Toyota Yaris: Lighting System / Back Door Courtesy Switch Circuit

Toyota Yaris XP210 (2020-2026) Reapir and Service Manual / Vehicle Interior / Lighting (int) / Lighting System / Back Door Courtesy Switch Circuit

DESCRIPTION

The main body ECU (multiplex network body ECU) receives a back door open/closed signal from the back door courtesy light switch (back door lock assembly).

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

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

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PROCEDURE

1.

READ VALUE USING GTS

(a) Read the Data List according to the display on the GTS.

Body Electrical > Main Body > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Back Door Courtesy Switch Status

Back door courtesy switch signal

CLOSE or OPEN

CLOSE: Back door closed

OPEN: Back door open

-

Body Electrical > Main Body > Data List

Tester Display

Back Door Courtesy Switch Status

OK:

Normal conditions listed above are displayed.

OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

NG

2.

INSPECT BACK DOOR COURTESY LIGHT SWITCH (BACK DOOR LOCK ASSEMBLY)

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NG

REPLACE BACK DOOR COURTESY LIGHT SWITCH (BACK DOOR LOCK ASSEMBLY)

OK

3.

CHECK HARNESS AND CONNECTOR (BACK DOOR COURTESY LIGHT SWITCH (BACK DOOR LOCK ASSEMBLY) - POWER DISTRIBUTION BOX ASSEMBLY AND BODY GROUND)

(a) Disconnect the 4E power distribution box assembly connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

Y7-3(D+) - 4E-2

Always

Below 1 Ω

Y7-3(D+) or 4E-2 - Body ground

Always

10 kΩ or higher

Y7-2(ACT-) - Body ground

Always

Below 1 Ω

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

4.

INSPECT POWER DISTRIBUTION BOX ASSEMBLY

*a

Component without harness connected

(Power Distribution Box Assembly)

-

-

(a) Remove the main body ECU (multiplex network body ECU) from the power distribution box assembly.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

4E-2 - MB-19 (BCTY)

Always

Below 1 Ω

OK

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

NG

REPLACE POWER DISTRIBUTION BOX ASSEMBLY

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