Power Supply and Ground Circuit Check [Microphone]

Power Supply and Ground Circuit Check [Microphone]

Regarding Wiring Diagram information, refer to [Premium Audio System: Wiring Diagram [Crew Cab] Premium Audio System [Crew Cab] ].

1. CHECK POWER SUPPLY CIRCUIT (MICROPHONE SIDE)

1 Turn ignition switch ON.
2 Check voltage between microphone harness connector R8 terminal 4 and ground.











Is approximately 5 V present?
YES
GO TO 3
NO
GO TO 2

2. CHECK POWER SUPPLY CIRCUIT (CONTINUITY)

1 Turn ignition switch OFF.





2 Disconnect microphone and Bluetooth control unit harness connectors.
3 Check continuity between microphone harness connector R8 (A) terminal 4 and Bluetooth control unit harness connector B141 (B) terminal 29.






4 Check continuity between microphone harness connector R8 (A) terminal 4 and ground.






Are the continuity test results as specified?
YES
Replace the Bluetooth control unit. Refer to [Bluetooth Control Unit: Removal and Installation] Premium Audio (Crew Cab).
NO
Repair or replace harness or connector.

3. CHECK GROUND CIRCUIT

1 Turn ignition switch OFF.





2 Disconnect microphone harness connector R8 and Bluetooth control unit harness connector B141.
3 Check continuity between microphone harness connector R8 (A) terminal 2 and Bluetooth control unit harness connector B141 (B) terminal 8.






Does continuity exist?
YES
Inspection End.
NO
Repair or replace harness or connector.