Factory door subwoofer playing up

[shywaz]

Hi Fam,

Fighting another gremlin in my '05 Mustang GT.
When I bought it, it had an Android headunit upgrade already installed. Just a headunit, speakers being left OEM.
Since it originally had Shaker 500 system, I know Subwoofers must be in the front doors, but I can hear only high notes comming from there.

Took a look at the headunit wires - Subs were left unconnected by the previous installer, hence they didn't work.
So I've connected them according to this wiring schematic (connector J4, pins 1 and 2) - they started to work, BUT...
All is OK with the passenger speaker, but the driver's side speaker - it hums even if you take out the key and lock the car....
If I unplug the wires and leave them unconnected (like it was when I bought the car) all is ok, no extra sounds coming from it.

Is this the common problem with these cars? Or where should I start looking for a fix?

 

[Autokyrios]

Give Crutchfield a call and grab the correct OEM-to-aftermarket connector. Will save you miles of headaches and it's like $10.

The front subs are in the lower front doors. The amps for the front subs are behind the dash on the left and right (if you stick your head up under the dash on the drivers side you'll easily see it).

New head unit should be wired to the OEM cables which will rectify all your wiring mysteries (again, get the connector).

 

[Autokyrios]

Metra 70-5521
It's now $14.

 

[shywaz]

Metra 70-5521
It's now $14.

Since im in Europe, calling Crutchfield may not be the best thing to do

There is a metra kit already in it...

 

[Autokyrios]

Sorry, didn't know you were overseas. Might still give you advice, though. I think they also sell through Amazon, but there's other sound-system vendors in Europe.

If it actually has the correct metra kit in it, and it was put in correctly, you probably wouldn't have this issue. That's the kit I use on mine.
If one side is humming all the time, there's something botched in the wiring. Bad ground, improperly connected wire, etc.
Whoever originally did the wiring obviously didn't do a correct job, so I'd count the whole harness as sus.

An inspection of the speaker wiring in the doors may be of use unless you trust they didn't mess around in there. Try tracing the side amp wires back to the connector. I'll see if I can pull up the wiring diagram.

Buzzing is not normal. The system should be quite. Only common problem I know of is amplifier popping (you'd hear a speaker 'pop' when switching on/off the car) when people change head units, but it isn't consistent (I didn't have the problem).

 

[shywaz]

Previously my car got SJB issues, found two microcontrollers burned out.

If the water can enter SJB, maybe it also can do the same at the other side of the car? Hence driver side SUB/AMP not working properly.

Im guessing something might be not ok with the amp, as wiring at the headunit seems normal - there is nothing wrong to be made, just plug n play with the metra kit.

Do you know where the signal splits into left and right side amps? As there is only mono exit at the headunit.
Or do you have AMP wiring schematics?

 

[Autokyrios]

There was a TSB for the SJB water issue. Haven't heard of it happening elsewhere. Specifically had to do with the firewall pass-through related to the SJB, which doesn't exist on the other side.

I'll grab my wiring manual and see about grabbing a snap of the diagram(s).

 

[Autokyrios]

 

[shywaz]

Thanks!!!
Hopefully I'll get it sorted

 

[Autokyrios]

I'm still gonna say ping Crutchfield, even though they don't ship (themselves) outside NA. Only because I have experience with them. I remember when I did my first stereo swap in the car years ago, they had a guide, in addition to what Metra had. Depending on what your new head unit is, they may have support as well.

 

[shywaz]

Finaly i've sorted it!
Dont know if this is common, but connector pins were broken inside amps, (two of them even popped out while disconnecting) so i've just soldered them back, and all humming went away.
PS. My both amps are on drivers side, not on different sides

PPS. Now i get loud pop on headunit start, is there any adjustment options in the Android, to get it sorted?

 

[Autokyrios]

Figured it was a bad connection somewhere. Wonder if whoever did the original work yanked on the wires too much.
I thought the amps for the door subs were on each side. Guess my memories are bad. I could go verify since most of my interior is out (would be interesting to know if Ford has different configurations).

 

[XJCasper]

I have alwaysnl gotten a pop when starting my Mustang. It had a Alpine when we picked it up. Was having issues, so immediately replaced it. I just thought the pop was normal and had something to do with the remote wire and amplifiers.

 

[Autokyrios]

Axxess AXFD-5V Amplifier Interface - $20
Fixes the amplifier pop with some aftermarket heads and factory amps.

 

[shywaz]

Axxess AXFD-5V Amplifier Interface - $20
Fixes the amplifier pop with some aftermarket heads and factory amps.

Installed voltage stepdown from 12v to 5v and pop is gone!! Thanks Autokyrios!