Diagnosis Procedure

Regarding Wiring Diagram information, refer to "WIRING DIAGRAM " (Bose Audio w/Navi w/o Surround) or "WIRING DIAGRAM " (Bose Audio w/Navi and Surround).

1. CHECK MIC IN SIGNAL CIRCUIT AND MIC VCC CIRCUIT CONTINUITY 
   1. Turn ignition switch OFF.
   2. Disconnect TCU connector M47 and microphone connector.
   3. Check continuity between TCU connector M47 and microphone connector R109.

      TCU		Microphone		Continuity
      Connector	Terminal	Connector	Terminal
      M47	18	R109	1	Yes
      	19		4
      	20		3

   4. Check the continuity between TCU connector M47 and ground.

      TCU		Ground	Continuity
      Connector	Terminal
      M47	18	-	No
      	19

      Is the inspection result normal? 

      YES: GO TO 2.

      NO: Repair or replace harness or connectors.

2. CHECK MIC VCC VOLTAGE 
   1. Connect TCU connector M47 and microphone connector.
   2. Turn ignition switch ON.
   3. Check voltage between terminals of TCU connector M47.

      TCU connector M47		Voltage (Approx.)
      (+)	(-)
      Terminal	Terminal
      18	20	5.0 V

      Is the inspection result normal? 

      YES: GO TO 3.

      NO: Replace TCU. Refer to "REMOVAL AND INSTALLATION ".

3. CHECK MIC IN SIGNAL 

   Check signal between terminals of TCU connector M47.

   TCU connector M47		Condition	Reference value
   (+)	(-)
   Terminal	Terminal
   19	20	Speak into microphone.

   Is the inspection result normal? 

   YES: Replace TCU. Refer to "REMOVAL AND INSTALLATION ".

   NO: Replace microphone. Refer to "REMOVAL AND INSTALLATION ".