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Pinpoint Test E: Poor Quality/Distorted/No Sound From One Or More Speakers (Not All Speakers) - Sony(R) Sound




Information and Entertainment System

Pinpoint Test E: Poor Quality/Distorted/No Sound From One Or More Speakers (Not All Speakers) - Sony(R) Sound

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

Normal Operation

The Audio Control Module (ACM) directs audio signals to the audio Digital Signal Processing (DSP) module in the form of an AC voltage. The audio DSP (Digital Signal Processing) module boosts the audio signals and sends them to the speakers and to the audio amplifier, which powers the subwoofer speakers. The ACM (Audio Control Module) and audio DSP (Digital Signal Processing) module provide internal circuit protection for shorts to ground or shorts to voltage.

A short to ground or short to voltage in the circuitry to one of the speakers may cause multiple speakers to lose sound due to the built-in overload protection feature. In this case, a speaker fault DTC sets, and this pinpoint test should be followed to isolate the damaged circuit.

The speaker walk test can be used to isolate a concern with a particular speaker. This can reduce the diagnostic steps necessary to isolate the concern. To carry out the speaker walk test, refer to Audio Control Module (ACM) Self-Diagnostic Mode Service and Repair.

To enable the audio DSP (Digital Signal Processing) module, the ACM (Audio Control Module) sends voltage through the enable/clip circuit. The circuit acts as both an output (to enable the amplifier) and an input (to detect an overload condition). The voltage sent by the ACM (Audio Control Module) passes through a variable resistor in the audio DSP (Digital Signal Processing) module, then to ground. As the amplifier reaches maximum output, the resistance in the variable resistor decreases. This decreases the voltage drop, resulting in the ACM (Audio Control Module) detecting a higher voltage on the enable/clip circuit. When the voltage reaches the clip threshold, the ACM (Audio Control Module) clips the audio output signal to the amplifier (heard as distortion), in order to prevent damage to the amplifier and speakers.

The enable/clip status is based on the following voltages, as detected by the ACM (Audio Control Module) :

- Less than 0.4 volt: amplifier disabled

- Between 3.8 and 6.7 volts (nominal): amplifier enabled

- Greater than 8.5 volts: amplifier clipped

An open in the enable/clip circuit causes the speakers to produce no sound because the enable signal does not reach the audio DSP (Digital Signal Processing) module. A short to ground or short to voltage can cause severe distortion to be heard in the speakers.

The audio DSP (Digital Signal Processing) module controls the enable/clip circuit to the audio amplifier. This circuit functions the same as the enable/clip circuit from the ACM (Audio Control Module) to the audio DSP (Digital Signal Processing) module.

The ACM (Audio Control Module) sends the audio signals to the audio DSP (Digital Signal Processing) module in the following banks:





For vehicles with navigation, it is important to note that if the navigation voice guidance setting is set too low, it may appear that the front speakers intermittently produce no sound. Make sure the voice guidance setting is set high enough to hear the voice guidance commands before addressing a concern with the front speakers.

ACM (Audio Control Module) DTCs






Audio DSP (Digital Signal Processing) Module DTCs






This pinpoint test is intended to diagnose the following:

- Fuse

- Wiring, terminals or connectors

- Speaker

- Audio DSP (Digital Signal Processing) module

- Audio amplifier

- ACM (Audio Control Module)

PINPOINT TEST E : POOR QUALITY/DISTORTED/NO SOUND FROM ONE OR MORE SPEAKERS (NOT ALL SPEAKERS) - SONY(R) SOUND

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.

E1 DETERMINE THE INOPERATIVE SPEAKER(S)

- Carry out the speaker walk test. Refer to Audio Control Module (ACM) Self-Diagnostic Mode Service and Repair.

Is the concern only with the subwoofer speaker(s)?

Yes
GO to E2.

No
GO to E14.

E2 DETERMINE THE INOPERATIVE SUBWOOFER

- Operate the audio system in radio tuner (AM/FM) mode and observe the subwoofer operation.

Do both of the subwoofers have a concern?

Yes
GO to E3.

No
GO to E11.

