Big Green

Recently I've been noticing that when the HFL volume is above 20, there is a high pitched (but not piercing) feedback that is based on the RPM's of the car. I told my dealership who recently replaced the HFL about the issue, and he said he would look into it. Came back and told me about a TSB for modifying the ground wire, said it's all taken care of. Didn't have my phone on me, so I had to wait to check it out. Not taken care of. Any thoughts? Has anyone had this issue?

I'm new to Acura and new to this dealership, and don't want to step on toes as I've already gotten brand new brembo's, new HFL, and labor on making my switchblade key all comp'd (long story)...

PhilB81

Stupid question but is do you hear it during a phone conersation or when the device is waiting for voice prompts?

Big Green

If it's helpful it's not stupid! I only hear it during phone calls.

PhilB81

Mmm is your cellphone near your head unit? In my old car if I put my cell by the headunit it would buzz.

Another thing I noticed, is with my iPod setup (see sig follow link for details) but short story: it's using an apple cable to RCA then RCA to 3.5 mm into the aux Jack. Then I have a USB griffin charger on that apple cable. Here's the stupid part: I noticed that if I unplug my iPod or iPhone put the stereo on aux and turn it up a bit I get altenatoe feedback. As soon as I plug in an iPod or iPhone, without it playing any music just hook it to the conector, the buzzing goes away. Now I diet try HFL and no iPod connected but I'm wondering if your getting some feedback from ur aux, and if you have nothig hooked up to the aux, try disconnecting your sub. All of it, power ground and audio cables.
In my old 01 CL typeS I had to resort to 2 pairs of ground loop insulators I had an after market head navi headunit, a sub+amp, and still factory amp in the circuit. Not my smartest moves I eventually bypassed the factory amp and my buzzing went away...

I know this isn't your exact situation but it's something to consider. Sorry I'm not of more help

Big Green

Phil, thanks for the feeback, but I think it's a moot point now. I just was in the car, and realized that the feeback is during any HFL interaction, not just during a call. If HFL is on, and the volume is +20 or more, it's major feedback - high pitch - based on RPMs.

Will Y.

Are you by chance placing your phone in the console compartments below the radio/Navi unit? When I did that with Motorola cell phones, they would generate feedback during HFL use.

The feedback does not occur if my phone is placed in the rear cupholder, onto the cupholder cover, in the armrest compartment, in the door sunglass holder or is in my clothing.

PhilB81

I'll try to listen in my car if I have feedback, but did you try disconnecting your sub amp or isimple as stated above and see if you still hear it?
Also, tell us where you keep your phone during a call. I pit mine next to my wallet in the drivers door. Like I said in my old car my cell would give feedback to the unit if it was too close so I never put it close to the TLs headunit.

What phone do you have? A volume of 20+ is a bit high on the hfl, try cranking up the cellphone's Bluetooth volume, I did that on my iPhone and it's much more convenient. Before the hfl lady would yell at me then I could barelyhear the phone call.

Big Green

I always place the cell phone either in the cupholders or in the center console next to the arm rest. I have the bluetooth volume set on high on my iPhone 3G, and only run into the volume being above 20 during freeway drives and/or when talking to someone who is speaking quietly.

PhilB81

oh man, you hear the buzzing over highway noise, that's pretty loud...

ya other than unhooking ur iSimple and sub to see if it stops, i have no clue what to suggest.

Big Green

Just spoke to the dealership (they're not charging me, thank god) but basically she told me that I have a U0155 code that says "take your car to the dealership, please limit your driving" as well as the whine, which are both attributed to my amp drawing too much power and not being shielded. Now, I got both my iSimple and amp installed at Best Buy, but has anyone heard anything on this issue? I probably need to give Best Buy some direction here... I'm hoping you all can help!

PhilB81

maybe you need a capacitor installed for your amp, but a single 12 shouldn't draw that much, unless your pounding it pretty hard.
Try some Ground Loop Insulator maybe? Linky Best buy has Ground loop insulators too.

btw, i noticed in my car today a brief period of 'interferance' with my hfl. It happens when I place a call, right at the beginning before i hear the ringing noise.

Big Green

Best Buy said it might have something to do with the 'short wire'? and where they placed it. I'm now more concerned about the U0155 message from the engine than I am the noise... ever heard of this code error?