Inspection Procedure 1: No Navigation Screen is Displayed.


caution Before replacing the ECU, ensure that the power supply circuit, the earth circuit and the communication circuit are normal.










DIAGNOSIS PROCEDURE

STEP 1. Connector check: C-11 audio visual navigation unit connector

Q. Is the check result normal?
Go to Step 2.
Repair or replace the damaged component(s).

STEP 2. Resistance measurement at C-10 audio visual navigation unit connector.
(1)Disconnect C-10 audio visual navigation unit connector, and measure the resistance available at the wiring harness side of the connector.
(2)Check the continuity between terminal 25 and body earth.
OK: Continuity exists (2 ohms or less)

Q. Is the check result normal?
Go to Step 4.
Go to Step 3.

STEP 3. Check the wiring harness between C-10 audio visual navigation unit connector terminal No.25 and body earth.

  • Check the earth wires for open circuit.

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 wiring harness.

STEP 4. Check the wiring harness between C-11 audio visual navigation unit connector terminal No.17 and fusible link (34).
note Prior to the wiring harness inspection, check intermediate connector C-19 and ETACS-ECU connectors C-307 and C-317, and repair if necessary.

  • Check the power supply lines (battery supply) for open circuit.

Q. Is the check result normal?
Go to Step 5.
Repair the wiring harness.

STEP 5. Connector check: C-10 audio visual navigation unit connector

Q. Is the check result normal?
Go to Step 6.
Repair or replace the damaged component(s).

STEP 6. Check the wiring harness between C-10 audio visual navigation unit connector terminal No.21 and fusible link (34).
note Prior to the wiring harness inspection, check intermediate connector C-21 and ETACS-ECU connectors C-307 and C-317, and repair if necessary.

  • Check the power supply lines (battery supply) for open circuit.

Q. Is the check result normal?
Go to Step 7.
Repair the wiring harness.

STEP 7. Retest the system
Check if the audio visual navigation unit power is turned ON.

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 audio visual navigation unit.