Last Modified: 07-31-2024 6.11:8.1.0 Doc ID: RM1000000026K07
Model Year Start: 2023 Model: GR Corolla Prod Date Range: [09/2022 - 11/2022]
Title: NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model except TMC Made): Restraints Occupant Classification System Module Communication Stop Mode; 2023 MY Corolla Corolla Hatchback GR Corolla [09/2022 - 11/2022]

Restraints Occupant Classification System Module Communication Stop Mode

DESCRIPTION

Detection Item

Symptom

Trouble Area

Restraints Occupant Classification System Module Communication Stop Mode

Any of the following conditions are met:

  • Communication stop for "Occupant Detection" is indicated on the "Communication Bus Check" screen of the Techstream.

    Click here 2023 MY Corolla Corolla Hatchback GR Corolla [09/2022 - 11/2022]; NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model except TMC Made): PROBLEM SYMPTOMS TABLE

  • Communication stop history for "Occupant Detection" is indicated on the "Communication Bus Check (Detail)" screen of the Techstream. (The Lost Communication Time value for "Occupant Detection" is 6 or more.)

    Click here 2023 MY Corolla Corolla Hatchback GR Corolla [09/2022 - 11/2022]; NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model except TMC Made): PROBLEM SYMPTOMS TABLE

  • Communication system DTCs (DTCs that start with U) that correspond to "Restraints Occupant Classification System Module Communication Stop Mode" in "DTC Combination Table" are output.

    Click here 2023 MY Corolla Corolla Hatchback GR Corolla [09/2022 - 11/2022]; NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model except TMC Made): DTC COMBINATION TABLE

  • Occupant detection ECU branch line or connector
  • Power source circuit of occupant detection ECU
  • Occupant detection ECU ground circuit
  • Occupant detection ECU

WIRING DIAGRAM

CAUTION / NOTICE / HINT

CAUTION:

When performing the confirmation driving pattern, obey all speed limits and traffic laws.

NOTICE:

  • Because the order of diagnosis is important to allow correct diagnosis, make sure to begin troubleshooting using How to Proceed with Troubleshooting when CAN communication system related DTCs are output.

    Click here 2023 MY Corolla Corolla Hatchback GR Corolla [09/2022 - 11/2022]; NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model except TMC Made): HOW TO PROCEED WITH TROUBLESHOOTING

  • Before measuring the resistance of the CAN bus, turn the ignition switch off and leave the vehicle for 1 minute or more without operating the key or any switches, or opening or closing the doors. After that, disconnect the cable from the negative (-) battery terminal and leave the vehicle for 10 minutes or more before measuring the resistance.
  • When disconnecting and reconnecting the battery.

    HINT:

    When disconnecting and reconnecting the battery, there is an automatic learning function that completes learning when the respective system is used.

    Click here 2023 MY Corolla Corolla Hatchback Corolla HV GR Corolla [09/2022 - 11/2022]; SETUP: WHEN DISCONNECTING OR RECONNECTING BATTERY TERMINAL: AUTOMATIC LEARNING CHART

  • Some parts must be initialized and set when replacing or removing and installing parts.

    Click here 2023 MY Corolla Corolla Hatchback Corolla HV GR Corolla [09/2022 - 11/2022]; SETUP: WHEN REPLACING OR REMOVING/INSTALLING PARTS: WORK PROCEDURE

  • After performing repairs, perform the DTC check procedure and confirm that the DTCs are not output again.

    DTC check procedure: Turn the ignition switch to ON and wait for 1 minute or more. Then operate the suspected malfunctioning system and drive the vehicle at 60 km/h (37 mph) or more for 5 minutes or more.

  • After the repair, perform the CAN bus check and check that all the ECUs and sensors connected to the CAN communication system are displayed as normal.

    Click here 2023 MY Corolla Corolla Hatchback GR Corolla [09/2022 - 11/2022]; NETWORKING: CAN COMMUNICATION SYSTEM (for Gasoline Model except TMC Made): DIAGNOSIS SYSTEM

  • Inspect the fuses for circuits related to this system before performing the following procedure.

HINT:

  • Before disconnecting related connectors for inspection, push in on each connector body to check that the connector is not loose or disconnected.
  • When a connector is disconnected, check that the terminals and connector body are not cracked, deformed or corroded.

PROCEDURE

1.

CHECK FOR OPEN IN CAN BUS LINES (OCCUPANT DETECTION ECU BRANCH LINE)

(a) Disconnect the cable from the negative (-) battery terminal.

(b) Disconnect the j4 occupant detection ECU connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

j4-5 (CANH) - j4-4 (CANL)

Cable disconnected from negative (-) battery terminal

54 to 69 Ω

*a

Front view of wire harness connector

(to Occupant Detection ECU)
NG

REPAIR OR REPLACE CAN BRANCH LINES OR CONNECTOR (OCCUPANT DETECTION ECU)
OK

2.

CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT)

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

j4-10 (GND) - Body ground

Cable disconnected from negative (-) battery terminal

Below 1 Ω

*a

Front view of wire harness connector

(to Occupant Detection ECU)

(b) Reconnect the cable to the negative (-) battery terminal.

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

j4-6 (IG2) - Body ground

Ignition switch ON

11 to 14 V
OK

REPLACE OCCUPANT DETECTION ECU

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)