Toyota Corolla Cross Owners & Service Manuals

Toyota Corolla Cross: IG Signal Circuit

DESCRIPTION

This circuit detects the ignition switch ON or off condition, and sends it to the main body ECU (multiplex network body ECU).

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • Inspect the fuses for circuits related to this system before performing the following procedure.
  • First, check for smart key system (for Start Function) DTCs, and after confirming that there is no malfunction, proceed with troubleshooting.*1

    for HEV Model: Click here

    for Gasoline Model: Click here

  • Before replacing the main body ECU (multiplex network body ECU), refer to Registration.*1
    • *1: w/ Smart key System

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

IGR Power

Ignition switch ON signal

OFF or ON

OFF: Ignition switch off

ON: Ignition switch ON

-

Body Electrical > Main Body > Data List

Tester Display

IGR Power

OK:

Normal conditions listed above are displayed.

OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

NG

2.

CHECK HARNESS AND CONNECTOR (POWER DISTRIBUTION BOX ASSEMBLY - POWER SOURCE)

(a) Disconnect the 8C and 8K power distribution box assembly connectors.

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

8K-1 - Body ground

Ignition switch off

11 to 14 V

8C-17 - Body ground

Ignition switch off

Below 1 V

8C-17 - Body ground

Ignition switch ON

11 to 14 V

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

3.

CHECK HARNESS AND CONNECTOR (POWER DISTRIBUTION BOX ASSEMBLY - BODY GROUND)

(a) Disconnect the 8B and 8C power distribution box assembly connectors.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

8B-36 - Body ground

Always

Below 1 Ω

8C-41 - 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.

Click here

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

8B-36 - MB-13 (GND1)

Always

Below 1 Ω

8C-41 - MB-14 (GND2)

Always

Below 1 Ω

8K-1 - MB-27 (IGR)

Auxiliary battery not connected to 8C-17 - 8B-36 or 8C-41

10 kΩ or higher

8K-1 - MB-27 (IGR)

Auxiliary battery positive (+) → 8C-17

Auxiliary battery negative (-) → 8B-36 or 8C-41

Below 1 Ω

OK

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

NG

REPLACE POWER DISTRIBUTION BOX ASSEMBLY

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