Volume does not increase with speed (without navigation)
- 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 adjustment set-up.
Is the SVC set to off?
YES -Change setting to MID, and recheck.
NO -Go to step 2.
- Do the self-diagnostic function for the vehicle speed pulse indication (see HOW TO CHECK THE AUDIO SYSTEM CONDITION
).
Does the self-diagnostic function indicate a VSP signal?
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 (see AUDIO UNIT REMOVAL/INSTALLATION ).
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 -Go to step 4.
- 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. 23 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.
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 (see AUDIO UNIT REMOVAL/INSTALLATION ).
NO -Repair an open or a short in the wire between audio unit connector A (24P) terminal No. 23 and ECM/PCM connector A (44P) terminal No. 29. If no opens are found, substitute a known-good ECM/PCM (see SUBSTITUTING THE ECM/PCM ), and recheck. If the symptom/indication goes away, replace the original ECM/PCM (see ECM/PCM REPLACEMENT ).