We are in the heart of the winter here in Eastern Canada. With the Jeep sleeping in the garage I decided to get around to installing the small subwoofer I have had on the shelf downstairs for a while.
This is to show a very basic install of a compact powered subwoofer. My stereo system is completely stock, so this is just to add to it. Obviously, this would be better with an upgraded head-unit and speakers which I will probably add eventually. For now, it is just to upgrade the factory system and take some of the heavy bass off of the speakers. In turn, this will make the whole system sound better.
Subwoofer used is a Euphoria EPS68 6×8″ Low Profile Powered Subwoofer / 500W -
(I purchased this used from a friend)
https://euphoriacaraudio.com/product/eps68/
Line converter used -
https://www.amazon.ca/dp/B00LIAHSM4/?tag=tjforum-20
Supplies used -
- 8 gauge wire (red) for power
- 16 gauge wire (black) for remote
- 1/2 and 3/4" black wire protector
- Heat shrink
- Electrical tape
- Zip ties
-8 gauge ring terminals for battery and ground wire
- 8 gauge in-line fuse (waterproof)
- Rosin core solder
- Self stripping tap connectors (18-22awg)
The first part of the harness runs from the battery itself to the subwoofer. I chose 8awg wire for this size subwoofer. An 8awg ring terminal was used to attach the power wire to the postive (+) battery terminal. This ring terminal was soldered and protected with heat shrink. In-line fuse was installed right after the battery terminal. I would recommend a water proof style fuse holder here as this is in the engine bay. I chose a 30amp fuse for this. Remember, you are fusing based on wire size and the 8 gauge wire would be safe with a higher fuse size, but a prefer to go on the lower end and upgrade fuses if it happens to be too light. This main power wire was wrapped in wire protector and ran along the firewall on top of the factory engine wiring loom. I zip tied it in place and it looks OEM as it can to me. It travels into the cabin via the rubber firewall grommet the main engine loom uses. At this point, the wire comes into the cabin, tucks under the door sill in the factory wiring harness holder, and is hidden under the drivers rear carpet. The other end of the wire is soldered to the correct pin out on the subwoofer harness connector. (Refer to the proper pin outs for your subwoofer / amp). The soldered joint is protected with heat shrink. Tape is acceptable here as well.
At this point it was time to install the line converter. I will not include steps on how to remove the factory stereo from a TJ. Plenty of articles on the internet are available with a quick Google search. This basic converter simply taps into your rear speaker wires and converters to a RCA signal you can plug into the subwoofer.
*If you have a aftermarket head unit you can still follow this guide, just skip this step and go ahead and plug your RCA cables into the head unit.*
Refer to your specific factory head unit wiring diagrams to figure out which wires are right rear +, right rear - , left rear + and left rear -
Simply use the T-tap connectors to tap into your four rear speaker wires and connect the four wires on the line converter. They are color coded and the converter instructions will include this.
Connect T-tap's to both the constant power wire on the head unit, and the ground wire. If the constant power is not yellow, use a multi meter or test light to figure out which pin in the connector is given constant battery power. The ground is black.
The line converter will also have a remote wire stemming from it. Run this wire along with your harness to the subwoofer. Your subwoofer harness will have a pin for this. This wire tells the subwoofer to power on and off when the head unit gets power or the speakers receive a signal.
The line converter features a volume adjustment knob. For now I just left this under the dash but you can chose to mount it under the dash if you want. I plan to run this under the center console and hide it in the storage armrest.
Tap connectors installed - again if you have a aftermarket head unit with RCA outputs, you won't need this.
You will now need to hook up your RCA cables and run them along with your power and remote wires to the subwoofer. This delivers audio to the subwoofer. You can now place the headunit back into the dash and secure it.
Now, I loomed together the power, remote, and the audio cables with small zip ties and wrapped them with larger wire protector. Wires are run from under the dash, along the factory wiring loom under the door sill, under the drivers side carpet along the rear fender well, and out of the carpet as pictured below.
The final step is to connect a ground wire for the subwoofer. I chose to remove one of the rear seat brackets, grind off some paint on the bracket, and connect the 8 gauge ground wire with a ring terminal (same as the front battery connection) to the seat bracket bolt. Be sure to retighen this bracket bolt to factory spec for safety reasons.
Your subwoofer is now installed. You will find this is a nice addition to any factory stereo regardless of how powerful the system is. I choose to use a low profile powered unit in my Jeep as it is hidden under the seat for security purposes and also to not lose the already minimal trunk space the TJ has!