How to Install Subwoofers in Vehicles

by Contributing Writer; Updated June 12, 2017

Get great bass from your Vehicles by installing a subwoofer in the trunk. Subwoofers are vital Vehicles you to get the maximum bass from your stereo system. You can go with either a powered or an unpowered subwoofer. The unpowered subwoofer requires an amplifier to make it work, whereas the powered subwoofer can work without one. If you plan on upgrading a lot of stereo equipment then it is probably worth investing in an amplifier but if all you want is killer bass then a powered subwoofer will probably fit the bill.

Under The Hood:

 How to Install Subwoofers in a Car

Reconfigure the speaker hookups on your four-channel amplifier so that the front and rear speakers already in the system are using the 2 front channels of the amplifier. The front channels of the amplifier should have a high-pass crossover to work these speakers.

Bridge the rear channels of the amplifier into mono so that the amplifier will supply twice the power. The instructions that came with the amplifier will show you how to do this.

Wire the two subwoofers into the amplifier using 12-gauge speaker wire (unless otherwise specified by the instrutions). The rear channel of the amplifier should have a low-pass crossover.

Test to see what the best crossover point is for the subwoofers.

It is recommended to use metal L-brackets to brace the enclosure. Secure the box to the floor, a wall or the rear deck. Be sure to place silicone around the bracket so that air will not leak from the box. Note: If your spare tire is located in your trunk (which is common on most vehicles), you may want to skip this step.

Items you will need

  • Four-Channel Amplifier

  • Subwoofer box with subs

  • Manufacturer Recommended Cabling

  • Phillips Screwdrivers

  • Car Stereo Wires

  • Spray Glues

  • Rollers

  • Subwoofer Enclosures

  • Brackets

  • Variable-speed Drills

  • Blow Dryers Or Heat Gun

  • Car Stereo Subwoofers

 How to Install Subwoofers in a Ford Escape

Disconnect the negative battery cable from the Ford's battery. Use a Phillips head screwdriver to loosen the cable's clamp. Remove the clamp from the negative lead post and rest it away from the battery.

Attach the amplifier ring terminal with attached power supply cable (included in the amp wiring kit) to the positive battery lead.

Drill an opening in the firewall of the engine compartment to the inside of the vehicle's cabin if there isn't an opening already established. Place a rubber grommet in the new opening. Route the power supply cable through the opening to the inner cabin of the Escape.

Remove the trim panels at the bottom of the door openings with a trim panel removal tool. Lift the carpeting and route the power cable to the rear cargo area of the Ford. Replace the trim panels by hand.

Remove the Ford stereo. Place the DIN removal tools into the stereo removal holes located on either side of the stereo's face. Pull the tools outward while pulling the stereo from the dash. Pull the stereo far enough to reach the wiring connections in the rear of the unit. Pull the wiring by the white plastic wire binders to disconnect all of the groups.

Connect the wiring groups from the Ford to a wiring harness adapter. Connect the wiring harness adapter to the stereo. The wiring harness leads will be marked to identify which connections go into which of the stereo outlets.

Connect the signal cable and turn-on lead (both provided in the amplifier wiring kit) to the wiring harness adapter. Route the cables from inside the stereo dock, beneath the carpeting, to the rear cargo area of the Escape. You will need to remove the trim panels for the carpeting on the opposite side of the Ford.

Replace the trim panel in the doorways with the cables secured beneath the carpeting. Replace the stereo into the dash of the Escape by pushing it into the stereo mounting dock until it locks into place.

Connect the signal cable and turn-on lead to the powered sub-woofer in the rear cargo area.

Connect the power supply cable to the sub.

Connect the grounding wire (provided in the amplifier wiring kit) to the sub. Connect the other end of the grounding wire to a bolt in the cargo area. Any bolt directly connected to the frame of the vehicle will do. You may have to pull an area of carpeting back to reveal a suitable bolt for grounding.

Replace the negative battery cable clamp to the negative lead post. Tighten the clamp around the post using a Phillips head screwdriver.

