Inspection Procedure 2: The System cannot be Activated or Deactivated Even When The Sonar Cancel Switch is Pressed.


caution
  • Whenever the ECU is replaced, ensure that the input signal circuit is normal.
  • When the illuminated licence plate is installed, the sensors may not operate because of noise from the plate. (When the ultrasonic noise is received, the bass toned buzzer sound continuously. When the ultrasonic noise stops, the normal operation will be resumed immediately.)










COMMENTS ON TROUBLE SYMPTOM
When the system cannot be activated or deactivated even if sonar cancel switch is pressed, the wiring harness, connectors, sonar cancel switch, or corner sensor-ECU may be defective.

PROBABLE CAUSES

  • Damaged harness wires and connectors
  • Malfunction of sonar cancel switch
  • Malfunction of corner sensor-ECU

DIAGNOSIS PROCEDURE

STEP 1. Connector check: D-27 Sonar cancel switch connector.

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

STEP 2. Inspection of sonar cancel switch
Inspect the sonar cancel switch for normal operation. Refer to .

Q. Is the check result normal?
Go to Step 3.
Replace the sonar cancel switch.

STEP 3. Resistance measurement at D-27 sonar cancel switch connector in order to the earth circuit to the sonar switch.
(1)Disconnect D-27 sonar cancel switch connector, and measure at the wiring harness side.
(2)Measure the resistance between terminal No. 4 and earth.
OK: Continuity exists (2 Ω or less)

Q. Is the check result normal?
Go to Step 5.
Go to Step 4.

STEP 4. Check the wiring harness between D-27 sonar cancel switch connector (terminal No. 4) and earth.

  • Check the earth wires for open circuit.

Q. Is the check result normal?
Retest the system.
Repair the wiring harness.

STEP 5. Connector check: D-16 Corner sensor-ECU connector.

Q. Is the check result normal?
Go to Step 6.
Repair the defective connector.

STEP 6. Check the wiring harness between D-27 sonar cancel switch connector (terminal No. 3) and D-16 corner sensor-ECU connector (terminal No. 13).

  • Check the communication lines for open circuit and short circuit.

Q. Is the check result normal?
Replace the corner sensor-ECU.
Repair the wiring harness.