Code No. U1210: Brake Lamp Switch Status Error




TROUBLE JUDGMENT


Check Conditions
  • 2 seconds later after the ignition switch has been in "ON" position or the engine has started up.
  • The battery voltage is more than 9 V and is less than 16 V.
  • Neither of the following diagnosis codes is set.

  1. Code No. U0121: ASC-ECU Time-out
  2. Code No. U0141: ETACS-ECU Time-out
Judgement Criterion
  • The brake lamp switch is "OFF" when the brake master cylinder hydraulic pressure is 1 MPa or more

COMMENTS ON TROUBLE SYMPTOM


Current malfunction
  • The failure is possibly caused by malfunction of the ASC-ECU signal, by malfunction in the ASC-ECU, of the ETACS-ECU signal, of the brake lamp switch (stuck to "OFF"), in the AS&G-ECU.
Past malfunction
  • Proceed with troubleshooting focusing on malfunction of the ASC-ECU signal and malfunction of the brake lamp switch system. For diagnosis procedure, refer to cope with past malfunctions (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions).
FAIL-SAFE AND BACKUP FUNCTION
  • In the normal operation, the auto stop is prohibited.
  • If the malfunction is detected during the auto stop, the auto start is prohibited.

PROBABLE CAUSES



  • Failed brake master cylinder hydraulic pressure signal that is entered in the AS&G-ECU from the ASC-ECU via CAN communication
  • Failed brake lamp switch signal that is entered in the AS&G-ECU from the ETACS-ECU via CAN communication
  • Failed ASC-ECU
  • Failed AS&G-ECU

DIAGNOSIS PROCEDURE


STEP 1. M.U.T.-III diagnosis code for other systems


Confirm the diagnosis code is set from the ASC-ECU.

Q. Is the check result normal?

Perform troubleshooting of the ASC-ECU (Refer to GROUP 35C - Troubleshooting - Diagnosis Code Chart ).
Go to Step 2.

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



  • Item 30: Brake lamp switch
OK: ON (depress the brake pedal), OFF (release the brake pedal)

Q. Is the diagnosis code set?

Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions).
Go to Step 3.

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



  • Check the ETACS-ECU service data (Refer to GROUP 54A - ETACS - Data List Reference Table).
  • Item 290: Stop lamp switch
OK: ON (depress the brake pedal), OFF (release the brake pedal)

Q. Is the diagnosis code set?

Go to Step 5.
Go to Step 4.

STEP 4. Check stop lamp switch


Check stop lamp switch (Refer to GROUP 35A - Brake Pedal - Stop Lamp Switch Check).

Q. Is the diagnosis code set?

Check if the circuits related to the stop lamp switch are normal.
Replace the AS&G OFF switch.

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



  • Reconfirmation of diagnosis code.
Confirm again the diagnosis code is set from the AS&G-ECU.

  1. Erase the set diagnosis code.
  2. Ignition switch: "LOCK" (OFF) → "ON"
  3. Confirm whether the diagnosis code is set.

Q. Is the diagnosis code set?

Replace the AS&G-ECU.
Check end.