Start with what is installed
Factory System Overview
For many installations, retaining the factory receiver while upgrading speakers and adding correctly integrated amplification is the more practical starting point. The Sony system adds several locations and an amplified subwoofer that need their own planning.
The basic system uses an AM/FM/CD receiver and six speakers. A six-disc receiver with satellite radio was another option, and the Sony 12-speaker package adds a subwoofer and two amplifiers. A Sony CD/DVD/navigation receiver was also offered.
SYNC, USB and auxiliary inputs, and a rear entertainment system with headrest screens can affect the intended upgrade. List the functions you want to retain and confirm the interface support for the exact original equipment.
Planning guide, not a fitment guarantee. Exact wiring, impedance, adapters, fasteners and removal procedures must match your vehicle. Photographs show selected configurations, not universal fitment.
Radio Upgrade
The climate controls are integrated with the factory receiver assembly. A conventional aftermarket conversion uses an adapter, relocates the climate controls and requires minor dashboard modification. That approach prevents straightforward reinstallation of the stock radio and is best planned with an experienced installer.
Some navigation-equipped vehicles may qualify for a dedicated direct-replacement screen/receiver package that avoids the conventional cutting and climate-control relocation. Verify an exact compatible package for the installed navigation system before treating this as an option; it does not apply automatically to every Flex.
Keeping the factory radio does not prevent a speaker or amplifier upgrade. Select integration hardware around the signals available from the particular base or Sony system rather than assuming all factory channels carry full-range audio.
Radio access and installation
- Identify whether the vehicle has the base or navigation receiver, Sony amplification, SYNC and rear entertainment.
- Decide between retaining the original receiver, a verified direct-replacement package, or a professionally planned conventional conversion.
- Confirm climate-control operation, interface requirements and every retained feature before beginning any irreversible work.
- After installation, test climate controls, all audio channels and each retained factory feature before closing the dashboard.
Check before reassembly
Test the receiver and every speaker channel before refitting trim. Confirm nearby switches, climate controls and vents remain accessible. Keep connectors secure and wiring clear of sharp edges, pedals and moving mechanisms.
Speaker Upgrades
Choose speakers by location and exact factory configuration, not the nominal diameter alone. Check mounting depth, screw pattern, grille clearance and electrical compatibility before ordering.
Front door woofers
Factory speaker size: 6x8-inch
The front-door woofers sit behind the removable door trim. Selected same-size replacements fit the original format, while smaller 5.25-inch units require mounting brackets.
- Uncover and remove the 10mm screws behind the release handle and pull handle. Remove the rear-edge Phillips screw, the screw under the reflector, and the screws along the front and bottom edges.
- Lift the panel, disconnect the wiring and release cable, then set the trim safely aside.
- Remove the four 1/4-inch speaker screws, disconnect the driver and fit the verified replacement.
Fitment and wiring notes
Check window movement and cable routing before restoring the panel. Confirm the replacement suits the factory or aftermarket amplifier being used.
Rear door speakers
Factory speaker size: 6x8-inch coaxial
The rear doors use coaxial speakers. They accept selected 6x8-inch replacements or bracket-mounted 5.25-inch units, subject to depth and electrical compatibility.
- Remove the covered 10mm handle screws, the Phillips screw under the reflector, and the front-edge and lower screws.
- Release the rear-edge clips, lift the trim and disconnect the harness and release cable.
- Remove four 1/4-inch speaker screws and disconnect the original speaker. Test the new driver before replacing the panel.
Fitment and wiring notes
Do not trap the release cable or speaker wiring behind the panel clips.
Center dash speaker — Sony 12-speaker system
Factory speaker size: 3.5-inch
The center driver is under a clipped grille. It is not part of every factory package, and its factory impedance is not established here. Secure spliced connections or appropriate wire connectors are needed rather than assuming a plug-in adapter exists.
- Release the grille’s five clips and lift it away.
