Last Modified: 11-20-2023 6.11:8.1.0 Doc ID: RM1000000012UH9
Model Year Start: 2018 Model: Camry Prod Date Range: [03/2017 -           ]
Title: LIGHTING (INT): LIGHTING SYSTEM: IG Signal Circuit; 2018 - 2024 MY Camry [03/2017 -        ]

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.*

    Click here 2018 - 2022 MY Camry [03/2017 - 08/2022]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function): DTC CHECK / CLEAR 2023 - 2024 MY Camry [08/2022 -        ]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function): DTC CHECK / CLEAR

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

    Click here 2018 - 2019 MY Camry [03/2017 - 09/2019]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function): REGISTRATION 2020 - 2022 MY Camry [09/2019 - 08/2022]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function): REGISTRATION 2023 - 2024 MY Camry [08/2022 -        ]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function): REGISTRATION

  • *: w/ Smart Key System

PROCEDURE

1.

READ VALUE USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(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

Ignition switch ON signal

OFF or ON

OFF: Ignition switch off

ON: Ignition switch ON

"OFF" is also displayed for this item when the ignition switch is 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 2018 MY Camry [03/2017 - 06/2017]; LIGHTING (INT): LIGHTING SYSTEM: PROBLEM SYMPTOMS TABLE 2018 - 2019 MY Camry [06/2017 - 09/2019]; LIGHTING (INT): LIGHTING SYSTEM: PROBLEM SYMPTOMS TABLE 2020 - 2021 MY Camry [09/2019 - 08/2021]; LIGHTING (INT): LIGHTING SYSTEM: PROBLEM SYMPTOMS TABLE 2022 - 2024 MY Camry [08/2021 -        ]; LIGHTING (INT): LIGHTING SYSTEM: PROBLEM SYMPTOMS TABLE

NG

2.

CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT)

(a) Disconnect the 3F instrument panel junction block assembly connector.

(b) Disconnect the 3B instrument panel junction block assembly connector.

(c) Disconnect the K51 main body ECU (multiplex network body ECU) connector.

(d) Measure the voltage and resistance according to the value(s) in the table below.

Standard Voltage:

Tester Connection

Condition

Specified Condition

3F-1 - Body ground

Always

11 to 14 V

Standard Resistance:

Tester Connection

Condition

Specified Condition

3B-3 - Body ground

Always

Below 1 Ω

K51-19 (GND2) - Body ground

Always

Below 1 Ω

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

3.

INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

*a

Component without harness connected

(Instrument Panel Junction Block Assembly)

-

-

(a) Remove the instrument panel junction block assembly.

Click here 2018 MY Camry [03/2017 - 06/2017]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL 2018 - 2020 MY Camry [06/2017 - 10/2020]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL 2021 - 2024 MY Camry [10/2020 -        ]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL

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

Click here 2018 MY Camry [03/2017 - 06/2017]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL 2018 - 2020 MY Camry [06/2017 - 10/2020]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL 2021 - 2024 MY Camry [10/2020 -        ]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

3F-1 - MB-32 (IG)

Battery not connected to 3A-17 and 3B-3

10 kΩ or higher

3F-1 - MB-32 (IG)

Battery positive (+) → 3A-17

Battery negative (-) → 3B-3

Below 1 Ω

OK

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) 2018 MY Camry [03/2017 - 06/2017]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL 2018 - 2020 MY Camry [06/2017 - 10/2020]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL 2021 - 2024 MY Camry [10/2020 -        ]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL

NG

REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY 2018 MY Camry [03/2017 - 06/2017]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL 2018 - 2020 MY Camry [06/2017 - 10/2020]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL 2021 - 2024 MY Camry [10/2020 -        ]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL