Pinpoint Test F: Poor Quality/Distorted/No Sound From One Or More Speakers (Not All Speakers) - THX(R) Sound
Information and Entertainment System
Pinpoint Test F: Poor Quality/Distorted/No Sound From One Or More Speakers (Not All Speakers) - THX(R) Sound
Refer to Wiring Diagram Set 130, Audio System/Navigation for schematic and connector information. [1][2]Diagrams By Number
Normal Operation
The Audio Control Module (ACM) directs the 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. The audio DSP (Digital Signal Processing) module provides internal circuit protection for shorts to ground or shorts to voltage.
A short to ground or short to voltage in the circuit to one of the speakers may cause multiple speakers to lose sound due to the built-in overload protection feature of the audio DSP (Digital Signal Processing) module. In this case, a speaker fault DTC sets, and this pinpoint test should be followed to isolate the damaged circuit.
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 also 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.
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.
This pinpoint test is intended to diagnose the following:
- Fuse
- Wiring, terminals or connectors
- Speaker
- Audio DSP (Digital Signal Processing) module
- ACM (Audio Control Module)
PINPOINT TEST F : POOR QUALITY/DISTORTED/NO SOUND FROM ONE OR MORE SPEAKERS (NOT ALL SPEAKERS) - THX(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.
F1 CHECK THE AUDIO SIGNALS 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:
Suspect Speaker Positive Meter Lead Negative Meter Lead LH subwoofer C3307-1 VME01 (GN/VT) C3307-2 RME01 (GY) LR door C702-1 VME09 (WH/GN) C702-2 RME09 (BN/YE) LF door C523-1 VME07 (WH) C523-2 RME07 (WH/BN) LH tweeter C569-1 VME08 (GN/OG) C569-2 RME08 (GY/OG) LH front imaging C2358-1 VME28 (BN/VT) C2358-4 RME28 (BN/GN) Center front imaging C2358-2 VME06 (GN) C2358-5 RME06 (GY/YE) RH front imaging C2358-3 VME29 (GN/WH) C2358-6 RME29 (BU/WH) RH tweeter C613-1 VME11 (VT/OG) C613-2 RME11 (YE/OG) RF door C612-1 VME10 (WH/VT) C612-2 RME10 (WH/OG) RR door C802-1 VME12 (BN/WH) C802-2 RME12 (BN/BU) RH subwoofer C3308-1 VME02 (VT) C3308-2 RME02 (YE) Rear center imaging C3306-1 VME30 (GN/BN) C3306-2 RME30 (VT/BN)
Is a fluctuating AC voltage present?
Yes
INSTALL a new speaker for the suspect speaker. REFER to the appropriate removal and install procedure. CLEAR any DTCs present. TEST the system for normal operation.
No
GO to F2.
F2 CHECK THE AUDIO SIGNALS TO THE AUDIO DSP (Digital Signal Processing) MODULE
- Ignition OFF.
- Disconnect: Audio DSP (Digital Signal Processing) Module C4235C.
- 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:
Suspect Speaker Positive Meter Lead Negative Meter Lead All LH speakers (without navigation), LF door or LF tweeter (with navigation) C4235C-7 VME07 (WH) C4235C-17 RME07 (WH/BN) All RH speakers (without navigation), RF door or RF tweeter (with navigation) C4235C-8 VME10 (WH/VT) C4235C-18 RME10 (WH/OG) LR door (with navigation) C4235C-4 VME09 (WH/GN) C4235C-14 RME09 (BN/YE) RR door (with navigation) C4235C-10 VME12 (BN/WH) C4235C-20 RME12 (BN/BU) Instrument panel or parcel shelf (with navigation) C4235C-9 VME51 (BN/BU) C4235C-19 RME51 (WH/BU) Subwoofer #1 or #2 C4235C-5 VME22 (VT/GN) C4235C-15 RME22 (GN/WH)
Is a fluctuating AC voltage present?
Yes
GO to F3.
No
GO to F7.
F3 CHECK THE AUDIO DSP (Digital Signal Processing) MODULE VOLTAGE SUPPLY
- Ignition OFF.
- Disconnect: Audio DSP (Digital Signal Processing) Module C4235A.
- Operate the audio system in radio tuner (AM/FM) mode.