E3 CHECK THE AUDIO AMPLIFIER VOLTAGE SUPPLY

- Ignition OFF.

- Disconnect: Audio Amplifier C4208A.

- Measure the voltage between the audio amplifier C4208A-5, circuit SBP38 (BN/RD), harness side and ground; and between the audio amplifier C4208A-4, circuit SBP38 (BN/RD), harness side and ground.





Are the voltages greater than 10 volts?

Yes
GO to E4.

No
VERIFY the Smart Junction Box (SJB) fuse 38 (20A) is OK. If OK, REPAIR the circuit in question. CLEAR any DTCs present. 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

E4 CHECK THE AUDIO AMPLIFIER GROUND CIRCUIT FOR CONTINUITY

- Disconnect: Negative Battery Cable.

- Measure the resistance between the audio amplifier C4208A-2, circuit GD149 (BK/GY), harness side and ground.





Is the resistance less than 5 ohms?

Yes
GO to E5.

No
REPAIR the circuit. CLEAR any DTCs present. TEST the system for normal operation.

E5 CHECK THE AUDIO AMPLIFIER ENABLE CIRCUIT FOR CORRECT VOLTAGE

- Connect: Negative Battery Cable.

- Operate the audio system in radio tuner (AM/FM) mode.

- Measure the voltage between the audio amplifier C4208A-1, circuit SME23 (VT/RD), harness side and ground.





Is the voltage between 3.8 and 6.7 volts?

Yes
GO to E8.

No
GO to E6.

E6 CHECK THE AUDIO AMPLIFIER ENABLE CIRCUIT FOR A SHORT TO VOLTAGE

- Ignition OFF.

- Disconnect: Audio DSP (Digital Signal Processing) Module C4326C.

- Ignition ON.

- Measure the voltage between the audio amplifier C4208A-1, circuit SME23 (VT/RD), harness side and ground.





Is any voltage present?

Yes
REPAIR the circuit. TEST the system for normal operation.

No
GO to E7.

E7 CHECK THE AUDIO AMPLIFIER ENABLE CIRCUIT FOR AN OPEN OR SHORT TO GROUND

- Ignition OFF.

- Measure the resistance between the audio amplifier C4208A-1, circuit SME23 (VT/RD), harness side and the audio DSP (Digital Signal Processing) module C4326C-1, circuit SME23 (VT/RD), harness side and ground; and between the audio amplifier C4208A-1, circuit SME23 (VT/RD), harness side and ground.





Is the resistance less than 5 ohms between the audio amplifier and the audio DSP (Digital Signal Processing) module, and greater than 10,000 ohms between the audio amplifier and ground?

Yes
GO to E23.

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

E8 CHECK THE AUDIO SIGNAL TO THE AUDIO AMPLIFIER

- Operate the audio system in radio tuner (AM/FM) mode.

- Measure the AC voltage between the audio amplifier C4208A-7, circuit VME22 (VT/GN), harness side and the audio amplifier C4208A-8, circuit RME22 (GN/WH), harness side.





Is a fluctuating AC voltage present?

Yes
INSTALL a new audio amplifier. REFER to Audio Amplifier . CLEAR any DTCs present. TEST the system for normal operation.

No
GO to E9.

E9 CHECK THE AUDIO CIRCUITS TO THE AUDIO AMPLIFIER FOR A SHORT TO VOLTAGE

- Ignition OFF.

- Measure the voltage between the audio amplifier C4208A-7, circuit VME22 (VT/GN), harness side and ground; and between the audio amplifier C4208A-8, circuit RME22 (GN/WH), harness side and ground.





Is any voltage present?

Yes
REPAIR the circuit in question. CLEAR any DTCs present. TEST the system for normal operation.

No
GO to E10.

E10 CHECK THE AUDIO CIRCUITS TO THE AUDIO AMPLIFIER FOR AN OPEN OR SHORT TO GROUND

- Measure the resistance between the audio amplifier, harness side and the audio DSP (Digital Signal Processing) module, harness side; and between the audio amplifier, harness side and ground as follows:









Is the resistance less than 5 ohms between the audio amplifier and the audio DSP (Digital Signal Processing) module, and greater than 10,000 ohms between the audio amplifier and ground?