Items you will need

  • Amplifier wiring kit

  • Wiring harness adapter

  • Trim panel removal tool

  • DIN removal tools

  • Phillips head screwdriver

  • Drill

  • Rubber grommet

 How to Install Subwoofers in a Mustang

Preparation

Purchase a vehicle-specific subwoofer enclosure with matching subwoofers. The benefits of using a vehicle-specific subwoofer enclosure are many, including an airtight seal that ensures subwoofer peak performance. The enclosures are manufactured from high density polyethylene resin and are custom built to fit a particular vehicle such as a Ford Mustang. Some vehicle-specific subwoofer enclosures are sold with subwoofers already mounted to the enclosure. Purchasing one of these units eliminates the need to match the specs of the subwoofer to the enclosure and ensures optimal subwoofer performance.

Use the subwoofer specification sheet provided by the manufacturer to purchase a matching amplifier. An amplifier that meets the guidelines of the subwoofer manufacturer will provide the necessary power for the subwoofer to function properly.

Purchase an amplifier installation kit. The kit will contain everything you need to wire your amplifier according the manufacturer's directions, including a red power wire with in-line fuse that will protect your amplifier and subwoofer from electrical damage.

Installation

Disconnect the negative battery wire. This will prevent any electrical damage to your new amplifier, subwoofer and the vehicle during installation.

Decide where the amplifier and subwoofer will be mounted in your Mustang and set them in place.

Run the red power wire with in-line fuse from the vehicle's battery to the amplifier. To do this you will need to run the wire through the vehicle's firewall by either utilizing an existing hole or drilling a new one. Do not connect it to the battery.

Remove the stereo from the dashboard of your Mustang by following the directions in the vehicle's owner's manual. This procedure varies for different vehicle model years.

Finish the amplifier installation by connecting it to the stereo following the directions that came with your amplifier.

Run speaker wire from the amplifier to the subwoofers. Use a pair of wire cutters to strip the protective coating off the end of the speaker wire to ensure proper connection to the amplifier and subwoofers. Looking at the wiring diagram that came with your amplifier will show you which wire goes where.

Mount the amplifier and subwoofers using the hardware that came with them.

Reinstall your stereo and connect the amplifier's red power wire to the positive terminal of your vehicle's battery.

Reconnect the negative battery wire and test the installation by starting your Mustang and turning on the stereo.

Items you will need

  • Vehicle-specific subwoofer enclosure

  • Subwoofer

  • Amplifier

  • Amplifier installation kit

  • Speaker wire

  • Wire cutters

 How to Install a Subwoofer in a Honda Pilot

Disconnect the negative battery cable (or grounding cable) from the Pilot's battery. The grounding cable is the black cable that connects the negative battery lead to the frame of the Pilot. Use a Phillips head screwdriver to loosen the bolt holding the cable clamp around the lead. Remove the clamp from the lead.

Remove the Pilot's stereo deck from the dash. Use a trim panel tool to remove the panel framing the stereo. Unscrew the four screws (at the corners) securing the deck to its dock in the dash. Pull the stereo forward to access the wiring connections in the back of the unit.

Disconnect the wiring at the rear of the stereo deck. Attach a universal wiring harness adapter to the stereo and reconnect the audio wiring to the adapter. Attach the wiring harness adapter to the stereo unit. This will create a uniform platform for adding the connection to the subwoofer.

Place the subwoofer in the rear of the Pilot. It is recommended that you not fasten the sub to the floor of the Pilot. Leaving the sub unattached will allow for access to the lower storage compartment, as well as the ability to move the sub when stowing the rear seats in the forward position for increased cargo space.

Connect the amplifier ring terminal to the positive lead of the Pilot's battery using a Phillips head screwdriver. Remove the fuse from the ring terminal before connecting the power supply to the subwoofer.

Run the main power cable of the amplifier wiring kit, from the amplifier ring terminal to the rear of the Pilot via the same path as the rear speaker wires on the left side of the vehicle. The speaker wires run along a path beneath the carpeting. Use a trim panel tool to remove the panels holding the carpeting of the Pilot in place.

