Last Modified: 05-13-2024 6.11:8.1.0 Doc ID: RM1000000026K01
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): Certification ECU Communication Stop Mode; 2023 MY Corolla Corolla Hatchback GR Corolla [09/2022 - 11/2022]

Certification ECU Communication Stop Mode

DESCRIPTION

Detection Item

Symptom

Trouble Area

Certification ECU Communication Stop Mode

Any of the following conditions are met:

  • Communication stop for "Certification (Smart)" 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 "Certification (Smart)" is indicated on the "Communication Bus Check (Detail)" screen of the Techstream. (The Lost Communication Time value for "Certification (Smart)" 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 "Certification ECU 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

  • Certification ECU (smart key ECU assembly) branch line or connector
  • Power source circuit of certification ECU (smart key ECU assembly)
  • Certification ECU (smart key ECU assembly) ground circuit
  • Certification ECU (smart key ECU assembly)

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 engine 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 1 minute 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 engine switch on (IG) 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.
  • Before replacing the certification ECU (smart key ECU assembly), refer to Registration.

    Click here 2023 MY Corolla Corolla Hatchback GR Corolla [09/2022 - 11/2022]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function (Gasoline Model, TMMMS Made)): REGISTRATION

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 (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) BRANCH LINE)

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

(b) Disconnect the I1 certification ECU (smart key ECU assembly) connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

I1-1 (CANH) - I1-2 (CANL)

Cable disconnected from negative (-) battery terminal

54 to 69 Ω

*a

Front view of wire harness connector

(to Certification ECU (Smart Key ECU Assembly))
NG

REPAIR OR REPLACE CAN BRANCH LINES OR CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY))
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

I1-18 (E) - Body ground

Cable disconnected from negative (-) battery terminal

Below 1 Ω

*a

Front view of wire harness connector

(to Certification ECU (Smart Key ECU Assembly))

(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

I1-3 (+B) - Body ground

Always

11 to 14 V
OK

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)