- Measure the voltage between the audio DSP (Digital Signal Processing) module, harness side and ground as follows:
Positive Meter Lead Negative Meter Lead Circuit C4235A-9 Ground SBB20 (GN/RD) C4235A-10 Ground SBB20 (GN/RD) C4235A-11 Ground SBB21 (GY/RD) C4235A-12 Ground SBB21 (GY/RD)
Are the voltages greater than 10 volts?
Yes
GO to F4.
No
VERIFY the Battery Junction Box (BJB) fuse 20 (20A) or 21 (20A) is OK. If OK, REPAIR the circuit. TEST the system for normal operation. If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short. [1][2]Diagrams By Number
F4 CHECK THE AUDIO DSP (Digital Signal Processing) MODULE GROUND CIRCUITS FOR CONTINUITY
- Ignition OFF.
- Disconnect: Negative Battery Cable.
- Measure the voltage between the audio DSP (Digital Signal Processing) module, harness side and ground as follows:
Positive Meter Lead Negative Meter Lead Circuit C4235A-22 Ground GD148 (BK/YE) C4235A-23 Ground GD148 (BK/YE) C4235A-24 Ground GD148 (BK/YE)
Are the resistances less than 5 ohms?
Yes
GO to F5.
No
REPAIR the circuit in question. TEST the system for normal operation.
F5 CHECK THE CIRCUITS TO THE SUSPECT SPEAKER FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect: Audio DSP (Digital Signal Processing) Module C4235A and C4235B.
- Ignition ON.
- Measure the voltage between the suspect speaker, harness side and ground as follows:
Suspect Speaker Positive Meter Lead Negative Meter Lead LH subwoofer C3307-1 VME01 (GN/VT) Ground C3307-2 RME01 (GY) Ground LR door C702-1 VME09 (WH/GN) Ground C702-2 RME09 (BN/YE) Ground LF door C523-1 VME07 (WH) Ground C523-1 RME07 (WH/BN) Ground LH tweeter C569-1 VME08 (GN/OG) Ground C569-2 RME08 (GY/OG) Ground LH front imaging C2358-1 VME28 (BN/VT) Ground C2358-4 RME28 (BN/GN) Ground
Suspect Speaker Positive Meter Lead Negative Meter Lead Center front imaging C2358-2 VME06 (GN) Ground C2358-5 RME06 (GY/YE) Ground RH front imaging C2358-3 VME29 (GN/WH) Ground C2358-6 RME29 (BU/WH) Ground RH tweeter C613-1 VME11 (VT/OG) Ground C613-2 RME11 (YE/OG) Ground RF door C612-1 VME10 (WH/VT) Ground C612-2 RME10 (WH/OG) Ground RR door C802-1 VME12 (BN/WH) Ground C802-2 RME12 (BN/BU) Ground Rear center imaging C3306-1 VME30 (GN/BN) Ground C3306-2 RME30 (VT/BN) Ground RH subwoofer C3308-1 VME02 (VT) Ground C3308-2 RME02 (YE) Ground
Is any voltage present?
Yes
REPAIR the circuit in question. CLEAR any DTCs present. TEST the system for normal operation.
No
GO to F6.
F6 CHECK THE CIRCUITS TO THE SUSPECT SPEAKER 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:
Suspect Speaker Positive Meter Lead Negative Meter Lead Circuit LH subwoofer C3307-1 C4235A-16, then ground VME01 (GN/VT) C3307-2 C4235A-4, then ground RME01 (GY) LR door C702-1 C4235A-18, then ground VME09 (WH/GN) C702-2 C4235A-6, then ground RME09 (BN/YE) LF door C523-1 C4235B-9, then ground VME07 (WH) C523-2 C4235B-2, then ground RME07 (WH/BN) LH tweeter C569-1 C4235B-11, then ground VME08 (GN/OG) C569-2 C4235B-4, then ground RME08 (GY/OG) LH front imaging C2358-1 C4235A-14, then ground VME28 (BN/VT) C2358-4 C4235A-2, then ground RME28 (BN/GN)
Suspect Speaker Positive Meter Lead Negative Meter Lead Circuit Center front imaging C2358-2 C4235B-13, then ground VME06 (GN) C2358-5 C4235B-6, then ground RME06 (GY/YE) RH front imaging C2358-3 C4235B-14, then ground VME29 (GN/WH) C2358-6 C4235B-7, then ground RME29 (BU/WH) RH tweeter C613-1 C4235B-10, then ground VME11 (VT/OG) C613-2 C4235B-3, then ground RME11 (YE/OG) RF door C612-1 C4235B-8, then ground VME10 (WH/VT) C612-2 C4235B-1, then ground RME10 (WH/OG) RR door C802-1 C4235A-17, then ground VME12 (BN/WH) C802-2 C4235A-5, then ground RME12 (BN/BU) Rear center imaging C3306-1 C4235B-12, then ground VME30 (GN/BN) C3306-2 C4235B-5, then ground RME30 (VT/BN) RH subwoofer C3308-1 C4235A-15, then ground VME02 (VT) C3308-2 C4235A-3, then ground RME02 (YE)
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 F9.
