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


If obstacle is not detected even when the selector lever is shifted to "R" (reverse) position, the wiring harness, connectors, inhibitor switch, or corner sensor/back sensor-ECU may be defective. In addition, obstacle is not detected when the ultrasonic noise is received.
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



DIAGNOSIS PROCEDURE


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


Use the M.U.T.-III to diagnose the CAN bus lines.

Q. Is the check result normal?

Go to Step 2.

Repair the CAN bus line (Refer to GROUP 54C - Troubleshooting - CAN Bus Diagnosis Chart ).

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


Check if the diagnosis code is set to the ETACS-ECU.

Q. Is the check result normal?

Troubleshoot the ETACS-ECU (Refer to GROUP 54A - ETACS - Diagnosis Code Chart ).

Go to Step 3

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)?

Move away or remove things that interfere with the communication (things that generate radio waves such as magnets and a air-cleaning device that has a power plug) near the reversing sensor (corner sensor/back sensor).

Go to Step 4

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?

Go to Step 10

Go to Step 5

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?

Go to Step 6

Repair the connector(s) or wiring harness.

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?

Go to Step 9

Go to Step 7

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


Check the input signal from the ignition switch (IG1) in the ETACS-ECU.

Item No.
 Item name
 Normal condition
Item 254
 IG voltage
 System voltage
OK: Normal condition is displayed.

Q. Is the check result normal?

Go to Step 8.

NO : Troubleshoot the ETACS-ECU. Refer to GROUP 54A - ETACS - Inspection Procedure 2 "The ignition switch (IG1) signal is not received" .

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?

The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction ).

Repair the connector(s) or wiring harness.

STEP 9. Check the inhibitor switch.


Check the continuity of the inhibitor switch (Refer to GROUP 23A - On-vehicle Service - Inhibitor Switch Continuity Check ).

Q. Is the check result normal?

The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction ).

Replace the inhibitor switch.

STEP 10. Retest the system


Check if an obstacle is detected when the selector lever is shifted to the "R" (Reverse) position.

Q. Is the check result normal?

The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction ).

Replace the corner sensor/back sensor-ECU.