Install an after-market head unit in the 2008–up
Impreza / WRX / STi / OBS, 2012–up Crosstrek, and 2009–up
Forester (without OEM Kenwood, TomTom, or Fujitsu Ten navigation), and
many 2010–up Legacy / Liberty / Outback (any car where Metra
70-7552 or Scosche NN04B fits).
Retain use of your car's audio Steering Wheel Controls
(interface adapter module required for most head units).
Legacy and Outback models with
harman/kardon speaker/amp system
ask me about this version (like Metra 70-7553 and Scosche NN05B)
Note: If you want to keep your factory head unit and add
a subwoofer, speaker amplifier, Line Output Converter (LOC), audio
processor, gauges, phone car kit — any application where you need
to tap off or connect between wires on the radio harness — see this combined 20-pin forward/reverse harness.
You do not
need the combined harness when switching to an aftermarket HU.
For older model years and 2008–up Imprezas and
Foresters with OEM Kenwood or TomTom navigation, please see this 14-pin wiring adapter.
Ask me about my 24-pin secondary harness to retain your SWCs, aux, etc.
None of the other after-market harness manufacturers
include the wires for the Audio Steering Wheel Controls (SWCs).
Some have even omitted the ground, power antenna, and illumination
wires. My harness avoids needing to tap into factory wires (the
reason you use this kind of harness in the first place).
Features on my 20-pin harness:
- EIA-standard color-coding (same as other after-market
harnesses and HUs)
- Printed labels (for example, "LEFT FRONT POSITIVE")
- Pre-stripped ends ready for you to crimp or solder to the
harness that comes with your new radio
- All harnesses include these 16 wires:
- Four speakers (8 wires)
- +12 Volt Accessory (key-switched)
- +12 Volt Memory/Battery (always-on)
- Power antenna control (remote turn-on for antenna booster
amplifier or motorized antenna)
- Illumination ("Illumination +") — used for dimming
on many aftermarket HUs
- Audio Steering Wheel Controls (3 wires)
Ask me about adding these additional wires (for special cases):
- CAN data bus (2 wires)
- Illumination (–) for custom lighting projects (Note:
aftermarket HUs do NOT need
this — use the "Illumination +" wire that I include standard)
- VSS (Vehicle Speed Signal) — only present on the
factory harness on 2012–up Impreza and Crosstrek, 2014–up
Forester, and 2015 WRX/STi models. Older Impreza, WRX, STi, and
Forester models do NOT have
this. Only some aftermarket navigation HUs need this signal.
See my Subaru
20-pin pin-out table for more information about the factory wires.
$12 (with 3 SWC wires)
Also available: Axxess ASWC steering wheel
See this page for more info.