Volume Does Not Increase With Speed
Volume does not increase with speedNOTE:
- Check the vehicle battery condition first.
- Check the connectors for poor connections or loose terminals.
1. Verify the SVC mode setting in the navigation or audio unit sound set-up.
Is the SVC set to off?
YES - Change the setting to Mid and retest.
NO - Go to step 2.
2. Do the self-diagnostic function for the vehicle speed pulse indication.
Does the self-diagnostic function indicate a VSP signal?
YES - Substitute a known-good navigation or audio unit and retest. If the symptom/indication goes away, replace the original navigation or audio unit.
NO - Go to step 3.
3. 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 4.
4. Remove the navigation unit, or audio unit, and disconnect the navigation, or audio unit connector A (17P).
NOTE: Eject all the discs before removing the audio unit or navigation unit to prevent damaging the CD player's load mechanism.
5. Drive the vehicle, and have an assistant measure voltage at navigation or audio unit connector A (17P) terminal No. 13.
Is there a 0 - 5 V Pulse?
YES -
- With navigation: Replace the navigation unit.
- Without navigation: Replace the audio unit.
NO - Repair open or shorts in the wire between the navigation, or audio unit connector A (17P) No. 13 terminal and the ECM/PCM connector A (44P) No. 29 terminal. If no opens or shorts are found, substitute a known-good ECM/PCM and recheck. If the symptom/indication goes away, replace the original ECM/PCM.