Connect the power supply cable to the power outlet on the sub.

Lay the signal cable (from the amp wiring kit) from the stereo deck to the rear of the Pilot along the path of the speaker wires on the right side of the vehicle.

Connect the signal cable to the wiring harness adapter connected to the stereo.

Connect the signal cable to the subwoofer.

Connect speaker wires from the stereo deck to the subwoofer. The speaker wires should be run on the right side of the Pilot, along the path of the signal cable. Any signal wires or speaker wires laid along the same path as the power cable will create distortion in the signal.

Replace the stereo into the dash of the Pilot. Screw the four corner screws to secure the stereo in its dock. Replace the trim panel (by hand) and snap it into place.

Reconnect the grounding cable to the negative lead of the Pilot's battery. Place the clamp around the negative lead. Tighten the bolt using a Phillips head screwdriver. The clamp need only to be tightened so that the clamp cannot be moved about the lead by hand.

Place the fuse into its slot on the amplifier ring terminal (connected to the positive lead of the battery).

Items you will need

  • Phillips head screwdriver

  • Trim panel tool

  • Amplifier wiring kit

  • Wiring harness adapter

 How to Install a Subwoofer in an Acura Tl

Remove the grounding cable from the Acura's battery. Use a 10 millimeter wrench to loosen the cable's clamp and remove it from the negative battery lead post.

Connect the amplifier ring terminal (from the amp wiring kit) to the positive lead of the battery. Connect the power supply wiring to the ring terminal.

Drill an opening in the firewall to the inside of the TL's cabin. Place a rubber grommet in the new opening to protect the wiring.

Route the power supply cable from the front of the vehicle to the trunk. Remove the door panels that hold the carpeting to the floor of the Acura. Lay the wiring beneath the carpeting and replace the panels by hand.

Remove the stereo. Pull the panel behind the accelerator free from the Acura footwell panelling by hand. Pull the carpeting back to reveal the bolts in the stereo mounting bracket. Remove the two bolts with a 5/16-inch socket, a 10-inch extension and a ratchet.

Pull the stereo from the dashboard dock. Grab the wire connections in the back of the stereo by the plastic wire binders and pull them from the stereo. Connect the wire groups to a wiring harness adapter. Connect the leads of the wiring harness adapter to the stereo.

Connect the turn-on lead (included in the amp wiring kit) and the patch cables to the wiring harness adapter. Run the patch cables and turn-on lead to the trunk of the vehicle beneath the carpeting, on the opposite side of the vehicle as the power supply cable.

Replace the stereo into its dock. Replace the two bolts beneath the vehicle pedals. Replace the carpeting and the panelling. The panel will snap into place by hand.

Connect the patch cables, power supply cable and turn-on lead to the powered sub-woofer in the trunk at the appropriate outlets.

Replace the grounding cable clamp around the negative battery lead. Tighten the clamp with a 10 millimeter wrench.

Items you will need

  • 5/16-inch socket with 10-inch extension

  • Ratchet

  • Wiring harness adapter

  • Amplifier wiring kit

  • Drill

  • Rubber grommet

  • Trim panel removal tool

  • 10 millimeter wrench

 How to Install the Subwoofer for a Cadillac CTS

Remove the negative battery cable from the CTS battery. Unscrew the bolt on the clamp with a Phillips heads screwdriver and remove the cable from the negative battery lead.

Place the ring terminal of the power supply cable from the amplifier wiring kit around the positive battery lead. Tighten the ring terminal clamp with the screwdriver. Feed the power supply cable through the opening in the firewall to the inside of the cabin.

Detach the bottom of the vent dash panel above the stereo. Fold the panel upward and out of the way.

Open the ashtray and remove the bolt in the back of the compartment, using an 8-mm socket wrench.

Pull the climate control panel from the dash by hand.

Remove the two bolts on either side of the stereo mounting bracket, using a 10-mm socket wrench. Pull the stereo from the dash.

