Inspection Procedure 26: Stop Lamp Switch System <Vehicles with Auto-cruise Control System>








OPERATION



FUNCTION



PROBABLE CAUSES



DIAGNOSIS PROCEDURE

STEP 1. Connector check: C-126 stop lamp switch connector

Q. Is the check result normal?
Go to Step 2 .
Repair or replace the connector.

STEP 2. Perform voltage measurement at C-126 stop lamp switch connector.

  • Disconnect connector, and measure at the harness side.
  • Ignition switch: ON
  • Voltage between terminal No. 3 and earth.
OK: System voltage

Q. Is the check result normal?
Go to Step 5 .
Go to Step 3 .

STEP 3. Connector check: B-06 engine-ECU connector

Q. Is the check result normal?
Go to Step 4 .
Repair.

STEP 4. Check harness between C-126 (terminal No. 3) stop lamp switch connector and B-06 (terminal No. 81) engine-ECU connector.

  • Check output line for open/short circuit.

Q. Is the check result normal?
Replace the engine-ECU.
Repair.

STEP 5. Perform resistance measurement at C-126 stop lamp switch connector.

  • Disconnect connector, and measure at the harness side.
  • Resistance between terminal No. 4 and earth.
OK: 2 Ω or less

Q. Is the check result normal?

Go to Step 6 .

    Check and repair harness between C-126 (terminal No. 4) stop lamp switch connector and body earth.

    • Check earthing line for open circuit and damage.

STEP 6. Check the stop lamp switch

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

Q. Is the check result normal?
Go to Step 7 .
Replace the stop lamp switch.

STEP 7. Check harness between C-126 (terminal No. 3) stop lamp switch connector and B-06 (terminal No. 81) engine-ECU connector.

  • Check output line for damage.

Q. Is the check result normal?
Go to Step 8 .
Repair.

STEP 8. Check the trouble symptoms.

Q. Does trouble symptom persist?

Replace the engine-ECU.
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).