Symptom Troubleshooting

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

Booming sound while driving with audio unit on or off (Without navigation and rear entertainment system)

NOTE:

- Check the vehicle battery condition first Testing and Inspection.
- Check the connectors for poor connections or loose terminals.
- Check for all system's DTCs first with the HDS. If there are any DTCs stored, go to the indicated DTC's troubleshooting.

1. Turn the ignition switch to ON (II).

2. Operate the audio unit, and check the function of the speakers.

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

YES -

Go to step 3.

NO -

Go to no sound is heard from the speaker(s) No Sound Is Heard From The Speaker(s) From All Inputs (Display Is Normal) (Without Navigation And Rear Entertainment System).�

3. Turn the audio system off.

4. Make sure all doors, hood and the tailgate are closed.

5. Start the engine, and let it idle.

6. Do the active noise cancellation (ANC) self-diagnostic function.

7. Check the test items on tests 1 thru 8.

NOTE: Move to the next test item within 50 seconds, or the self-diagnostic test ends.

Do you hear a low-frequency hum from the speakers for more than 5 seconds for all the tests?

YES -

Go to step 8.

NO -

Go to the appropriate step listed.

- If all test items failed, replace the audio unit Audio Unit Removal/Installation.
- If the 3rd test failed (front speaker output), replace the audio unit Audio Unit Removal/Installation.
- If the 4th test failed (Rear speaker output), replace the audio unit Audio Unit Removal/Installation.
- If the 5th test failed (ANC front mic input), go to step 25.
- If the 6th test failed (ANC rear mic input), go to step 36.
- If the 7th test failed (NEP (RPM) input), go to step 47.
- If the 8th test failed (door/trunk input), go to step 66.

8. Turn the ignition switch to LOCK (0).

9. Connect the HDS to the DLC Reading and Clearing Diagnostic Trouble Codes.

10. Turn the ignition switch to ON (II).

11. Select PGM-FI SYSTEM with the HDS.

12. Select VTEC TEST in the INSPECTION MENU with the HDS.

13. Select SOLENOID VALVE ACTIVATION, and prepare to do the function test.

14. Do the active noise cancellation (ANC) self-diagnostic function.

15. Go to the 8th test by pressing the No. 1 button.

16. Select ROCKER ARM OIL CONTROL SOLENOID A (B1) ON with the HDS, and move on to the 9th test pressing the No. 1 button.

Do you hear a low-frequency hum from the speakers for more than 5 seconds?

YES -

Go to step 17.

NO -

Go to step 59.

17. Select ROCKER ARM OIL CONTROL SOLENOID A (B2) ON with the HDS, and go to the 10th test by pressing the No. 1 button.

Do you hear a low-frequency hum from the speakers for more than 5 seconds?

YES -

Go to step 18.

NO -

Go to step 73.

18. Turn the ignition switch to LOCK (0).

19. Disconnect the HDS from the DLC.

20. Start the engine, and let it idle.

21. Do the active noise cancellation (ANC) self-diagnostic function.

22. Go to the 10th test by pressing the No. 1 button.

23. Set the parking brake, then hold the engine speed at 2,500 rpm in P, and go to the 11th test by pressing the No. 1 button.

24. Press the No. 1 button several times to turn the ANC on and off.

Do you hear a low-frequency hum from the speakers change when you press the No. 1 button?

YES -

Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals between the audio unit, the PCM, and the under dash fuse box. Then, go to step 1, and recheck.

NO -

Replace the audio unit Audio Unit Removal/Installation.�

25. Turn the ignition switch to LOCK (0).

26. Connect a voltmeter between audio unit connector E (16P) terminal No. 4 and No. 11.

NOTE: Use the voltmeter in AC range.

27. Turn the ignition switch to ON (II).

28. Make a loud noise in front of the front active noise cancellation microphone by clapping your hands.

Does the voltage change about 0.5 V AC when you make a loud noise in front of the front active noise cancellation microphone?

YES -

Replace the audio unit Audio Unit Removal/Installation.�

NO -

Go to step 29.

29. Turn the ignition switch to LOCK (0).

30. Disconnect audio unit connector E (16P) and the front active noise cancellation microphone 3P connector.

31. Check for continuity between audio unit connector E (16P) terminals No. 4 and No. 11.

Is there continuity?

YES -

Go to step 32.

NO -

There is an open in the wire(s) between audio unit connector E (16P) and the front active noise cancellation microphone 3P connector. Replace the affected shielded harness.�

32. Connect front active noise cancellation microphone 3P connector terminals No. 1 and No. 3 with a jumper wire.

33. Remove the jumper wire from the front active noise cancellation microphone 3P connector.

34. Check for continuity between audio unit connector E (16P) terminals No. 4 and No. 11.

Is there continuity?

YES -

There is a short in the wires between audio unit connector E (16P) and the front active noise cancellation microphone 3P connector. Replace the affected shielded harness.�

NO -

Go to step 35.

35. Check for continuity between audio unit connector E (16P) terminal No. 4 and body ground.

Is there continuity?

YES -

There is a short to body ground in the wire between the audio unit and the front active noise cancellation microphone. Replace the affected shielded harness.�

NO -

Replace the front active noise cancellation microphone Active Noise Cancellation Microphone Removal/Installation.�

36. Turn the ignition switch to LOCK (0).

37. Connect a voltmeter between audio unit connector E (16P) terminals No. 5 and No. 12.

NOTE: Use the voltmeter in AC range.

