Code No. P1AAA: ETACS Signal Time-out




TROUBLE JUDGEMENT


Check Condition
  • Power supply mode of electric motor switch: ON
Judgement Criterion
  • The signal sent by the ETACS-ECU through the CAN cannot be received.

FAIL-SAFE AND BACKUP FUNCTION



  • Not available

PROBABLE CAUSES



  • Failed harness and connector
  • The ETACS-ECU is failed.
  • The PHEV-ECU is failed.
  • The BMU is failed.

DIAGNOSIS PROCEDURE


STEP 1. M.U.T.-III CAN bus diagnosis



  • Using M.U.T.-III, perform CAN bus line diagnosis.

Q. Is the check result normal?

Go to Step 2.
Repair CAN bus line (Refer to GROUP 54C - Troubleshooting - CAN Bus Diagnostics Table ). After repairing CAN bus line, go to Step 7.

STEP 2. M.U.T.-III other system diagnosis code.



  • Confirm whether the diagnosis codes are stored in ETACS-ECU.

Q. Is diagnosis code of ETACS-ECU system stored?

Check ETACS-ECU system (Refer to GROUP 54A - ETACS - Diagnosis Code Chart ).
Go to Step 3.

STEP 3. M.U.T.-III diagnosis code



  • Check that the other ECU performing CAN communication with ETACS-ECU stores diagnosis code No. U0141 (Refer to GROUP 54C - CAN-Related Diagnosis Code Table )

Q. Is any other diagnosis code than U0141 stored?

Go to Step 4.
Go to Step 5.

STEP 4. M.U.T.-III other system diagnosis code.



  • Check that the other ECU performing CAN communication with ETACS-ECU stores diagnosis code No. U1109 (Refer to GROUP 54C - CAN-Related Diagnosis Code Table )

Q. Is the diagnosis code stored?

Go to Step 5.
Go to Step 7.

STEP 5. M.U.T.-III diagnosis code


Reconfirm whether the diagnosis codes are stored in BMU.

  1. Erase the stored diagnosis codes.
  2. Without depressing the brake pedal, operate the electric motor switch with the power supply mode of the electric motor switch OFF to turn ON the power supply mode of the electric motor switch.
  3. Confirm whether the diagnosis codes are stored.

Q. Is the diagnosis code stored?

Replace the ETACS-ECU. Then go to Step 6.
Intermittent malfunction in CAN bus line between BMU and ETACS-ECU (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).

STEP 6. M.U.T.-III diagnosis code


Reconfirm whether the diagnosis codes are stored in BMU.

  1. Erase the stored diagnosis codes.
  2. Without depressing the brake pedal, operate the electric motor switch with the power supply mode of the electric motor switch OFF to turn ON the power supply mode of the electric motor switch.
  3. Confirm whether the diagnosis codes are stored.

Q. Is the diagnosis code stored?

Replace the BMU. Then go to Step 7.
Intermittent malfunction in CAN bus line between BMU and ETACS-ECU (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).

STEP 7. M.U.T.-III diagnosis code


Reconfirm whether the diagnosis codes are stored in BMU.

  1. Erase the stored diagnosis codes.
  2. Without depressing the brake pedal, operate the electric motor switch with the power supply mode of the electric motor switch OFF to turn ON the power supply mode of the electric motor switch.
  3. Confirm whether the diagnosis codes are stored.

Q. Is the diagnosis code stored?

Go to Step 1.
Check end.