Last Modified: 07-31-2024 6.11:8.1.0 Doc ID: RM100000001NG0L
Model Year Start: 2021 Model: Corolla Hatchback Prod Date Range: [04/2020 - 09/2022]
Title: M20A-FKS (ENGINE CONTROL): SFI SYSTEM: U012987; Lost Communication with Brake System Control Module Missing Message; 2021 - 2022 MY Corolla Corolla Hatchback [04/2020 - 09/2022]

DTC

U012987

Lost Communication with Brake System Control Module Missing Message

MONITOR 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

Memory

Note

U012987

Lost Communication with Brake System Control Module Missing Message

All of the following conditions are met for 2.2 seconds*1 or 2.4 seconds*2 or more (1 trip detection logic):

  • Ignition switch ON
  • Battery voltage is 10 V or higher
  • No communication between ECM and skid control ECU (brake actuator assembly)
  • CAN communication system
  • Skid control ECU (brake actuator assembly)
  • ECM

Does not come on

DTC stored
  • SAE Code: U0129
  • DTC for Mexico Models: Applies
  • *1: for Sedan models with manual transaxle
  • *2: except Sedan models with manual transaxle

MONITOR STRATEGY

Frequency of Operation

Continuous

CONFIRMATION DRIVING PATTERN

HINT:

  • After repair has been completed, clear the DTC and then check that the vehicle has returned to normal by performing the following All Readiness check procedure.

    Click here 2019 - 2022 MY Corolla Corolla Hatchback [06/2018 - 09/2022]; M20A-FKS (ENGINE CONTROL): SFI SYSTEM: DTC CHECK / CLEAR

  • When clearing the permanent DTCs, refer to the "CLEAR PERMANENT DTC" procedure.

    Click here 2019 - 2022 MY Corolla Corolla Hatchback [06/2018 - 09/2022]; M20A-FKS (ENGINE CONTROL): SFI SYSTEM: DTC CHECK / CLEAR

  1. Connect the Techstream to the DLC3.
  2. Turn the ignition switch to ON.
  3. Turn the Techstream on.
  4. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
  5. Turn the ignition switch off and wait for at least 30 seconds.
  6. Turn the ignition switch to ON [A].
  7. Turn the Techstream on.
  8. Wait 5 seconds or more.
  9. Enter the following menus: Powertrain / Engine / Trouble Codes [B].
  10. 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.
  11. Enter the following menus: Powertrain / Engine / Utility / All Readiness.
  12. Input the DTC: U012987.
  13. Check the DTC judgment result.

    Techstream Display

    Description

    NORMAL
    • DTC judgment completed
    • System normal

    ABNORMAL
    • DTC judgment completed
    • System abnormal

    INCOMPLETE
    • DTC judgment not completed
    • Perform driving pattern after confirming DTC enabling conditions

    HINT:

    • If the judgment result shows NORMAL, the system is normal.
    • If the judgment result shows ABNORMAL, the system is malfunctioning.
    • [A] to [B]: Normal judgment procedure.

      The normal judgment procedure is used to complete DTC judgment and also used when clearing permanent DTCs.

    • When clearing the permanent DTCs, do not disconnect the cable from the auxiliary battery terminal or attempt to clear the DTCs during this procedure, as doing so will clear the universal trip and normal judgment histories.

CAUTION / NOTICE / HINT

HINT:

Read freeze frame data using the Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.

PROCEDURE

1.

CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC U012987)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Enter the following menus: System Select / Health Check.

(e) Read the DTCs.

Result

Proceed to

DTC U012987 is output

A

DTC U012987 and other DTCs are output

B

HINT:

If any DTCs other than U012987 are output, troubleshoot those DTCs first.

A

GO TO CAN COMMUNICATION SYSTEM

B

GO TO DTC CHART