Pinpoint Test A: The Audio Unit Is Inoperative/Does Not Operate Correctly

Information and Entertainment System

Pinpoint Tests

Pinpoint Test A: The Audio Unit Is Inoperative/Does Not Operate Correctly

Refer to Wiring Diagram Set 130, Audio System for schematic and connector information. Diagrams By Number

Normal Operation

The audio unit receives voltage with the key in RUN or ACC. With the key in RUN or ACC and the audio unit on, all functions are operational.

This pinpoint test is intended to diagnose the following:

- Fuse
- Wiring, terminals or connectors
- Audio unit



PINPOINT TEST A: THE AUDIO UNIT IS INOPERATIVE/DOES NOT OPERATE CORRECTLY

NOTICE: For the CD6 audio unit, the audio unit must be placed in shipment mode before removal. Refer to Audio Unit Shipment Mode Audio Unit Shipment Mode. Failure to follow this instruction may result in damage to the audio unit.

NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

NOTE: Failure to disconnect the battery when instructed will result in false resistance readings. Refer to Battery.

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A1 CHECK THE OPERATION OF THE AUDIO UNIT


- Ignition ON.
- Turn the audio unit on.
- Is the audio unit display illuminated?

Yes
GO to A2.

No
GO to A3.

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A2 CHECK FOR SOUND COMING FROM THE SPEAKERS


- Verify that sound is coming from the speakers.
- Is there sound coming from the speakers?

Yes
GO to A3.

No
GO to Pinpoint Test C. Pinpoint Test C: Poor Quality/Distorted/No Sound From One Or More Speakers (Not All Speakers)

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A3 CHECK THE AUDIO UNIT POWER SUPPLY


- Ignition OFF.
- Disconnect: Audio Unit C290a.
- Ignition ON.
- Measure the voltage between the audio unit C290a-9, circuit SBP24 (VT/RD), harness side and ground; and between the audio unit C290a-10, circuit CBP06 (WH/BU), harness side and ground.




- Are the voltages greater than 10 volts?

Yes
GO to A4.

No
VERIFY the Smart Junction Box (SJB) fuse 6 (10A) or fuse 24 (20A) is OK. If OK, REPAIR the circuit in question. TEST the system for normal operation. If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short. Diagrams By Number

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A4 CHECK THE AUDIO UNIT GROUND CIRCUIT FOR CONTINUITY


- Ignition OFF.
- Disconnect: Negative Battery Cable.
- Measure the resistance between the audio unit C290a-11, circuit GD103 (BK/BU), harness side and ground; and between the audio unit C290a-16, circuit GD103 (BK/BU), harness side and ground.




- Are the resistances less than 5 ohms?

Yes
INSTALL a new audio unit. REFER to Audio Unit Audio Unit. TEST the system for normal operation.

No
REPAIR the circuit in question. TEST the system for normal operation.

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