Booming Sound While Driving With Audio Unit ON or OFF

Audio System Symptom Troubleshooting - Booming sound while driving with audio unit on or off

Booming sound while driving with audio unit on or off

NOTE:

- Check the vehicle battery condition first Battery Test.
- Check the connectors for poor connections or loose terminals.

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

2. Operate the audio system, and the speakers function normally.

Is a booming sound or a low-frequency hum heard from speakers?

YES -

Go to step 3.

NO -

Operation is normal.

3. Open the driver's door, with the booming sound present.

Is the booming sound still present?

YES -

Go to step 62.

NO -

Go to step 4.

4. Turn the audio system off.

5. Do the ANC/active sound control Self-Diagnostic Function.

6. Press the No. 1 button.

Is the low-frequency hum sound heard?

YES -

Go to step 7.

NO -

Go to step 29.

7. Check that the low-frequency hum sound continues sounding for about 1 minute.

Does the low-frequency hum sound continue sounding for about 1 minute?

YES -

Go to step 52.

NO -

Go to step 8.

8. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

9. Check the No. 15 (10 A) fuse in the under-hood fuse/relay box.

Is the fuse OK?

YES -

Go to step 10.

NO -

Replace the fuse, and recheck. If the fuse blows again, check for a short in the No. 15 (10 A) fuse circuit.

10. Connect a voltmeter between ANC/active sound control unit 16P connector terminals No. 3 and No. 11.

NOTE: Use the voltmeter in AC range.






11. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

12. Make a loud noise in front of the microphone.

Does the voltage change when making a loud noise in front of the microphone?

YES -

Replace the ANC/active sound control unit Service and Repair.

NO -

Go to step 13.

13. Measure the voltage between body ground and front HFL-navigation-ANC/active sound control microphone 7P connector or front HFL-ANC/active sound control microphone 7P connector terminals No. 6 and No. 7 individually.





Is there battery voltage?

YES -

Go to step 14.

NO -

If the+B wire does not have voltage, repair an open in the wire between the No. 15 (10 A) fuse in the under-hood fuse/relay box and the front HFL-navigation-ANC/active sound control microphone or the front HFL-ANC/active sound control microphone. If the ACC wire does not have voltage, repair an open in the wire between the No. 18 (7.5 A) fuse in the driver's under-dash fuse/relay box and the front HFL-navigation-ANC/active sound control microphone or the front HFL-ANC/active sound control microphone.

14. Measure the voltage between front HFL-navigation-ANC/active sound control microphone 7P connector or front HFL-ANC/active sound control microphone 7P connector terminal No. 1 and body ground.





Is there less than 0.2 V?

YES -

Go to step 15.

NO -

Repair open or high resistance in the wire between the front HFL-navigation-ANC/active sound control microphone or the front HFL-ANC/active sound control microphone and body ground (G402).

15. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

16. Disconnect these items:

- ANC/active sound control unit 16P connector
- Front HFL-navigation-ANC/active sound control microphone 7P connector (with navigation)
- Front HFL-ANC/active sound control microphone 7P connector (without navigation)

17. Check for continuity between ANC/active sound control unit 16P connector terminal No. 3 and the front HFL-navigation-ANC/active sound control microphone 7P connector or front HFL-ANC/active sound control microphone 7P connector terminal No. 4.





Is there continuity?

YES -

Go to step 18.

NO -

There is an open in the wire between ANC/ active sound control unit and the front HFL-navigation-ANC/active sound control microphone or the front HFL-ANC/active sound control microphone. Replace the affected shielded harness.

18. Check for continuity between ANC/active sound control unit 16P connector terminal No. 3 and body ground.





Is there continuity?

YES -

There is a short to body ground in the wire between the ANC/active sound control unit and the front HFL-navigation-ANC/active sound control microphone or the front HFL-ANC/active sound control microphone. Replace the affected shielded harness.

NO -

Go to step 19.

19. Connect a voltmeter between ANC/active sound control unit 16P connector terminals No. 4 and No. 5.

NOTE: Use the voltmeter in AC range.






20. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

21. Make a loud noise in front of the rear ANC/active sound control microphone.

Does the voltage change when making a loud noise in front of the microphone?

YES -

Replace the ANC/active sound control unit Service and Repair.

NO -

Go to step 22.

22. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

23. Disconnect the rear ANC/active sound control microphone 2P connector.

24. Connect rear ANC/active sound control microphone 2P connector terminals No. 1 and No. 2 with a jumper wire.






25. Check for continuity between ANC/active sound control unit 16P connector terminals No. 4 and No. 5.





Is there continuity?

YES -

Go to step 26.

NO -

There is an open in the wire(s) between the ANC/active sound control unit and the rear ANC/active sound control microphone. Replace the affected shielded harness.

26. Remove the jumper wire.

27. Check for continuity between ANC/active sound control unit 16P connector terminals No. 4 and No. 5.





Is there continuity?

YES -

There is a short in the wires between the ANC/ active sound control unit and the rear ANC/active sound control microphone. Replace the affected shielded harness.

NO -

Go to step 28.

28. Check for continuity between ANC/active sound control unit 16P connector terminal No. 4 and body ground.





Is there continuity?

YES -

There is a short to body ground in the wire between the ANC/active sound control unit and the rear ANC/active sound control microphone. Replace the affected shielded harness.

NO -

Replace the front HFL-navigation-ANC/active sound control microphone Front HFL-Navigation-ANC/Active Sound Control Microphone Removal / Installation or the front HFL-ANC/active sound control microphone Front HFL-ANC/Active Sound Control Microphone Removal / Installation and the rear ANC/active sound control microphone Service and Repair at once, and recheck. If the symptom/indication still present, replace the ANC/active sound control unit Service and Repair.

29. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

30. Check the No. 15 (10 A) fuse in the under-hood fuse/relay box.

Is the fuse OK?

YES -

Go to step 31.

NO -

Replace the fuse, and recheck. If the fuse blows again, check for a short in the No. 15 (10 A) fuse circuit.

31. Measure the voltage between ANC/active sound control unit 16P connector terminal No. 8 and body ground.





Is there battery voltage?

YES -

Go to step 32.

NO -

Repair an open in the wire between the No. 15 (10 A) fuse in the under-hood fuse/relay box and the ANC/active sound control unit.

32. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

33. Measure the voltage between ANC/active sound control unit 16P connector terminal No. 6 and body ground.





Is there battery voltage?

YES -

Go to step 34.

NO -

Repair an open in the wire between ANC/active sound control unit 16P connector terminal No. 6 and audio-navigation unit connector A (24P) or audio unit connector A (24P) terminal No. 17.

34. Measure the voltage between ANC/active sound control unit 16P connector terminal No. 7 and body ground.





Is there less than 0.2 V?

YES -

Go to step 35.

NO -

Repair an open or high resistance in the wire between the ANC/active sound control unit and body ground (G501) Audio Wire Harness.

35. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

36. Do the ANC/active sound control Self-Diagnostic Function.

37. Press the No. 1 button.

38. Measure the voltage between ANC/active sound control unit 16P connector terminal No. 12 and body ground.





Is there about 5.0 V?

YES -

Go to step 44.

NO -

Go to step 39.

39. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

40. Disconnect these items:

- ANC/active sound control unit 16P connector
- Audio-navigation unit connector H (28P) (with navigation)
- Audio unit connector B (24P) (without navigation)

41. Check for continuity between ANC/active sound control unit 16P connector terminal No. 12 and body ground.





Is there continuity?

YES -

Repair a short to body ground in the wire between the ANC/active sound control unit and the audio unit.

NO -

- With navigation, go to step 42.
- Without navigation, go to step 43.

42. Check for continuity between ANC/active sound control unit 16P connector terminal No. 12 and audio-navigation unit connector H (28P) terminal No. 21.





Is there continuity?

YES -

Substitute a known-good audio-navigation unit (including the HDD) 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 -

Repair an open in the wire between the ANC/active sound control unit and the audio-navigation unit.

43. Check for continuity between ANC/active sound control unit 16P connector terminal No. 12 and audio unit connector B (24P) terminal No. 7.





Is there continuity?

YES -

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

NO -

Repair an open in the wire between the ANC/active sound control unit and the audio unit.

44. Do the ANC/active sound control Self-Diagnostic Function.

45. Press the No. 1 button.

46. Measure the voltage between ANC/active sound control unit 16P connector terminal No. 2 and body ground.





Is there about 2.5 V?

YES -

Replace the stereo amplifier Service and Repair.

NO -

Go to step 47.

47. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

48. Disconnect the ANC/active sound control unit 16P connector and stereo amplifier connector C (5P).

49. Check for continuity between body ground and the ANC/active sound control unit 16P connector according to the table.









Is there continuity?

YES -

There is a short to body ground in the wire(s) between the ANC/active sound control unit and the stereo amplifier. Replace the affected shielded harness.

NO -

Go to step 50.

50. Check for continuity between the terminals of the ANC/active sound control unit 16P connector according to the table.









Is there continuity between any of the terminals?

YES -

There is a short in the wires between the ANC/active sound control unit and the stereo amplifier. Replace the affected shielded harness.

NO -

Go to step 51.

51. Check for continuity between the ANC/active sound control unit 16P connector and stereo amplifier connector C (5P) according to the table.













Is there continuity?

YES -

Replace the ANC/active sound control unit Service and Repair.

NO -

There is an open in the wire(s) between the ANC/active sound control unit and the stereo amplifier. Replace the affected shielded harness.

52. Start the engine, and let the vehicle idle.

53. Do the ANC/active sound control Self-Diagnostic Function.

54. Press the No. 1 button.

Can you hear the low-frequency hum?

YES -

Go to step 55.

NO -

The system is OK.

55. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

56. Disconnect the ANC/active sound control unit 16P connector.

57. Jump the SCS line with the HDS.

58. Disconnect PCM connector A (49P).

59. Check for continuity between ANC/active sound control unit 16P connector terminal No. 15 and PCM connector A (49P) terminal No. 33.





Is there continuity?

YES -

Go to step 60.

NO -

Repair an open in the wire between the ANC/ active sound control unit and the PCM.

60. Disconnect the ECPS control unit 12P connector.

61. Check for continuity between ANC/active sound control unit 16P connector terminal No. 15 and body ground.





Is there continuity?

YES -

Repair a short in the wire between the ANC/active sound control unit and the PCM.

NO -

Substitute a known-good ANC/active sound control unit Service and Repair, and recheck. If the symptom/indication goes away, replace the original ANC/active sound control unit Service and Repair. If symptom/indication is still present, update the PCM PCM Update if it does not have the latest software or substitute a known-good PCM.

62. Measure the voltage between ANC/active sound control unit 16P connector terminal No. 16 and body ground while the door is opening.





Is there about 5.0 V?

YES -

Replace the ANC/active sound control unit Service and Repair.

NO -

Repair an open in the wire between the ANC/active sound control unit and driver's under-dash fuse/relay box connector P (20P) terminal No. 4.