Inspection Procedure
1: The rear display unit does not display at all.
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Whenever the rear display
unit is replaced, ensure that the communication circuit is normal.
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COMMENTS ON TROUBLE SYMPTOM
The cause is probably a faulty rear display unit power supply circuit system.
PROBABLE CAUSES
- Damaged wiring harness or connector.
- Malfunction of rear display unit.
DIAGNOSIS PROCEDURE
STEP 1. Voltage measurement at rear display unit connector
(ACC terminal).
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(1)Disconnect the connector, and measure at the wiring harness-side connector.
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(2)Turn the ignition switch to the ACC position.
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(3)Voltage between rear display unit connector (ACC terminal) and the body earth
OK: System voltage
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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 ACC line between rear display unit connector and ETACS-ECU 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 3. Voltage measurement at rear display unit connector (+B
terminal).
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(1)Disconnect the connector, and measure at the rear display unit side connector.
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(2)Voltage between rear display unit connector (+B terminal) and the body
earth.
OK: System voltage
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Q.
Is the check result normal?
Go to Step 5.
Go to Step 4.
STEP 4. Check of short to power supply, short to earth, and open circuit
in +B line between rear display unit connector and ETACS-ECU 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 5. Resistance measurement at rear display unit connector (GND
terminal).
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(1)Disconnect the connector, and measure at the wiring harness side.
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(2)Measure the resistance between rear display unit connector (GND terminal) and the
body earth.
OK: Continuity exists (2 Ω or less)
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Q.
Is the check result normal?
Go to Step 7.
Go to Step 6.
STEP 6. Check of open circuit in GND line between rear display unit
connector and earth joint 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 7. Retest the system.
Check if the rear display unit displays normally.
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 rear display unit (Refer to ).