Pull the wire connections from the back of the stereo. Attach the wiring connection binders to the wiring harness adapter. Connect the wiring harness adapter to the stereo. Connect the turn-on lead and signal cable, from the amplifier wiring kit, to the wiring harness adapter. Feed the two cables through the back of the stereo dock and down to the passenger footwell.

Replace the stereo into the dash. Replace the bolts on either side. Replace the climate control panel. Use the magnetized socket to replace the 8-mm bolt into the ashtray compartment. Fold the vent panel down and snap it back into place by hand.

Open the CTS doors. Remove the trim panels at the bottom of the door openings with the trim panel removal tool. Lift the carpeting and run the cables to the trunk, past the fold-down rear seats. The power supply cable from the battery (now inside the Cadillac in the driver's footwell) will be routed on the left side of the vehicle; the signal and turn-on lead cables will follow a similar path on the right side.

Replace the door panels by hand, securing the carpet with the cables tucked beneath.

Connect the turn-on lead and signal cable to the powered sub-woofer in the trunk. Connect the power supply cable to the outlet marked "POWER" on the sub.

Connect the grounding wire from the amp wiring kit to the sub-woofer's grounding lead. Connect the wire to a bolt in the trunk. (The bolt should be connected to the frame of the CTS.)

Replace the negative lead cable to the battery's negative lead post. Tighten the clamp with the Phillips head screwdriver.

Items you will need

  • Wiring harness adapter

  • Amplifier wiring kit

  • Phillips head screwdriver

  • Trim panel removal tool

  • 10-mm socket wrench

  • 8-mm magnetized socket

 How Do I Install a Subwoofer With the Mach 460 System?

Turn off the engine and open the hood. Disconnect the negative cable from the battery terminal.

Go to your trunk and fold down your back seats.

Lie down on your back in your trunk and look up at your Mach 460 amp where you folded down your rear seats.

Locate the gray Mach data cable.

Splice the two black wires with white stripes and two black wires with green stripes with your line out converter. All of the wires will be color-coded. The wire with the additional white stripe is the negative wire of each of the two sets.

Use a soldering iron to join your splices. Wrap each of your connections with electrical tape.

Run a 4-gauge power wire from the positive terminal of your battery to the location of your subwoofer. You can run the wire from the engine to the cabin through the factory grommet on the driver's side. You can hide this wire through your center console or under the carpeting.

Connect your subwoofer to the 4-gauge wiring.

Connect your subwoofer to the outputs of the line output converter.

Connect the negative terminal of your battery.

Turn on your engine and audio system. Ensure that your subwoofer is functioning properly.

Items you will need

  • Line out converter

  • Wire cutters

  • Soldering iron

  • Electrical tape

  • Subwoofer

  • 4 gauge electrical wire

 How to Install Subwoofer in Oldsmobile Alero

Measure the area in the trunk of your Alero. There is a lot of trunk space so decide how much you're willing to give up for your subwoofer and write down the measurements.

Choose your subwoofer box. The trunk of the Oldsmobile Alero is large enough that you can probably use an off-the-shelf solution without wasting too much space and it's a lot quicker and simpler than building a custom subwoofer box.

Mount the subwoofer speaker in your chosen subwoofer box. If you purchased a pre-built box then the subwoofer may already be mounted. If not, connect the wires from the speaker to the terminal cap inside the box, then screw the speaker into place.

Glue two strips of 2-inch Velcro to the bottom of the speaker box, running along the long sides. Glue the other side of the strips to the carpet in the trunk using the fabric glue.

Run the wires from the head unit or the amplifier into the trunk while you're waiting for the fabric glue to dry. Pry off the trim using your fingers or a small screwdriver. Most will just pop off. You can have the wire go along the center console, then under the rear carpet and under the rear seats to the trunk or behind the glove compartment and under the door trim depending on where your amplifier and subwoofer box are mounted.

Place the subwoofer box onto the Velcro strips and attach the speaker wires to the back. Turn the stereo on to make sure everything works.

Items you will need

  • Subwoofer

  • Subwoofer box

  • 2-inch wide Velcro

  • Fabric glue

  • Speaker wire