Inspection Procedure
1: The reversing sensor system does not operate.
caution
Before replacing
the ECU or sensor, ensure that the power supply circuit, the earth circuit and the communication
circuit are normal.
When the ETACS-ECU of vehicles without KOS is replaced, the encrypted code of the ignition
key needs to be registered to the ETACS-ECU. (If the encrypted code is not registered, the engine
cannot be started. Register the encrypted code as described in Immobilizer System - How
to Register Key ID .)
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 the Reversing sensor system does not work at all even when the ignition switch is turned
"ON", the power supply system, corner sensor/back sensor-ECU or ETACS-ECU may have a problem.
PROBABLE CAUSES
Malfunction of corner sensor/back sensor-ECU
Malfunction of the ETACS-ECU
Damaged harness wires and connectors
DIAGNOSIS PROCEDURE
STEP 1. Voltage measurement at corner sensor/back sensor-ECU
connector (IG terminal).
(1)Disconnect the connector, and measure at the wiring harness side.
(2)Turn the ignition switch to the "ON" position.
(3)Check the voltage between the corner sensor/back sensor-ECU connector (IG terminal)
and body earth. OK: System voltage
Q.
Is the check result normal?
Go to Step 3.
Go to Step 2.
STEP 2. Check of short to power supply, short to earth, and open circuit
in IG line between ETACS-ECU connector and corner sensor/back sensor-ECU connector.
Q.
Is the check result normal?
Troubleshoot the ETACS-ECU. Refer to GROUP 54A - ETACS - Input
Signal Procedures - Inspection Procedure 2 "The ignition switch (IG1) signal is not
received" .
(1)Disconnect the connector, and measure at the wiring harness side.
(2)Measure the resistance between the corner sensor/back sensor-ECU connector (PGND terminal)
and body 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 of open circuit in PGND line between corner sensor/back
sensor-ECU connector and body earth.
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 5. Replace the corner sensor/back sensor-ECU temporarily, and
then check the trouble symptom.
Replace the corner sensor/back sensor-ECU temporarily, then check if the corner sensors operate.
.)
