DIY - Installing aftermarket subs and amp [Archive] - Bimmerfest - BMW Forums

: DIY - Installing aftermarket subs and amp

02-25-2009, 03:49 PM
Hey guys, well i had found a useful tip on one of the threads. i thought i would post up how to install an aftermarket amplifier and subs using an MTX ReQ5. I purchased the MTX ReQ5from if anyone is wondering. it cost me $109 shipped.

I was going to install a 4 channel amp also but instead i just hooked up the ReQ5 to send a signal to my mono amp. first, locate the stock amplifier, mines is non logic7 and i found my amplifier on the driver side next to the navigation unit. i took out the carpeted wall on the driver side inside the trunk by removing the black clips on the floor. there is also a tie down that has a small cover on it, remove that cover and there will be two cross tip screws that you have to remove. you should be able to remove the wall after you have done that.

Next, remove 3 bolts that hold the bracket for the factory amp to the wall of the car. that should give you more room to pull it out and have more slack in the wires.

Next, locate the wires coming out of your amplifier. i ones i used to send the signal to the ReQ were the red with white strip as the positive and the brown and yellow stripe for the negative. those are the factory amp sub wires. The ones on the ReQ5 should be the two brown wires, one is a solid brown as the positive and the brown with black stripe as the negative.

Next, locate the white wire next to the two sub wires and use the yellow and red wires from the ReQ5 and tap into those. that wire will serve as a constant power wire. i couldnt find a switched source power wire but the power does shut off after a couple of minutes. so far so good with my battery not draining. The ground wire, i just used one of the bolts that hold the bracket to the wall as the ground and voila! your MTX ReQ5 should turn on after that. all you have to do is run your power wire and ground wire straight from the battery to your amplifier. another good thing about using the MTX ReQ5 is that it has a remote wire so you could hook up your amplifier and use that as a signal to turn the amp on. the RCA's are also ran from the MTX ReQ5. Deciding where you want to mount your amplifier is up to you. I Should have taken step by step pictures but i was so excited on doing this myself that i completely forgot.