Toyota Avalon (XX50) 2019-2022 Service & Repair Manual: Open in IG Circuit (B242E)

Toyota Avalon (XX50) 2019-2022 Service & Repair Manual / Vehicle Exterior / Lighting (ext) / Lighting System(for Gasoline Model With Cornering Light) / Open in IG Circuit (B242E)

DESCRIPTION

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-NO. 1 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.

HL AutoLeveling

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

DTC Output from

B242E

Open in IG Circuit
  • The engine switch is on (IG).
  • 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
  • 10 seconds or more
  • Headlight ECU sub-assembly LH
  • Harness or connector

Headlight ECU sub-assembly LH
HL AutoLeveling (Sub)

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

DTC Output from

B242E

Open in IG Circuit
  • The engine switch is on (IG).
  • 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
  • 10 seconds or more
  • Headlight ECU sub-assembly RH
  • Harness or connector

Headlight ECU sub-assembly RH

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • Inspect the fuses for circuits related to this system before performing the following procedure.
  • If the headlight ECU sub-assembly LH has been replaced, it is necessary to synchronize the vehicle information the headlight ECU sub-assembly LH.

    Click here

PROCEDURE

1.

CLEAR DTC

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / HL AutoLeveling or HL AutoLeveling (Sub) / Trouble Codes.

(e) Clear the DTCs.

Body Electrical > HL AutoLeveling > Clear DTCs Body Electrical > HL AutoLeveling (Sub) > Clear DTCs
NEXT

2.

CHECK FOR DTC

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG).

(c) Wait 10 seconds or more.

(d) Turn the Techstream on.

(e) Enter the following menus: Body Electrical / HL AutoLeveling or HL AutoLeveling (Sub) / Trouble Codes.

(f) Check for DTCs.

Body Electrical > HL AutoLeveling > Trouble Codes Body Electrical > HL AutoLeveling (Sub) > Trouble Codes

OK:

DTC B242E is not output.

Result

Proceed to

OK

A

NG (DTC output from headlight ECU sub-assembly LH)

B

NG (DTC output from headlight ECU sub-assembly RH)

C
A

USE SIMULATION METHOD TO CHECK

C

GO TO STEP 5

B

3.

INSPECT HEADLIGHT ECU SUB-ASSEMBLY LH (IG TERMINAL VOLTAGE)

*a

Front view of wire harness connector

(to Headlight ECU Sub-assembly LH)

(a) Disconnect the A8 headlight ECU sub-assembly LH connector.

(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection

Condition

Specified Condition

A8-4 (IG) - Body ground

Engine switch on (IG)

11 to 14 V
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

4.

CHECK HARNESS AND CONNECTOR (HEADLIGHT ECU SUB-ASSEMBLY LH - BODY GROUND)

(a) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

A8-12 (GND) - Body ground

Always

Below 1 Ω
OK

REPLACE HEADLIGHT ECU SUB-ASSEMBLY LH

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

5.

INSPECT HEADLIGHT ECU SUB-ASSEMBLY RH (IG TERMINAL VOLTAGE)

*a

Front view of wire harness connector

(to Headlight ECU Sub-assembly RH)

(a) Disconnect the A9 headlight ECU sub-assembly RH connector.

(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection

Condition

Specified Condition

A9-4 (IG) - Body ground

Engine switch on (IG)

11 to 14 V
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

6.

CHECK HARNESS AND CONNECTOR (HEADLIGHT ECU SUB-ASSEMBLY RH - BODY GROUND)

(a) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

A9-12 (GND) - Body ground

Always

Below 1 Ω
OK

REPLACE HEADLIGHT ECU SUB-ASSEMBLY RH

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
    Right Headlight ECU Malfunction (B242C,B242D)

    Open in B Power Line (B242F)

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