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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 Testing and Inspection.
- Check the connectors for poor connections or loose terminals.

1. Test-drive the vehicle at highway speeds, and monitor if the volume increases.

Do the volume increase?

YES -

Intermittent failure, the system is OK at this time.�

NO -

Go to step 2.

2. Verify the SVC mode setting in the audio-navigation unit sound set-up.

Is the SVC set to off?

YES -

Change the setting to SVC MID, and recheck Description and Operation.�

NO -

Go to step 3.

3. Do the Self-Diagnostic Function for the vehicle speed pulse indication Audio System Self-Diagnostic Function.

Does the self-diagnostic function indicate a VSP signal?

YES -

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

NO -

Go to step 4.

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

NOTE:

- Eject all the discs before removing the audio-navigation unit to prevent damaging the CD player's load mechanism.
- Remove the PC card before removing the audio-navigation unit.

5. Drive the vehicle and have an assistant, measure the voltage between audio-navigation unit connector A (24P) terminal No. 15 and body ground.





Is there a 0-5 V Pulse?

YES -

Replace the audio-navigation unit Audio-Navigation Unit Removal/Installation.�

NO -

Repair an open or short in the wire between audio-navigation unit connector A (24P) terminal No. 15 and PCM connector A (44P) terminal No. 29. If no opens or shorts are found, Update the PCM PCM Update if it does not have the latest software, or substitute a known-good PCM Initial Inspection and Diagnostic Overview.