Volume does not increase with speed (without navigation)

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

NOTE:

Check the vehicle battery condition first (see 12 VOLT BATTERY TEST ).
Check the connectors for poor connections or loose terminals.

Verify SVC mode setting in the audio unit sound set-up.
Is the SVC set to off?

YES -Change setting to MID, and retest.

NO -go to step 2.
Do the self-diagnostic function for the vehicle speed pulse indication (see SELF-DIAGNOSTIC FUNCTION ).
Does the self-diagnostic function indicate a VSP signal when the vehicle is moving?

YES -Substitute a known-good audio unit (see AUDIO UNIT REMOVAL/INSTALLATION ), and recheck. If the symptom/indication goes away, replace the original audio unit.

NO -go to step 3.
Test-drive the vehicle at highway speeds, and monitor if the volume increases.
Does the volume increase?

YES -Intermittent failure, the system is OK at this time.

NO -
- Except DX model: Go to step 4.
- DX model: Go to step 8.
Turn the ignition switch to LOCK (0).
Remove the audio unit (see AUDIO UNIT REMOVAL/INSTALLATION ), and disconnect audio unit connector A (24P).
NOTE: Eject all the discs before removing the audio unit to prevent damaging the CD player's load mechanism.
Turn the ignition switch to ON (II).
Drive the vehicle, and have an assistant measure the voltage at audio unit connector A (24P) terminal No. 15 and body ground.
NOTE: Some voltmeters may show an average of 2.5V, and others may show a constant voltage, depending on the meter's measurement speed.

Fig 1: Measuring Voltage At Audio Unit Connector A (24P) Terminal No. 15 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there a 0-5 V pulse or about 2.5 V average?

YES -Substitute a known-good audio unit (see AUDIO UNIT REMOVAL/INSTALLATION ), and recheck. If the symptom/indication goes away, replace the original audio unit.

NO -Repair an opens or a shorts in the wire between audio unit connector A(24P) terminal No. 15 and PCM connector A (44P) terminal No. 29. If no opens are found, substitute a known-good PCM (see SUBSTITUTING THE PCM ), and recheck. If the symptom/indication goes away, replace the original PCM (see PCM REPLACEMENT ).
Turn the ignition switch to LOCK (0).
Remove the audio unit, and disconnect audio unit connector A (17P).
NOTE: Eject all the discs before removing the audio unit to prevent damaging the CD player's load mechanism.
Turn the ignition switch to ON (II).
Drive the vehicle, and have an assistant measure the voltage between audio unit connector A (17P) terminal No. 13 and body ground.
NOTE: Some voltmeters may show an average of 2.5 V, and others may show a constant voltage, depending on the meter's measurement speed.

Fig 2: Measuring Voltage At Audio Unit Connector A (17P) Terminal No. 13 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there a 0-5 V pulse or about 2.5 V average?

YES -Substitute a known-good audio unit (see AUDIO UNIT REMOVAL/INSTALLATION ), and recheck. If the symptom/indication goes away, replace the original audio unit.

NO -Repair an opens or a shorts in the wire between audio unit connector A(17P) terminal No. 13 and PCM connector A (44P) terminal No. 29. If no opens are found, substitute a known-good PCM (see SUBSTITUTING THE PCM ), and recheck. If the symptom/indication goes away, replace the original PCM (see PCM REPLACEMENT ).