Yes
GO to E21.

No
REPAIR the circuit in question. CLEAR any DTCs present. TEST the system for normal operation.

E11 CHECK THE AUDIO SIGNAL TO THE SUSPECT SUBWOOFER SPEAKER

- Ignition OFF.

- Disconnect: Suspect Subwoofer Speaker.

- Ignition ON.

- Operate the audio system in radio tuner (AM/FM) mode.

- Measure the AC voltage between the LH subwoofer speaker C3120-1, circuit VME01 (GN/VT), harness side and the LH subwoofer speaker C3120-2, circuit RME01 (GY), harness side; or between the RH subwoofer speaker C3121-1, circuit VME02 (VT), harness side and the RH subwoofer speaker C3121-2, circuit RME02 (YE), harness side.





Is a fluctuating AC voltage present?

Yes
INSTALL a new subwoofer speaker for the suspect speaker. REFER to Speaker - Subwoofer . TEST the system for normal operation.

No
GO to E12.

E12 CHECK THE AUDIO CIRCUITS TO THE SUSPECT SUBWOOFER SPEAKER FOR A SHORT TO VOLTAGE

- Ignition OFF.

- Disconnect: Audio Amplifier C4208B.

- Ignition ON.

- Measure the voltage between the suspect subwoofer speaker, harness side and ground as follows:









Is any voltage present?

Yes
REPAIR the circuit in question. TEST the system for normal operation.

No
GO to E13.

E13 CHECK THE AUDIO CIRCUITS TO THE SUSPECT SUBWOOFER SPEAKER FOR AN OPEN OR SHORT TO GROUND

- Ignition OFF.

- Measure the resistance between the suspect subwoofer speaker, harness side and the audio amplifier, harness side; and between the suspect subwoofer speaker, harness side and ground as follows:









Is the resistance less than 5 ohms between the suspect subwoofer speaker and the audio amplifier, and greater than 10,000 ohms between the suspect subwoofer speaker and ground?

Yes
INSTALL a new audio amplifier. REFER to Audio Amplifier . CLEAR any DTCs present. TEST the system for normal operation.

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

E14 CHECK FOR AN AUDIO SIGNAL TO THE SUSPECT SPEAKER

- Ignition OFF.

- Disconnect: Suspect Speaker.

- Operate the audio system in radio tuner (AM/FM) mode.

- Measure the AC voltage between the suspect speaker pins, harness side as follows:









Is a fluctuating AC voltage present?

Yes
INSTALL a new speaker for the suspect speaker. REFER to the appropriate removal and installation procedure. CLEAR any DTCs present. TEST the system for normal operation.

No
GO to E15.

E15 CHECK THE AUDIO DSP (Digital Signal Processing) MODULE VOLTAGE SUPPLY

- Ignition OFF.

- Disconnect: Audio DSP (Digital Signal Processing) Module C4326C.

- Measure the voltage between the audio DSP (Digital Signal Processing) module C4326C-5, circuit SBP19 (BU/RD), harness side and ground; and between the audio DSP (Digital Signal Processing) module C4326C-6, circuit SBP19 (BU/RD), harness side and ground.





Are the voltages greater than 10 volts?

Yes
GO to E16.

No
VERIFY the Smart Junction Box (SJB) fuse 19 (25A) 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

E16 CHECK THE AUDIO DSP (Digital Signal Processing) MODULE GROUND CIRCUITS FOR CONTINUITY

- Ignition OFF.

- Disconnect: Negative Battery Cable.

- Measure the resistance between the audio DSP (Digital Signal Processing) module C4326C-13, circuit GD149 (BK/GY), harness side and ground; and between the audio DSP (Digital Signal Processing) module C4326C-14, circuit GD149 (BK/GY), harness side and ground.





Are the resistances less than 5 ohms?

Yes
GO to E17.

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

E17 CHECK THE AUDIO SIGNALS TO THE AUDIO DSP (Digital Signal Processing) MODULE

- Connect: Audio DSP (Digital Signal Processing) Module C4326C.

