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. 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 SVC mode setting in audio unit sound adjustment set-up.
Is the SVC set to off?
YES - Change setting to MID and retest.
NO - Go to step 3.
3. Do the self-diagnostic function for the vehicle speed pulse indication.
Does self-diagnostic function indicate a VSP signal?
YES - Substitute a known-good audio unit and retest. If the symptom/indication goes away, replace the original audio unit.
NO -
- 1 CD type: Go to step 4.
- Except 1 CD type: Check for B-CAN DTCs (communication BUS Line Error) with the HDS and go to the indicated DTCs troubleshooting. If no B-CAN DTCs or communication bus line errors are found, substitute a known-good audio unit and recheck. If the symptom goes away, replace the original audio unit.
4. Remove the audio unit, and disconnect audio unit connector A (24P).
NOTE: Eject all the CDs before removing the audio unit and CD changer to prevent damaging the CD player's load mechanism.
5. Turn the ignition switch to ON (II).
6. Test-drive the vehicle and have an assistant measure the voltage at audio unit connector A (24P) No. 15 terminal.
NOTE: Some volt meters may show an average of 2.5 V, and others may show a constant voltage, depending on the meter's measurement speed.
Is there 0 - 5 V pulse?
YES - Substitute a known-good audio unit and recheck. If the symptom/indication goes away, replace the audio unit.
NO - Repair opens or shorts in the wire between the audio unit connector A (24P) No. 15 terminal and the ECM/PCM connector A (49P) No. 30 terminal. If no opens are found, substitute a known-good ECM/PCM and recheck. If the symptom/indicated goes away, replace the original ECM/PCM.