Tools Needed

  1. Amplifier Harness
  2. Flathead Screwdriver or Interior Trim Removal Tools
  3. Posi-Twist Connectors or Soldering Iron/Solder

Harness Installation

This harness installation will cover the signal portion of an aftermarket audio upgrade. The installation does not include running power to an aftermarket amplifier, DSP, or subwoofer.

Accessing the OEM Amplifier

Remove the passenger side kick panel. There are plastic clips on the top & bottom holding it in place. It may be easier to remove the glove box and pull the panel up and towards the engine bay. Removing the clips will allow the kick panel to be removed without any force.

Plugging in the Harness

Insert the harness in the furthest left plug, between the female factory amplifier and male speaker inputs. The loose outputs on the harness can be connected to speaker wire. Running 9-wire or speed wire will drastically ease installation from the harness to aftermarket components.

The highlighted rectangle is the female amplifier output. The highlighted box below is the male speaker input. The posi-twist caps between the highlighted boxes are the harness’ loose wires connecting the speed wire of aftermarket components.

Honda Civic OEM Amplifier Diagram

Please see the diagram below for a translation to the harness*

Amplifier Harness Diagram

CavityTerminal NameOEM ColorHarness Color
A2SUB +WhiteYellow
A5FL Speaker +Light GreenWhite
A6FL Speaker –Light BlueGrey
A7RR Speaker –BrownGreen
A8RR Speaker +YellowPurple
A9RL Speaker –WhiteOrange
A10RL Speaker +BlueBlue
A11CTR Speaker +BluePink
A12FR Speaker –PurpleWhite/Black Stripe
A13FR Speaker +GreyGrey/Black Stripe
A14FL Tweeter +YellowGreen/Black Stripe
A15FL Tweeter –GreenPurple/Black Stripe
A16FR Tweeter +Light GreenOrange/Black Stripe
A17FR Tweeter –PinkBlue/Orange Stripe
A18CTR Speaker –WhitePink/Black Stripe
Highlighted the outputs I’d suggest for the full frequency band*


  • The harness installation is straightforward if power lines and aftermarket speaker lines have been run. The harnesses open wires will need to be connected to an aftermarket DSP, LOC, or high output accepting sub.
  • The wiring diagram above is for the 10th generation Honda Civic.
  • The Honda Accord and CR-V use different output diagrams than the Civic.
  • The 11th generation Civic uses a different diagram.
  • Posi-twist connectors are bulkier than soldering wires and may prevent the kick panel from closing without pressure.


Please reach out to [email protected] for questions or comments. There are plenty of general installation guides and videos but if there are enough requests I’ll make one for the civic.