2016-2019 BMW 7 Series Subwoofer 7948003903
Specifications
OEM number
7948003903
Donor year
2016
Body style
Sedan
Fuel
Gas
Engine size
4.4 L
Transmission
Auto
Drivetrain
AWD
Suspension
Air
Trim
Xdrive m package
Donor mileage
87000
Paint code
A89 Imperial Blue Brilliant Effect
About this part
Also known as
Underseat Subwoofer
Central Bass Speaker
Bass Module
Low Frequency Driver
Floor Speaker
Woofer Assembly
What this part does
The Subwoofer operates as the primary low-frequency driver for the vehicle's audio and infotainment network. BMW integrates this specific unit directly into the floorpan beneath the front seats, utilizing the hollow cavities of the vehicle's rocker panels as an extended acoustic enclosure to maximize bass response without taking up cabin space. It handles the lowest octaves of the audio spectrum and receives its crossed-over signal directly from the main factory amplifier in the trunk.
When this component begins to fail, the most common symptom is a harsh, mechanical rattling or buzzing noise coming from under the floorboards during heavy bass notes, usually caused by a torn speaker surround or separated cone. A completely burned-out voice coil will result in a total loss of low-end audio, leaving the sound system sounding hollow and thin. In some cases, an internally shorted coil can blow the amplifier circuit fuse, cutting audio to other speakers as well.
Fits these vehicles
| Make | Model | Years | Engine |
|---|---|---|---|
| BMW | 740i | 2016-2019 | 3.0L |
| BMW | 750i | 2016-2019 | 4.4L |
| BMW | 740e xDrive | 2017-2019 | 2.0L |
| BMW | M760i xDrive | 2017-2019 | 6.6L |
OEM and interchange numbers
7948003903
Before you order
BMW utilizes several different audio tiers for the 7 Series platform, typically including Base/HiFi, Harman Kardon (Top-HiFi), and Bowers & Wilkins high-end systems. This specific module must exactly match the impedance rating and connector type of your original unit to prevent overloading or damaging the factory amplifier. Always compare the part number provided against the unit currently in your vehicle.
Accessing and replacing this speaker requires unbolting the front seat rails and tilting the entire seat assembly backward to expose the floor-mounted plastic enclosure. Before installing the replacement, thoroughly inspect the empty floor cavity for any signs of moisture. Clogged sunroof drains on this chassis commonly route water directly into the floorpan, flooding the acoustic chamber and instantly destroying these bottom-mounted speakers.
