Aftermarket Headunit Installation for 2016-2022 Subaru Vehicles with Harman Kardon Audio

1An iDatalink Maestro module (RR or RR2) - required to keep the amp

An iDatalink Maestro interface module is the only way we know of to retain the Harman Kardon amplifier with an aftermarket headunit. It communicates with the amplifier, feeds it audio from your new headunit's front RCA outputs, and also retains your steering wheel controls - no separate steering wheel module is needed. Which module you need depends on the vehicle's amplifier generation. The standard Maestro RR covers the 2015-2017 Legacy and Outback, 2016-2018 Forester, 2016-2018 WRX/STI, 2015-2017 Crosstrek, and 2015-2016 Impreza. The newer Maestro RR2 is required for the 2018-2019 Legacy and Outback, 2019+ Forester (including the Forester Wilderness), 2019-2021 WRX/STI, 2018+ Crosstrek, 2017+ amplified Impreza, and the Ascent. (The RR2 also works in the older vehicles; the RR cannot be used in the newer ones.) The full year-by-year table is on the package listing.

We build the complete package per order: the Maestro module, the iDatalink Subaru vehicle harness, and custom plug-and-play wiring for your specific headunit's connector. We also program the module for your headunit before shipping (we will ask for the headunit's serial number). Build time is about a week. Order it here - pick your module and enter your headunit in the options:

Prefer to talk it through first? Email us with your model, year, and the headunit you are installing and we will confirm the exact setup.

2Choosing a headunit

Almost any aftermarket headunit can work with the Maestro module, but the experience differs:

-iDatalink-compatible units (many Pioneer, Sony, Alpine, and Kenwood models) give the best result - steering wheel controls and full sound adjustments, including front/rear fade, stay available on the headunit. Check your model on the iDatalink Maestro compatibility list.
-Budget Android units (ATOTO and similar) work too, but the front/rear fade gets fixed at a set level when we program the module - it cannot be adjusted from the headunit afterward.
-The headunit needs front RCA pre-outs to feed the Maestro. Most units have them; for the few that do not (the ATOTO A6PF, for example) a line output converter is required - ask us.

3Adapters that finish the job

You do NOT need the 28-pin backup camera harness or the direct wire harnesses from the standard 2016-2022 page - those functions are built into the custom Maestro wiring. You will still want these two:

USB retention harness - $22:

AM/FM antenna adapter - $19:

Optional: the Starlink bypass plug if you want to disconnect the factory telematics module while keeping the front speakers working.

4The alternative - amp bypass / replacing the amplifier

If you would rather remove the Harman Kardon amp entirely, keep in mind the factory system drives 8 amplified channels (front tweeters, front doors, rears, and subwoofer) and the speakers are low impedance (about 2 ohms). A headunit alone only powers 4 channels, so a straight bypass loses the subwoofer - a full replacement needs an aftermarket amplifier that is stable at 2 ohms. We sell mating connectors for the OEM amp plugs, with a full pinout, for this kind of build - email us for details.