Toyota Yaris: Lighting System / Parking Brake Switch Circuit

Toyota Yaris XP210 (2020-2026) Reapir and Service Manual / Vehicle Exterior / Lighting (ext) / Lighting System / Parking Brake Switch Circuit

DESCRIPTION

The main body ECU (multiplex network body ECU) detects the condition of the parking brake switch 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

Parking Brake Switch

Parking brake switch signal

Release or Lock

Release: Parking brake released

Lock: ON: Parking brake applied

-

Body Electrical > Main Body > Data List

Tester Display

Parking Brake Switch

OK:

Normal conditions listed above are displayed.

OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

NG

2.

INSPECT PARKING BRAKE SWITCH ASSEMBLY

Click here

NG

REPLACE PARKING BRAKE SWITCH ASSEMBLY

OK

3.

CHECK HARNESS AND CONNECTOR (PARKING BRAKE SWITCH ASSEMBLY - POWER DISTRIBUTION BOX ASSEMBLY)

(a) Disconnect the 4B 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

H37-1 (+) - 4B-13

Always

Below 1 Ω

H37-1 (+) or 4B-13 - Body ground

Always

10 kΩ or higher

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

4B-13 - MB-21 (PKB)

Always

Below 1 Ω

OK

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

NG

REPLACE POWER DISTRIBUTION BOX ASSEMBLY

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    Categories

    Turning the Engine Off

    Stop the vehicle completely. Manual transaxle: Shift into neutral and set the parking brake.

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