Adding independent Level Control to Factory Bose Subwoofer (997-987)

By using our Bose Subwoofer Retention Harness you can accomplish one of two things.

  1. Keep the factory Bose subwoofer operational when adding an aftermarket amplifier for the other speakers in the audio system.
  2. Acquire subwoofer level control with an aftermarket radio. When adding a new radio with a fiberoptic adapter like the HUR module, the subwoofer will play but you will not have any way of adjusting it's level of output. Adding the retention harness will allow you to take advantage of the subwoofer settings and level control found in most modern radios. 

Bose Subwoofer

Removing the Subwoofer

Remove the plastic center cover from the air vent. It simply pulls off.

 Remove the center panel

This will expose a single Torx screw.

retaining screw

Pull the plastic cover off and unplug the power port.

Now remove the large Torx screw that fastens the subwoofer to the console.

Pull rearwards on the subwoofer enclosure. The whole assembly will now be free. Unplug the subwoofer harness and remove from the vehicle. 

Subwoofer Harness Note for Bose Equipped Vehicles

Bose equipped vehicles have a subwoofer with an internal amplifier. This amplifier can be made to work with your new aftermarket radio's subwoofer output (RCA) by adding an optional signal harness. This harness will send both audio signal as well as a turn on trigger signal to the subwoofers internal amplifier.

Optional Subwoofer Retention Harness

The subwoofer will operate as the manufacture intended even without this special harness, though the subwoofer level control on your new radio will not effect the subwoofer output. The advantage of using the optional subwoofer harness is that you will now have independant control of the subwoofer output relitave to the main volume. You can use this feature to make your audio system sound more or less aggressive. 

Connecting the Optional Subwoofer Retention Harness

Note: the connections described bellow show how the connections are made directly at the subwoofer in a Cabriolet or Cayman with the subwoofer on the passenger side of the console. However the same wires can also be found at the main amplifier in the trunk of '05-'08 vehicles and at the main amplifier under the passengers side seat in '09-''12 vehicles. The subwoofer signal travels from the main amplifier out to the subwoofer. Not from the radio to the subwoofer. The only reason why you would want to make these connections directly at the subwoofer in a Cayman or Cabriolet is because the subwoofer has to be pulled out to gain access to the radio anyway. In a 911 coupe it makes sense to make these connections at the main amplifier in stead of at the subwoofer because the subwoofer is located all of the way at the rear of the car. 

The harness has RCAs and a bullet connector on one end. This end will connect to your new radio. Connect the RCAs to the subwoofer outputs. Connect the Blue wire with the bullet connector to your radios Blue/White remote output wire.

The other end of this harness has three wires:

  • Blue - Remote out
  • Red - Audio signal +
  • Brown - Audio signal - 

Factory Subwoofer Harness

The factory subwoofer harness has 5 wires in it. The large gauge Red/Brown wire is 12 votls power. Leave this wire as is. The large Brown wire is 12 ground. Leave this wire as is. The White/Yellow wire is a 12 volt remote turn-on trigger wire. Cut this wire and permanently insulate the side that leads back to the vehicle. Connect the Blue wire from the subwoofer retention harness to this White/Yellow wire leading to the subwoofer. The two remaining wires are Orange and Orange/Brown. These are the audio signal wires. Cut and permanently insulate the side leading back to the vehicle. Connect the Orange/Brown wire (audio -) to the Brown wire of the subwoofer retention harness. Connect the Orange wire (Audio +) to the Red wire on the subwoofer retention harness.

That's It!

Now when the blue wire in the retention harness is energized the factory Bose subwoofer amplifier will turn on and receive audio signals via the RCAs.