Toyota Avalon (XX50) 2019-2022 Service & Repair Manual: Rear Door Courtesy Switch Circuit

Toyota Avalon (XX50) 2019-2022 Service & Repair Manual / Vehicle Interior / Lighting (int) / Lighting System(for Gasoline Model) / Rear Door Courtesy Switch Circuit

DESCRIPTION

The main body ECU (multiplex network body ECU) detects the condition of the rear door courtesy light switch assembly.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

Before replacing the main body ECU (multiplex network body ECU), refer to Registration.

Click here

PROCEDURE

1.

READ VALUE USING TECHSTREAM

(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 / Main Body / Data List.

(e) Read the Data List according to the display on the Techstream.

Body Electrical > Main Body > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

RR Door Courtesy SW

Rear door courtesy light switch assembly (for RH) signal

OFF or ON

OFF: Rear door RH closed

ON: Rear door RH open

-

RL Door Courtesy SW

Rear door courtesy light switch assembly (for LH) signal

OFF or ON

OFF: Rear door LH closed

ON: Rear door LH open

-
Body Electrical > Main Body > Data List

Tester Display

RR Door Courtesy SW

RL Door Courtesy SW

OK:

Normal conditions listed above are displayed.

Result

Proceed to

OK

A

NG ("RR Door Courtesy SW" is not normal)

B

NG ("RL Door Courtesy SW" is not normal)

C
A

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

C

GO TO STEP 5

B

2.

INSPECT REAR DOOR COURTESY LIGHT SWITCH ASSEMBLY (for RH)

(a) Remove the rear door courtesy light switch assembly (for RH).

Click here

(b) Inspect the rear door courtesy light switch assembly (for RH).

Click here

NG

REPLACE REAR DOOR COURTESY LIGHT SWITCH ASSEMBLY (for RH)

OK

3.

CHECK HARNESS AND CONNECTOR (REAR DOOR COURTESY LIGHT SWITCH ASSEMBLY (for RH) - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)

(a) Disconnect the 4A instrument panel junction block assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

K8-1 - 4A-31

Always

Below 1 Ω

K8-1 or 4A-31 - Body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

4.

INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

*a

Component without harness connected (Instrument Panel Junction Block Assembly)

-

-

(a) Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.

Click here

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

4A-31 - MB-2 (RCTY)

Always

Below 1 Ω
OK

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

NG

REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

5.

INSPECT REAR DOOR COURTESY LIGHT SWITCH ASSEMBLY (for LH)

(a) Remove the rear door courtesy light switch assembly (for LH).

Click here

(b) Inspect the rear door courtesy light switch assembly (for LH).

Click here

NG

REPLACE REAR DOOR COURTESY LIGHT SWITCH ASSEMBLY (for LH)

OK

6.

CHECK HARNESS AND CONNECTOR (REAR DOOR COURTESY LIGHT SWITCH ASSEMBLY (for LH) - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)

(a) Disconnect the 4H instrument panel junction block assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

K9-1 - 4H-24

Always

Below 1 Ω

K9-1 or 4H-24 - Body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

7.

INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

*a

Component without harness connected (Instrument Panel Junction Block Assembly)

-

-

(a) Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.

Click here

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

4H-24 - MB-13 (LCTY)

Always

Below 1 Ω
OK

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

NG

REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

    Problem Symptoms Table

    System Description

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    Toyota Avalon (XX50) 2019-2022 Owners Manual

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