Volume Does Not Increase With Speed (With Navigation)

Audio System Symptom Troubleshooting - Volume does not increase with speed

Volume does not increase with speed (with navigation)

NOTE:

- Check the vehicle battery condition first Battery Test.
- Check the connectors for poor connections or loose terminals.
- Set the fader and balance positions to the center.

1. Check the SVC mode setting in the audio-navigation unit or audio unit sound setup.

Is the SVC set to off?

YES -

Change the setting to at least the MID setting, and retest.

NO -

Go to step 2.

2. Do the System Diagnostic Mode of Navigation System for the vehicle speed pulse indication (VSP) in the Car Status.

Does the Car Status indicate a VSP signal when the vehicle is moving?

YES -

Substitute a known-good audio-navigation unit Audio-Navigation Unit Removal/Installation (With Navigation) and retest. If the symptom/indication goes away, replace the original audio-navigation unit Audio-Navigation Unit Removal/Installation (With Navigation).

NO -

Go to step 3.

3. Test-drive the vehicle at highway speeds, and monitor if the volume increases with speed.

Does the volume increase?

YES -

Intermittent failure, the system is OK at this time.

NO -

Go to step 4.

4. Remove the audio-navigation unit Audio-Navigation Unit Removal/Installation (With Navigation), and disconnect audio-navigation unit connector A (24P).

5. Raise the vehicle on a lift.

6. Turn the ignition switch to ON (II).

7. Press the brake pedal, and shift the transmission to N.

8. Slowly spin one of the front wheels by hand, and have an assistant measure the voltage at audio-navigation unit connector A (24P) terminal No. 15.





Is there a 0-5 V pulse?

YES -

Replace the audio-navigation unit Audio-Navigation Unit Removal/Installation (With Navigation).

NO -

Repair an open or short in the wire between audio-navigation unit connector A (24P) terminal No. 15 and ECM/PCM connector A (44P) terminal No. 30. If no open or short is found, substitute a known-good ECM/PCM, and recheck. If the symptom/indicated goes away, replace the original ECM/PCM Service and Repair.