USB input sound is low or cannot be heard (without navigation)

WARNING: This page is about a different car, the 2011 Acura TL, 2010 Acura TL, and 2009 Acura TL. However, it is still accessible from the selected car via links, so may be relevant.

NOTE:

Check the vehicle battery condition first (see BATTERY TEST )
Check the connectors for poor connections or loose terminals
Not all players and player functions work with the USB adapter Please see the owner's manual for more information

Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
Do the speaker check mode with the self-diagnostic mode (see SPEAKER CHECK MODE )
Do all speakers make a sound?

YES -Go to step 3

NO -Go to NO SOUND IS HEARD FROM THE SPEAKER(S) (DISPLAY IS NORMAL) (WITHOUT NAVIGATION)
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
On the client's vehicle, connect the client's USB device to the USB adapter
Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
Turn on the audio system
Press the AUX button until USB appears on the audio display
Check if the USB device can be operated with the audio-navigation unit (Folders or Files UP/DOWN, etc.)
Can you operate the USB device, but there is no sound heard?

YES -Go to step 9

NO -If the sound is normal, the USB device is OK at this time If the USB device cannot be operated, go to USB DEVICE DOES NOT FUNCTION (WITHOUT NAVIGATION)
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
Connect the client's USB device to a known-good vehicle (same year/trim) that is equipped with a USB adapter, and check the USB device operation
Is the USB device working properly in the known-good vehicle?

YES -Go to step 11

NO -USB device is faulty Also check the USB cable and USB adapter connector condition
Return to the client's vehicle
Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode
Turn on the audio unit, and check for sound in each mode (XM and Bluetooth audio)
Is the sound normal?

YES -Go to step 14

NO -Go to XM or HFL SYSTEM TROUBLESHOOTING .
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode
Measure the voltage between USB adapter control unit connector A (14P) terminal No. 1 and body ground.

Fig 1: Measuring Voltage Between USB Adapter Unit Connector A (14P) Terminals No 1 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?

YES -Go to step 17

NO -Go to step 16
Measure the voltage between audio unit connector C (14P) terminal No. 1 and body ground.

Fig 2: Measuring Voltage Between Audio Unit Connector C (14P) Terminal No. 1 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?

YES -Repair an open or high resistance in the wire between the USB adapter control unit connector A (14P) terminal No. 1 and audio unit connector C (14P) terminal No. 1.

NO -Replace the audio unit (see AUDIO UNIT REMOVAL/INSTALLATION )
Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
Measure the voltage between USB adapter control unit connector A (14P) terminal No. 11 and body ground.

Fig 3: Measure The Voltage Between Usb Adapter Control Unit Connector A (14P) Terminal No. 11 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there less than 0.2 V?

YES -Go to step 19

NO -Repair an open or high resistance in the wire between USB adapter control unit connector A (14P) terminal No. 11 and audio unit connector C (14P) terminal No. 11.
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
Disconnect these items:
- Audio unit connector C (14P)
- USB adapter control unit connector A (14P)
- XM receiver connector A (14P)
Check for continuity between USB adapter control unit connector A (14P) terminal No. 2 and body ground.

Fig 4: Measure The Voltage Between Usb Adapter Control Unit Connector A (14P) Terminal No. 11 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES -Repair a short to body ground in the wire between USB adapter control unit connector A (14P) terminal No. 2 and audio unit connector C (14P) terminal No. 2.

NO -Go to step 22
Check for continuity between audio unit connector C (14P) terminal No. 2 and USB adapter control unit connector A (14P) terminal No. 2.

Fig 5: Identifying USB Adapter Unit Connector A (14P) Terminals
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES -Go to step 23

NO -Repair an open in the wire between audio unit connector C (14P) terminal No. 2 and USB adapter control unit connector A (14P) terminal No. 2.

Check for continuity between audio unit connector C (14P) and the USB adapter unit connector A14P according to the table

USB ADAPTER UNIT CONNECTOR REFERENCE CHART

Audio unit connector	USB adapter unit connector	Wire color
C5	A5	GRN
C6	A6	BLK
C13	A13	WHT
C14	A14	RED

Fig 6: Identifying Audio Unit Connector C (14P) Terminals

Courtesy of AMERICAN HONDA MOTOR CO., INC.

Fig 7: Identifying USB Adapter Unit Connector A (14P) Terminals

Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES -Substitute a known-good USB adapter unit (see USB ADAPTER UNIT REPLACEMENT ) then reconnect all of the connectors, and recheck If the symptom/indication goes away, replace the original USB adapter unit. If the symptom/indication is still present, replace the audio unit (see AUDIO UNIT REMOVAL/INSTALLATION )

NO -There is an open in the wire(s) between the audio unit and the USB adapter unit. Replace the affected shielded harness