I've noticed the "booming" sound in our 05 HAH for a few months, but we typically drive in speeds above 60 mph
where the sound doesn't occur, so it has been only a minor nuisance.
But, on a trip to Arkansas last week, driving on some mountain roads at 50-60 mph
, the booming noise became a major annoyance. I found myself punching the accelerator to get out of ECO into 6 cyl mode just to get rid of the noise.
I started watching the sound pattern closely and noted it was loudest and most common at these conditions: 1600-1700 rpm, ECO light on, slight deceleration. Driving at 55 mph
, ECO on, level road or slight decline, the sound was constant and close to unbearable.
Back home I did some searching and found this thread. Drivers at Green Hybrid are great resources. I did find the TSB 06-005 mentioned here; the title is: "Humming or Booming Comes From the Speakers".” I found it at this URL:
< http://www.alldata.com/tsb/Honda/index-post.html>. The page is a long list of TSBs; scroll down until you find this:
Wed, Apr 12, 2006 Fri, Mar 24, 2006 06-005 Audio System - Front Speaker Humming and or Booming Noise
The TSB is in two .jpg files which I can email if anyone is unable to access the file on the alldata.com web site.
The TSB states the “Probable Cause” of the “humming” is that “The ANC (active noise cancellation) unit is faulty.”
“Corrective Action” is to “Replace the ANC unit and the front speakers.”
The TSB provides a very simple “Diagnosis” procedure:
1. Remove lens from ceiling light (the one in center of roof); small screwdriver pops it right out.
2. Attach a 4 foot or longer jumper wire to the driver’s side terminal of the ceiling light bulb (alligator clip is nice, but a length of 14 gauge stranded copper wire will work fine).
3. Next step recommends 1 to drive, someone else to do the test, no doubt safer that way.
4. Drive to produce the humming sound (for me, that’s 55 mph
, 1600 rpm, level or slight decline with ECO on).
5. Ground the other end of the jumper wire to the “grounding sleeve” of the cig lighter/power outlet (the silver ring you plug devices into).
6. If the noise goes away, the ANC is faulty ; replace ANC and two front speakers.
Armed with a printout of the TSB, I took our HAH in to the small dealer in Ardmore, Ok where we bought it. Tech said ours was the first booming complaint. I provided him a copy of the TSB and suggested he grab a jumper wire and come for ride; he agreed. He first started to remove the cover of the map lights, and I pointed him to the center/ceiling light. Cover came off easily, and he clipped the jumper to the driver’s side pole. Once I got up the 1600 rpm, 55 mph
, ECO on status, he heard the booming right away; it’s loud and he agreed a very annoying sound. He touched the other end of the jumper wire to the power outlet, and instantly, the sound was gone. He could toggle the sound on/off by touching/removing the ground to the power outlet.
On the way back to the shop, I pointed out a critical section of the TSB for out of warranty cars (we bought ours in Feb 2005, and it has 49,000 miles on it): “Any repair performed after warranty expiration may be eligible for goodwill consideration by the District Parts and Service Manager or your Zone Office. You must request consideration and get a decision, before starting work.”
He called someone on his cell phone and got approval for “goodwill consideration,” meaning that the $300 part cost will be covered by Honda. I did not think to ask about labor, but I’ll let the list know what happens when I get the ANC job done next week. The tech thanked me for the homework I’d done. “You made my job easy,” he said.
Thanks again to those who reported this issue earlier and provided the TSB information. I can’t imagine being the first one in a dealership, no TSB backup, out of warranty, and trying to get the booming diagnosed without the jumper recipe.