Multi-media Interface ECU Communication Error: Procedure

1. Enter diagnostic mode.
   Fig 1: Service Check Mode Flow Chart - Diagnostic Mode (Example)

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2. Press preset switch "2" to change to "Detailed Information Mode".
3. Identify the component shown by the sub-code.

   HINT: 

   • The sub-code "P190" shown in the above example indicates the radio receiver assembly.
   • For details of the DTC display, refer to DTC Check/Clear. Refer to DTC CHECK / CLEAR .

NEXT: Go to next step 

1. Inspect the power source circuit of the component shown by the sub-code.

   If the power source circuit is operating normally, proceed to the next step.

   COMPONENT TABLE
   
   

   Component	Proceed to
   Radio receiver assembly (190)	Radio receiver power source circuit. Refer to Radio Receiver Power Source Circuit
   Satellite radio tuner (1F1)	Radio receiver power source circuit. Refer to Radio Receiver Power Source Circuit

NEXT: Go to next step 

1. Disconnect the radio receiver assembly connectors.
   Fig 2: Inspecting Radio Receiver E79 Connector Terminals

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2. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   E79-9 (TXM+) - E79-10 (TXM-)	Always	60 to 80 Ω

   TEXT IN ILLUSTRATION
   
   

   *a	Component without harness connected (Radio Receiver Assembly)

NG → See step   6 

OK: Go to next step 

HINT: 

• Start the check from the circuit that is near the component shown by the sub-code first.
• For details of the connectors, refer to Terminals of ECU. Refer to TERMINALS OF ECU .

1. Referring to the AVC-LAN wiring diagram below, check the AVC-LAN circuit between the multi-media interface ECU and the component shown by the sub-code.
   1. Disconnect all connectors between the multi-media interface ECU and the component shown by the sub-code.
   2. Check for an open or short in the AVC-LAN circuit between the multi-media interface ECU and the component shown by the sub-code.

      OK

      There is no open or short circuit.

      Fig 3: AVC-LAN Wiring Diagram

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NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Replace the component shown by the sub-code with a known good one and check if the same problem occurs again.

   OK

   Malfunction disappears.

NG → See step   7 

OK → END