38. Turn the ignition switch to ACCESSORY (I).

39. Make a loud noise in front of the rear active noise cancellation microphone by clapping your hands.

Does the voltage change about 0.5 V AC when you make a loud noise in front of the rear active noise cancellation microphone?

YES -

Replace the audio unit Audio Unit Removal/Installation.�

NO -

Go to step 40.

40. Turn the ignition switch to LOCK (0).

41. Disconnect audio unit connector E (16P) and the rear active noise cancellation microphone 2P connector.

42. Connect rear active noise cancellation microphone 2P connector terminals No. 1 and No. 2 with a jumper wire.

43. Check for continuity between audio unit connector E (16P) terminals No. 5 and No. 12.

Is there continuity?

YES -

Go to step 44.

NO -

There is an open in the wire(s) between audio unit connector E (16P) and the rear active noise cancellation microphone 2P connector. Replace the affected shielded harness.�

44. Remove the jumper wire from the rear active noise cancellation microphone 2P connector.

45. Check for continuity between audio unit connector E (16P) terminals No. 5 and No. 12.

Is there continuity?

YES -

There is a short in the wires between the audio unit and the rear active noise cancellation microphone. Replace the affected shielded harness.�

NO -

Go to step 46.

46. Check for continuity between audio unit connector E (16P) terminal No. 5 and body ground.

Is there continuity?

YES -

There is a short to body ground in the wire between the audio unit and the rear active noise cancellation microphone. Replace the affected shielded harness.�

NO -

Replace the rear active noise cancellation microphone.�

47. Turn the ignition switch to LOCK (0).

48. Start the engine, and let it idle.

49. Measure the voltage between audio unit connector E (16P) terminal No. 15 and body ground.

Is there about 5 V?

YES -

Replace the audio unit Audio Unit Removal/Installation.�

NO -

Go to step 50.

50. Turn the ignition switch to LOCK (0).

51. Jump the SCS line with the HDS.

52. Disconnect audio unit connector E (16P) and PCM connector A (49P).

53. Connect PCM connector A (49P) terminal No. 33 to body ground with a jumper wire.

54. Check for continuity between audio unit connector E (16P) terminal No. 15 and body ground.

Is there continuity?

YES -

Go to step 55.

NO -

Repair an open in the wire between audio unit connector E (16P) and PCM connector A (49P).�

55. Remove the jumper wire from PCM connector A (49P).

56. Check for continuity between audio unit connector E (16P) terminal No. 15 and body ground.

Is there continuity?

YES -

Repair a short to body ground in the wire between audio unit connector E (16P) and PCM connector A (49P).�

NO -

Update the PCM PCM Update if it does not have the latest software or substitute a known-good PCM.�

57. Turn the ignition switch to LOCK (0).

58. Do the MICU input test MICU And Door Multiplex Control Unit Input Test.

Is the B-CAN line between the audio unit and the MICU OK?

YES -

Replace the audio unit Audio Unit Removal/Installation.�

NO -

Repair an open in the wire between audio unit connector D (20P) and MICU connector T (34P).�

59. Turn the ignition switch to LOCK (0).

60. Connect a voltmeter between audio unit connector E (16P) terminals No. 13 to body ground.

61. Connect the HDS to the DLC Reading and Clearing Diagnostic Trouble Codes.

62. Turn the ignition switch to ON (II).

63. Select PGM-FI SYSTEM with the HDS.

64. Select VTEC TEST in the INSPECTION MENU with the HDS.

65. Select ROCKER ARM OIL CONTROL SOLENOID A (B1) ON in the SOLENOID VALVE ACTIVATION with the HDS, and measure the voltage.

Is the voltage between 5 V and battery voltage?

YES -

Replace the audio unit Audio Unit Removal/Installation.�

NO -

Go to step 66.

66. Turn the ignition switch to LOCK (0).

67. Jump the SCS line with the HDS.

68. Disconnect audio unit connector E (16P) and PCM connector A (49P).

69. Connect PCM connector A (49P) terminal No. 14 to body ground with a jumper wire.

70. Check for continuity between audio unit connector E (16P) terminal No. 13 and body ground.

Is there continuity?

YES -

Go to step 71.

NO -

Repair an open in the wire between audio unit connector E (16P) and PCM connector A (49P).�

71. Remove the jumper wire from PCM connector A (49P).

72. Check for continuity between audio unit connector E (16P) terminal No. 13 and body ground.

75. Connect the HDS to the DLC Reading and Clearing Diagnostic Trouble Codes.

76. Turn the ignition switch to ON (II).

77. Select PGM-FI SYSTEM with the HDS.

78. Select VTEC TEST in the INSPECTION MENU with the HDS.

79. Select ROCKER ARM OIL CONTROL SOLENOID A (B2) ON in the SOLENOID VALVE ACTIVATION with the HDS, and measure the voltage.

Is the voltage about 10 V?

YES -

Replace the audio unit Audio Unit Removal/Installation.�

NO -

Go to step 80.

80. Turn the ignition switch to LOCK (0).

81. Jump the SCS line with the HDS.

82. Disconnect audio unit connector E (16P) and PCM connector A (49P).

83. Connect PCM connector A (49P) terminal No. 15 to body ground with a jumper wire.

84. Check for continuity between audio unit connector E (16P) terminal No. 14 and body ground.

Is there continuity?

YES -

Go to step 85.

NO -

Repair an open in the wire between audio unit connector E (16P) and PCM connector A (49P).�

85. Remove the jumper wire from PCM connector A (49P).

86. Check for continuity between audio unit connector E (16P) terminal No. 14 and body ground.