Volume Does Not Increase With Speed (With Navigation)

Symptom Troubleshooting: Volume does not increase with speed

Volume does not increase with speed (with navigation)

NOTE:

- Check the vehicle battery condition first.

- Check the connectors for poor connections or loose terminals.

1. 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 2.


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

Is the SVC set to off?
YES - Change the setting to Mid, and retest. Description and Operation

NO - Go to step 3.


3. Do the self-diagnostic function for the vehicle speed pulse indication. Initial Inspection and Diagnostic Overview

Does the self-diagnostic function indicate a VSP signal?
YES - Substitute a known-good navigation unit, Service and Repair and retest. If the symptom/indication goes away, replace the original navigation unit.

NO - Go to step 4.


4. Remove the navigation unit Service and Repair and disconnect navigation unit connector A (24P).
NOTE:

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

- Remove the PC card before removing the navigation unit.

5. Drive the vehicle, and have an assistant measure voltage at navigation unit connector A (24P) terminal No. 15.

Is there a 0-5 V Pulse?
YES - Replace the navigation unit. Service and Repair

NO - Repair open or short in the wire between navigation unit connector A (24P) terminal No. 15 and ECM/PCM connector A (44P) terminal No. 29. If no opens or shorts are found, substitute a known-good ECM/PCM. Service and Repair