No
REPAIR the circuit in question. CLEAR any DTCs present. TEST the system for normal operation.
F7 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 or C240D.
- Ignition ON.
- Measure the voltage between the audio DSP (Digital Signal Processing) module, harness side and ground as follows:
Suspect Speaker Positive Meter Lead Negative Meter Lead All LH speakers (without navigation), LF door or LF tweeter (with navigation) C4235C-7 VME07 (WH) Ground C4235C-17 RME07 (WH/BN) Ground All RH speakers (without navigation), RF door or RF tweeter (with navigation) C4235C-8 VME10 (WH/VT) Ground C4235C-18 RME10 (WH/OG) Ground LR door (with navigation) C4235C-4 VME09 (WH/GN) Ground C4235C-14 RME09 (BN/YE) Ground RR door (with navigation) C4235C-10 VME12 (BN/WH) Ground C4235C-20 RME12 (BN/BU) Ground Instrument panel or parcel shelf (with navigation) C4235C-9 VME51 (BN/BU) Ground C4235C-19 RME51 (WH/BU) Ground Subwoofer #1 or #2 C4235C-5 VME22 (VT/GN) Ground C4235C-15 RME22 (GN/WH) Ground
Is any voltage present?
Yes
REPAIR the circuit in question. CLEAR any DTCs present. TEST the system for normal operation.
No
GO to F8.
F8 CHECK THE AUDIO CIRCUITS TO THE AUDIO DSP (Digital Signal Processing) MODULE FOR AN OPEN OR 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:
Without Navigation
Suspect Speaker Positive Meter Lead Negative Meter Lead Circuit All LH speakers C240A-8 C4235C-7, then ground VME07 (WH) C240A-21 C4235C-17, then ground RME07 (WH/BN) All RH speakers C240A-11 C4235C-8, then ground VME10 (WH/VT) C240A-12 C4235C-18, then ground RME10 (WH/OG)
With Navigation
Suspect Speaker Positive Meter Lead Negative Meter Lead Circuit LF door, LF tweeter C240A-8 C4235C-7, then ground VME07 (WH) C240A-21 C4235C-17, then ground RME07 (WH/BN) RF door, RF tweeter C240A-11 C4235C-8, then ground VME10 (WH/VT) C240A-12 C4235C-18, then ground RME10 (WH/OG) LR door C240A-9 C4235C-4, then ground VME09 (WH/GN) C240A-22 C4235C-14, then ground RME09 (BN/YE) RR door C240A-10 C4235C-10, then ground VME12 (BN/WH) C240A-23 C4235C-20, then ground RME12 (BN/BU) Instrument panel, parcel shelf C240D-5 C4235C-9, then ground VME51 (BN/BU) C240D-6 C4235C-19, then ground RME51 (WH/BU) Subwoofer #1, subwoofer #2 C240D-1 C4235C-5, then ground VME22 (VT/GN) C240D-2 C4235C-15, then ground RME22 (GN/WH)
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 F10.
No
REPAIR the circuit in question. CLEAR any DTCs present. TEST the system for normal operation.
F9 CHECK FOR CORRECT AUDIO DSP (Digital Signal Processing) MODULE OPERATION
- Ignition OFF.
- 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 . CLEAR any DTCs present. 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.
F10 CHECK FOR CORRECT ACM (Audio Control Module) OPERATION
- Ignition OFF.
- 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) - MKZ . CLEAR any DTCs present. 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.