- Disconnect: Audio DSP (Digital Signal Processing) Module C4326A.

- Operate the audio system in radio tuner (AM/FM) mode.

- Measure the AC voltage between the audio DSP (Digital Signal Processing) module pins, harness side as follows:









Is a fluctuating AC voltage present?

Yes
GO to E18.

No
GO to E20.

E18 CHECK THE SPEAKER CIRCUITS FOR A SHORT TO VOLTAGE

- Ignition OFF.

- Connect: Audio DSP (Digital Signal Processing) Module C4326A.

- Disconnect: Audio DSP (Digital Signal Processing) Module C4326B.

- Ignition ON.

- Measure the voltage between the suspect speaker, harness side and ground as follows:









Is any voltage present?

Yes
REPAIR the circuit in question. CLEAR any DTCs present. TEST the system for normal operation.

No
GO to E19.

E19 CHECK THE SPEAKER CIRCUITS FOR AN OPEN OR SHORT TO GROUND

- Ignition OFF.

- Measure the resistance between the suspect speaker, harness side and the audio DSP (Digital Signal Processing) module, harness side; and between the suspect speaker, harness side and ground as follows:









Are the resistances less than 5 ohms between the suspect speaker and the audio DSP (Digital Signal Processing) module, and greater than 10,000 ohms between the suspect speaker and ground?

Yes
GO to E23.

No
REPAIR the circuit in question. CLEAR any DTCs present. TEST the system for normal operation.

E20 CHECK THE AUDIO CIRCUITS TO THE AUDIO DSP (Digital Signal Processing) MODULE FOR A SHORT TO VOLTAGE

- Ignition OFF.

- Disconnect: ACM (Audio Control Module) C240A (Except Instrument Panel Speaker or Subwoofer Concern) or C240D (Instrument Panel Speaker or Subwoofer Concern).

- Ignition ON.

- Measure the voltage between the audio DSP (Digital Signal Processing) module pins, harness side and ground as follows:









Is any voltage present?

Yes
REPAIR the circuit in question. CLEAR any DTCs present. TEST the system for normal operation.

No
GO to E21.

E21 CHECK THE AUDIO CIRCUITS TO THE AUDIO DSP (Digital Signal Processing) MODULE FOR A SHORT TO GROUND

- Ignition OFF.

- Measure the resistance between the ACM (Audio Control Module), harness side, and the audio DSP (Digital Signal Processing) module, harness side; and between the ACM (Audio Control Module), harness side and ground as follows:









Are the resistances less than 5 ohms between the ACM (Audio Control Module) and the audio DSP (Digital Signal Processing) module, and greater than 10,000 ohms between the ACM (Audio Control Module) and ground?

Yes
GO to E22.

No
REPAIR the circuit in question. CLEAR any DTCs present. TEST the system for normal operation.

E22 CHECK FOR CORRECT ACM (Audio Control Module) OPERATION

- Connect: All Disconnected Connectors.

- Disconnect all the ACM (Audio Control Module) connectors.

- Check for:
- corrosion

- damaged pins

- pushed-out pins


- Connect all the ACM (Audio Control Module) connectors and make sure they seat correctly.

- Operate the system and determine if the concern is still present.

Is the concern still present?

Yes
INSTALL a new ACM (Audio Control Module). REFER to Audio Control Module (ACM) . TEST the system for normal operation.

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR any DTCs present.

E23 CHECK FOR CORRECT AUDIO DSP (Digital Signal Processing) MODULE OPERATION

- Connect: All Disconnected Connectors.

- Disconnect all the audio DSP (Digital Signal Processing) module connectors.

- Check for:
- corrosion

- damaged pins

- pushed-out pins


- Connect all the audio DSP (Digital Signal Processing) module connectors and make sure they seat correctly.

- Operate the system and determine if the concern is still present.

Is the concern still present?

Yes
INSTALL a new audio DSP (Digital Signal Processing) module. REFER to Audio Digital Signal Processing (DSP) Module . TEST the system for normal operation.

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR any DTCs present.