Radio Receiver 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 the mode 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. Select the component shown by the sub-code.

   HINT: 

   The satellite radio tuner is built into the radio receiver assembly. If there is a problem between the satellite radio tuner and radio receiver assembly, replace the radio receiver assembly.

   COMPONENT TABLE
   
   

   Component	Proceed to
   Except satellite radio tuner	A
   Satellite radio tuner (1F1)	B

B → See step   7 

A: 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
   Multi-media interface ECU (388)	Multi-media interface ECU power source circuit. Refer to Multi-media Interface ECU 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   7 

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 following AVC-LAN wiring diagram, check the AVC-LAN circuit between the radio receiver assembly and the component shown by the sub-code.
   1. Disconnect all connectors between the radio receiver assembly and the component shown by the sub-code.
   2. Check for an open or short in the AVC-LAN circuit between the radio receiver assembly 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