Last Modified: 05-13-2024 6.11:8.1.0 Doc ID: RM100000002B350
Model Year Start: 2023 Model: Corolla Hatchback Prod Date Range: [03/2023 -           ]
Title: K120 / K121 (CVT): K121 CONTINUOUSLY VARIABLE TRANSAXLE SYSTEM: CHECK FOR INTERMITTENT PROBLEMS; 2023 - 2025 MY Corolla Corolla Hatchback [03/2023 -        ]

CHECK FOR INTERMITTENT PROBLEMS

HINT:

Troubleshoot malfunctions with the ECM in check mode. Intermittent problems are easier to detect with the GTS when the ECM is in check mode. In check mode, the ECM uses 1-trip detection logic, which is more sensitive to malfunctions than normal mode (default), which uses 2-trip detection logic.

  1. Clear the DTCs.

    Click here 2023 - 2025 MY Corolla Corolla Hatchback [03/2023 -        ]; K120 / K121 (CVT): K121 CONTINUOUSLY VARIABLE TRANSAXLE SYSTEM: DTC CHECK / CLEAR

  2. Switch the ECM from normal mode to check mode using the GTS.

    Click here 2023 - 2025 MY Corolla Corolla Hatchback [03/2023 -        ]; K120 / K121 (CVT): K121 CONTINUOUSLY VARIABLE TRANSAXLE SYSTEM: CHECK MODE PROCEDURE

  3. Perform a simulation test.

    Click here 2019 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [06/2018 -        ]; INTRODUCTION: HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS: HOW TO PROCEED WITH TROUBLESHOOTING

  4. Check and wiggle the harnesses, connectors and terminals.

    Click here 2019 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [06/2018 -        ]; INTRODUCTION: HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS: ELECTRONIC CIRCUIT INSPECTION PROCEDURE