Mercedes-Benz GLA Forum banner
21 - 33 of 33 Posts

·
Registered
Joined
·
156 Posts
Hi Mercedes.AMG,
Is it possible to post picture/s of the wiring signal you tee'd with HK Amps under trunk please.
Thanks
Ceasar
Sorry for not getting this done, I've recently had elbow surgery, so lifting all the stuff out the boot is not happening. I have to get a full size wheel out and a subwoofer, both too much for the one good arm.
 

·
Registered
Joined
·
156 Posts
Arm is better so I have took pictures.

The way I have done this then, I've "T" eed into the four wires that connect to top of HK sub. It uses a chunky 4 pin connector that has the 4 wires covered in cloth tape that needs unwrapping.

I cut the 4 wires and soldered me "T" connections, heat shrunk and covered in rubber black tape.

I then put "bullet" connectors on my 4 new wires about 8" away from the Tee. This is to make an easy disconnection point when you sell car, you can see I've put some loose heatshrink over the four connectors.

I have now sold my car so pic3 shows the bullet connectors "capped" off and its ready to be tucked back under the trim now that my Pioneer sub has been removed.

The HK sub has 4 wires because it uses a duel coil speaker, this was great for me as the Pioneer sub needs TWO high level inputs because it has two seperate amps & speakers in it.

You should not join these 2 pairs together, if you only want one input then only "T" into one pair of the HK subs connectors.

The rear 12V socket is capable of running up to 15A, I had a 10A fuse on the sub and it never blew, even flat out playing Dub Reggae. I would stick to the 10A limit as all the 12V sockets share the same vehicle fuse.

What I have not got anymore is the colours of the 4 wires in the HK sub plug but I do believe is was pretty obvious to determine what the two pairs are. It dont matter about the polarity as such so long as the two pairs are the same "if you use both", subs have a phase switch anyhow.

I hope you find this helpfull?
 

Attachments

·
Registered
Joined
·
156 Posts
If you look at Pic1 you can see the 4 wires of the car loom, to the right of the "T" point.

You can also note that it consists of a twisted pair or Brown and a twisted pair of Blues.

The two blues feed one speaker coil, the browns the other, they have the same signal in each.


Of course, I now have to install this sub in my next car also, that'll be the 4th time I've fitted this one, but I don't think the next car has the "built in" subs in the boot, so that'll make it fun.

The GLA was the easiest install "so far"
 

·
Registered
Joined
·
156 Posts
I have installed my active sub woofer and very happy with the result.
Big Thanks to Mercedes .AMG unfortunately he's not with us anymore I think.
Its a JBL Bass Pro SL 8 inch 250 watts Compact Subwoofer.
Cheers

Still here. You done a nice job there and I'm glad you sussed it out. I hope it puts the bass lines back.

I've got the diagrams for the GLC and it has the Burmeister amp in the boot floor, so I'll just "tap" into the speaker feeds to its subwoofers, unless it don't need it?

Reg. the power, I just used the 12V socket with a plug. I had to make it easily removable just in case I needed to make space in trunk/boot.
 

·
Registered
2020 MB GLA250 4MATIC Avantgarde Edition
Joined
·
26 Posts
Correction: JL now calls this product "Fix" and may require installing a volume knob up front. The MoBridge solution preserves the factory volume controls.
Is the DA3 necessary for the base audio system without Sirius XM? to my knowledge, there is no subwoofer or XM antenna/wiring present in the car unless they are optioned in. Most importantly, will this alleviate the need to splice into factory wiring to power an aftermarket audio system? I am still under warranty until 2025 and I cannot risk any permanent modifications.
 
21 - 33 of 33 Posts
Top