Inspection Procedure 6: Obstacle is not detected even when the selector lever is shifted to "R" (Reverse) position.



caution
  • Before replacing the ECU or sensor, ensure that the power supply circuit, the earth circuit and the communication circuit are 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



note If ultrasonic noise is received with the sensor, the corner sensor/bock sensor sounds the low toned buzzer continuously and turns off the system. When the ultrasonic noise is stopped, the sensor returns to normal.

PROBABLE CAUSES



  • Damaged harness wires and connectors
  • Malfunction of the inhibitor switch
  • Malfunction of corner sensor/back sensor-ECU

DIAGNOSIS PROCEDURE


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



Q. Is the check result normal?





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



Q. Is the check result normal?





STEP 3. Check the reversing sensor (corner sensor/back sensor) for interference.


Q. Is there anything that interferes with the communication (things that generate radio waves such as magnets and an air-cleaning device that has a power plug) near the reversing sensor (corner sensor/back sensor)?





STEP 4. Voltage measurement at ETACS-ECU connector (BLP1 terminal).


(1)Disconnect the connector, and measure at the wiring harness side.
(2)Turn the ignition switch to the "ON" position, and move the selector lever to the "R" position.
(3)Check the voltage between the ETACS-ECU connector (BLP1 terminal) and body earth.
OK: System voltage

Q. Is the check result normal?





STEP 5. Check of short to power supply, short to earth, and open circuit in BLP1 line between ETACS-ECU connector and inhibitor switch connector.


Q. Is the check result normal?





STEP 6. Voltage measurement at inhibitor switch connector (power supply terminal).


(1)Disconnect B-109 inhibitor switch connector, and measure at the wiring harness side.
(2)Turn the ignition switch to "ON" position.
(3)Check the voltage between the inhibitor switch connector (power supply terminal) and body earth.
OK: System voltage

Q. Is the check result normal?





STEP 7. M.U.T.-III other system service data




  • Turn the ignition switch to the ON position.
Item No.
Item name
Normal condition
Item 254
IG voltage
System voltage
OK: Normal condition is displayed.

Q. Is the check result normal?





STEP 8. Check of short to power supply, short to earth, and open circuit in power supply line between fusible link and inhibitor switch connector.


Q. Is the check result normal?





STEP 9. Check the inhibitor switch.



Q. Is the check result normal?





STEP 10. Retest the system



Q. Is the check result normal?