Toyota Corolla Cross Owners & Service Manuals

Toyota Corolla Cross: Lost Communication with ECM/PCM "A" (ch5) Missing Message (U115C87)

Toyota Corolla Cross (2022-2025) Service Manual / Engine & Hybrid System / M20a-fks (engine Control) / Sfi System / Lost Communication with ECM/PCM "A" (ch5) Missing Message (U115C87)

DESCRIPTION

The ECM and skid control ECU (brake actuator assembly) send and receive signals via CAN communication.

If a communication error occurs between the ECM and skid control ECU (brake actuator assembly), the ECM stores this DTC.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Note

U115C87

Lost Communication with ECM/PCM "A" (ch5) Missing Message

There is no communication between the ECM and skid control ECU (brake actuator assembly) (1 trip detection logic).
  • CAN communication system
  • Skid control ECU (brake actuator assembly)
  • ECM

Does not come on
  • SAE Code: U115C
  • DTC for Mexico Models: Applies

CONFIRMATION DRIVING PATTERN

  1. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
  2. Turn the ignition switch off and wait for at least 30 seconds.
  3. Turn the ignition switch to ON.
  4. Wait 2 seconds or more.
  5. Enter the following menus: Powertrain / Engine / Trouble Codes.
  6. Read the pending DTCs.

    HINT:

    • If a pending DTC is output, the system is malfunctioning.
    • If a pending DTC is not output, perform the following procedure.
  7. Enter the following menus: Powertrain / Engine / Utility / All Readiness.
  8. Input the DTC: U115C87.
  9. Check the DTC judgment result.

    HINT:

    • If the judgment result shows NORMAL, the system is normal.
    • If the judgment result shows ABNORMAL, the system is malfunctioning.

PROCEDURE

1.

GO TO CAN COMMUNICATION SYSTEM

(a) Refer to the CAN Communication System.

Click here

NEXT

END

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