- Remove the two 7mm speaker screws, unplug the original unit and fit the electrically compatible replacement.
Fitment and wiring notes
Verify impedance and available depth before selecting a nominally matching 3.5-inch speaker.
Front pillar tweeters
Factory speaker size: Factory tweeters; nominal replacement size requires verification
All versions have front pillar tweeters. The replacement must be custom-mounted to the trim, and its wiring must include the protection required by the chosen tweeter or component system.
- Move the door gasket away from the pillar, then release the trim clips starting at the top.
- Release the retainer, disconnect the harness and lift away the trim. Carefully release the original tweeter from its mount.
- Secure the new mount and connections, keeping all wiring and hardware clear of safety equipment and trim retainers.
Fitment and wiring notes
Do not interfere with pillar airbag components. Use the appropriate vehicle safety procedure before working around them.
Rear pillar speakers — Sony 12-speaker system
Factory speaker size: 3.5-inch, 8-ohm, wired in parallel
The rear pillar drivers are separate from the rear-door speakers. Their 8-ohm load and parallel wiring matter when choosing replacements; a lower-impedance pair can alter the load seen by the factory electronics.
- Open the lower screw covers and remove the 7mm screws.
- Release the upper trim clips, disconnect the harness and support the panel without pulling on the seat belt.
- Remove the two Torx T15 screws securing the speaker to the trim, then install the properly matched replacement with secure connections.
Fitment and wiring notes
Preserve seat-belt movement and trim retention. No matched wiring adapter is established for this location.
Shop Speaker Sizes
Browse the supported categories, then verify fit for your exact location.
Front door woofers
6x8-inch speakers5.25-inch speakers
Confirm the exact vehicle, mounting depth, impedance and any required brackets before ordering.
Rear door speakers
6x8-inch speakers5.25-inch speakers
Confirm the exact vehicle, mounting depth, impedance and any required brackets before ordering.
Center dash speaker — Sony 12-speaker system
Confirm the exact vehicle, mounting depth, impedance and any required brackets before ordering.
Front pillar tweeters
Confirm the exact vehicle, mounting depth, impedance and any required brackets before ordering.
Rear pillar speakers — Sony 12-speaker system
Confirm the exact vehicle, mounting depth, impedance and any required brackets before ordering.
A nominal size match does not establish direct fit. Preserve the configuration-specific cautions in this guide.
Tools and Installation Preparation
- Panel tool and small flat-blade screwdriver
- Phillips screwdriver
- Socket wrench and 7mm, 10mm and 1/4-inch sockets/extensions
- Torx T15 driver for rear pillar speakers
- For subwoofer access: 5mm and 8mm sockets in addition to the trim tools
Bass and Amplifier Planning
The Sony 12-speaker system has separate speaker and subwoofer amplifiers, with an 8-inch dual-voice-coil subwoofer in an enclosure behind the right rear cargo trim. Access is labor-intensive because the pillar trim, rear scuff plate, cargo-net hardware and side panel overlap.
The sub enclosure is secured to the body with three 10mm screws and two upper clips. After disconnecting it, the driver releases with eight front Phillips screws and an 8mm screw at the rear of the enclosure. Some replacement drivers require new mounting holes, so inspect clearance before drilling.
The supplied layout does not establish the original coil impedance. Check the chosen driver against the retained amplifier, or plan a properly integrated amplifier replacement rather than assuming any 8-inch dual-voice-coil subwoofer will work.
For a separate enclosure, preserve access to the third row and the cargo area you actually use. Measure the vehicle with the intended seating arrangement and secure the enclosure so it cannot move during braking.
Installation Checklist
- Identify base versus navigation radio and six-speaker versus Sony equipment.
- Choose a receiver strategy before modifying the dash.
- Confirm impedance and crossover requirements for each replacement speaker.
- Test audio, climate controls, doors and seat-belt operation before final reassembly.
Car audio guides, upgrades and installation planning.
