminal power source voltage is supplied by turning the IG1 relay to ON.

The headlight ECU sub-assembly receives engine switch on (IG) signals from the main body ECU (multiplex network body ECU) via CAN communication, compares the engine switch on (IG) signal and the power source voltage supply condition of the IG terminal and monitors the result.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	DTC Output from
B242E	Open in IG Circuit	Detection condition: The engine switch is on (IG). Malfunction status: When the IG terminal power source voltage is 0 V (engine switch off), IG ON signals from the main body ECU (multiplex network body ECU) via CAN communication are continuously received Malfunction duration: 10 seconds or more	Headlight ECU sub-assembly LH Harness or connector	HL AutoLeveling

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

DTC Output from

B242E

Open in IG Circuit

Detection condition:

The engine switch is on (IG).

Malfunction status:

When the IG terminal power source voltage is 0 V (engine switch off), IG ON signals from the main body ECU (multiplex network body ECU) via CAN communication are continuously received

Malfunction duration:

10 seconds or more

Headlight ECU sub-assembly LH
Harness or connector

HL AutoLeveling