Last Modified: 07-31-2024 6.11:8.1.0 Doc ID: RM100000001GXJR
Model Year Start: 2020 Model: Corolla Prod Date Range: [01/2019 - 09/2022]
Title: LIGHTING (INT): LIGHTING SYSTEM (for HV Model): IG Signal Circuit; 2020 - 2022 MY Corolla Corolla HV [01/2019 - 09/2022]

IG Signal Circuit

DESCRIPTION

This circuit detects the power switch on (IG) 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.

    Click here 2020 - 2022 MY Corolla Corolla HV [01/2019 - 09/2022]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, HV Model): DTC CHECK / CLEAR

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

    Click here 2020 MY Corolla Corolla HV [01/2019 - 04/2020]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, HV Model): REGISTRATION 2021 - 2022 MY Corolla Corolla HV [04/2020 - 09/2022]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, HV Model): REGISTRATION

PROCEDURE

1.

READ VALUE USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

(b) Turn the power 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

IG SW

Power switch on (IG) signal

OFF or ON

OFF: Power switch off

ON: Power switch on (IG)

"OFF" is also displayed for this item when the power switch is on (ACC).

Body Electrical > Main Body > Data List

Tester Display

IG SW

OK:

Normal conditions listed above are displayed.

OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE 2020 MY Corolla Corolla HV [01/2019 - 04/2020]; LIGHTING (INT): LIGHTING SYSTEM (for HV Model): PROBLEM SYMPTOMS TABLE 2021 - 2022 MY Corolla Corolla HV [04/2020 - 09/2022]; LIGHTING (INT): LIGHTING SYSTEM (for HV Model): PROBLEM SYMPTOMS TABLE

NG

2.

CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY - POWER SOURCE AND BODY GROUND)

(a) Disconnect the 4D and 4F instrument panel junction block assembly connectors.

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

4D-1 - Body ground

Power switch off

11 to 14 V

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

4F-3 - Body ground

Always

Below 1 Ω

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

3.

CHECK HARNESS AND CONNECTOR (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) - BODY GROUND)

(a) Disconnect the I86 main body ECU (multiplex network body ECU) connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

I86-19 (GND2) - Body ground

Always

Below 1 Ω

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

4.

CHECK HARNESS AND CONNECTOR (IG1-NO. 1 RELAY POWER SOURCE)

*a

Component with harness connected

(Instrument Panel Junction Block Assembly)

-

-

(a) Connect the 4D and 4F instrument panel junction block assembly connectors.

(b) Connect the I86 main body ECU (multiplex network body ECU) connector.

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

4E-17 - Body ground

Power switch on (IG)

11 to 14 V

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

5.

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 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL 2020 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 09/2022]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

4F-3 - MB-11 (GND1)

Always

Below 1 Ω

4D-1 - MB-32 (IG)

Auxiliary battery not connected to 4E-17 and 4F-3

10 kΩ or higher

4D-1 - MB-32 (IG)

Auxiliary battery positive (+) → 4E-17

Auxiliary battery negative (-) → 4F-3

Below 1 Ω

OK

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL 2020 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 09/2022]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL

NG

REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL 2020 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 09/2022]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL