GROM Ipod adapter - throttle interference?

[scriss]

Just installed a Grom Ipod Adapter (v3) in my E39 with the connection in the dash (rather than in the trunk). It uses posi-taps to tap into the battery pos, ground, and the bus wires.

I am getting a high pitched whine that matches the RPMs of the engine, like a slide whistle! The pitch gets higher as the RPMs increase, and then goes down as the RPMs decrease. :confused

It's not actually the throttle that the noise responds to, because the whine changes with the gear changes, not whether I am giving it gas.

Thoughts?

[hotseatenthused]

Are you useing the simple aux adapter/interface kit or the usb interface kit?

Also, have you emailed Grom tech support about this issue?

Grom tech support: "GromAudio" info@gromaudio.com

[scriss]

I'm using the aux adapter, not the usb version.

Yes, I e-mailed them, and we are in the process of troubleshooting it. I just thought I'd throw it out here in case anyone here has had the issue.

[NegativeCamber]

Just installed a Grom Ipod Adapter (v3) in my E39 with the connection in the dash (rather than in the trunk). It uses posi-taps to tap into the battery pos, ground, and the bus wires.

I am getting a high pitched whine that matches the RPMs of the engine, like a slide whistle! The pitch gets higher as the RPMs increase, and then goes down as the RPMs decrease. :confused

It's not actually the throttle that the noise responds to, because the whine changes with the gear changes, not whether I am giving it gas.

Thoughts?

i had the same problem with my usb kit. the problem is both the power and ground source. i tapped onto the cig lighter wires and fused it. problem solved. this is what happened: after following their directions, i immediately got the noise. when i tried grounding the unit to the battery (while still tapping 12v from the radio), the noise was reduced, but still very audible. when i took 12v from the cig lighter (while still grounded at the battery), it was gone. apparently not all cars have this problem but they are not aware of it. i might bring it up to them.

[hotseatenthused]

i had the same problem with my usb kit. the problem is both the power and ground source. i tapped onto the cig lighter wires and fused it. problem solved. when i tried grounding the unit to the battery, the noise was reduced, but still very audible. when i took 12v from the cig lighter, it was gone. apparently not all cars have this problem but they are not aware of it. i might bring it up to them.

As regards " i tapped onto the cig lighter wires and fused it."

Did you put the fuse pre or post tap? In other words did you connected to a fused cig lighter wire or connect to same and then add a fuse to the power wire going to the Grom? What amp fuse(s)? Please excuse my ignorance but electrical isn't my strong suit. Maybe you could write up a nice little DYI fix for this .... Mystery whines in audio are not altogether uncommon.

[NegativeCamber]

As regards " i tapped onto the cig lighter wires and fused it."

Did you put the fuse pre or post tap? In other words did you connected to a fused cig lighter wire or connect to same and then add a fuse to the power wire going to the Grom? What amp fuse(s)? Please excuse my ignorance but electrical isn't my strong suit. Maybe you could write up a nice little DYI fix for this .... Mystery whines in audio are not altogether uncommon.

i edited my post to make it a bit more clear on the procedure i did to narrow down the source of the noise. i put my own 5 amp fuse in between the power wire going to the grom unit and the tapped 12v wire to the lighter. i should of done a quick write up, but i wasn't too sure if this was even a common problem. apparently when you tap onto the power and ground wires at the back of the radio, you pick up the noise in one of those wires or possibly both. i'd experiment with temporary wire extensions to the battery and see which wire gets rid of the noise.

[hotseatenthused]

Thanks. That’s much clearer and this must be helpful to the fellow currently troubleshooting this issue.
It’s interesting to note that this issue presents in both the basic unit and the USB unit.
I am trying to ascertain the difference between the two units. Also I’m wondering if the USB unit also has the 3.3 stereo mini-jack and whether these can both be used, together or separately. The marketing material is not very specific in this area.

[scriss]

Grom asked that I send the unit back to them so they can test it. I'll include this thread so they can se NC's comments and solution.

[fun2drive]

I sent my Grom unit back because audio output (CD-43 E36 M3 Radio) was very weak or non-exsisent. One thing that I plan to do once I get the unit back and get audio output is to re-tap the radio power to a switched 12V source. I am guessing you are tapping the always on 12VDC wire to the radio?

Picking up alternator whine is not that uncommon.
Interested to hear how you solve your noise coupling...

[hotseatenthused]

Did you get it back yet?
Did re-taping the radio power to a switched 12v source solve the issue?
What about NC's comments and solution?
Could you possibly post or IM me the guy's name at Grom you are dealing with?

As soon as the weather clears I plan on attempting to ad an aux input, but I'm not looking forward to the headaches and would like to avoid in as much as possible.

[fun2drive]

GROM updated my system to a Ipod V3 system. I have no improvement in function. Verified all positaps are making connection, the CD adapter is inserted correctly and no function what so ever.

I have corresponded with Alisher for warranty and function and Helen is the person that sent my unit back.
I fear that there are unknown differences in the CD43 radio which is causing this.

Connor and I have corresponded and he has the same radio, same harness, same wiring approach except he didn't use positap he directly tapped them, CD adaptor installed the same and his functions mine would go to Disc 1 now it refuses to even recognize the CD adaptor since it shows "No Disc" ever time the CD button is pressed.

I have tried Iphone and Ipod makes no difference...

I have no alternator noise because the car has never been started and of course the Grom unit does not work so it matters not.

I really hope I can get this working because I hate the hack look of any radio except a BMW one but my patience is waning and I might just go to another non BMW radio with USB and aux plug.

My radio is perfect so it is not the radio but could be some unknown to me radio software differences...

[msujay]

I just received my V3 with Bluetooth and have it installed in the trunk. much easier install, but I am also getting the engine interference. I am waiting on an email back from Grom. Anyone know if I could just try and ground it to the battery?
As a side note to anyone deciding on the head unit or trunk install kit. The trunk install kit isn't long enough to allow the iPod cable to reach the console!

[wohast]

did anyone figure out a solution a solution to this problem? i just had a Grom BT3 installed, and i get the hiss very bad when streaming music. Heres a video i recorded that i am sending grom tonight:



the hiss drives me crazy when on the freeway...

i have a 2003 z4 3.0i with DSP amp in trunk, no navigation, and no cd changer.