Inspection Procedure 2: Brake Warning Lamp Stays ON with the Parking Brake Lever Released.





















OPERATION


When the parking brake switch is turned ON, the combination meter terminal No. 4 is earthed, and the brake warning lamp illuminates.

COMMENTS ON TROUBLE SYMPTOM


This may be caused by ground fault in the parking brake switch circuit.

PROBABLE CAUSES



  • Low brake fluid level
  • Damaged wiring harness and connectors
  • Parking brake switch malfunction
  • Combination meter malfunction
  • Malfunction of ETACS-ECU

DIAGNOSIS PROCEDURE


STEP 1. Brake fluid level check


Q. Is the check result normal?

Go to Step 2.
Add brake fluid to the specified level.

STEP 2. Brake fluid level switch check


Refer to GROUP 35A - On-vehicle Service .

Q. Is the check result normal?

Go to Step 3.
Replace the reservoir assembly and master cylinder assembly.

STEP 3. Voltage measurement at C-312 ETACS-ECU connector



  • Measure the voltage between the terminal No. 1 and the body earth.
OK: Approx. 5 V

Q. Is the check result normal?

Go to Step 4.
Replace ETACS-ECU.

STEP 4. Connector check: C-312 ETACS-ECU connector, A-10 brake fluid level switch connector


Q. Is the check result normal?

Go to Step 5.
Repair the defective connector.

STEP 5. Check the wiring harness between the C-312 ETACS-ECU connector terminal No. 1 and the A-10 brake fluid level switch connector terminal No. 1.


Q. Is the check result normal?

Go to Step 6.
Check the wiring harness between the C-312 ETACS-ECU connector terminal No. 1 and the A-10 brake fluid level switch connector terminal No. 1.

STEP 6. Parking brake lever stroke check


Refer to GROUP 36 - On-vehicle Service .

Q. Is the check result normal?

Go to Step 7.
Adjust the parking brake lever stroke, and then go to Step 10.

STEP 7. Parking brake switch check


Refer to GROUP 36 - On-vehicle Service .

Q. Is the check result normal?

Go to Step 8.
Replace the parking brake switch.

STEP 8. Voltage measurement at the C-03 combination meter connector



  • Measure the voltage between terminal No. 4 and body earth.
OK: Approx. 5 V

Q. Is the check result normal?

Go to Step 9.
Replace the combination meter assembly, and then go to Step 10.

STEP 9. Connector check: C-03 Combination meter connector, C-22 intermediate connector, D-124 parking brake switch connector


Q. Is the check result normal?

Repair the wiring harness between the C-03 combination meter connector terminal No. 4 and the D-124 parking brake switch connector.
Repair the defective connector.

STEP 10. Retest the system.


Q. Does the brake warning lamp turn ON and OFF normally according to the parking brake lever operation?

The procedure is complete.
Return to Step 1.