Crux's SOOFD-27 interface ensures that you can keep the factory speaker system in your Ford, Lincoln, or Mercury vehicle when you replace the factory radio. Connect the wires from this interface to the wires on the new stereo's wiring harness, and your power, ground, and factory speaker connections are covered. If your audio system has a factory amp and sub, the Crux interface can also keep them working too. The Crux interface lets you keep your car's auxiliary input active as well, but you'll have to choose a new car stereo with a rear aux input, as the Crux adapter's RCA connectors plug into that rear input.
The SOOFD-27 interface also offers the parking brake, reverse, mute, and Vehicle Speed Sensor (V.S.S.) outputs that you'll need if you're installing a navigation receiver. If you like your radio to keep playing after your vehicle is turned off, this interface also supports Retained Accessory Power (RAP) which keeps the music going until the door is opened.
Important Installation Notes
The SOOFD-27 interface is not compatible with factory SONY systems or the THX amplified systems. If you're keeping your factory sub, you'll need to choose a car stereo with a dedicated sub preamp output (full-range preamp outputs will not work). If you're keeping your vehicle's aux input, you'll want to choose a car stereo with a rear aux input, preferably RCA inputs that the SOOFD-27's RCA connectors can plug into.