PAC RP4.2-BM21

Radio Replacement Interface with built-in Steering Wheel Control Retention for Select BMW Vehicles

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This item has been discontinued

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Installation Note: Not compatible with vehicles equipped with the upper display screen (above radio) (CCC or CIC systems). This screen is not retained if the radio is removed, and the owner will lose the ability to adjust some vehicle settings. Radio replacement is not recommended for those applications.

Product Features:

  • Retains OEM steering wheel control functions (pre-programmed)
  • Data controlled 10 Amp accessory output
  • Provides vehicle speed signal (VSS), illumination, reverse and parking brake
  • Removes SOS error light from cluster after factory radio is removed
  • Data controlled outputs for connecting an aftermarket navigation radio
  • Single programmable 12v output
  • Easily configurable using a PC application
  • Highly visible tricolor LEDs to keep the user informed of the module’s status.
  • Retains factory amplifier (Non-Fiber-Optic)
  • Retains i-Drive control. Operates some features of the aftermarket radio (tuning, etc.)
  • Retains rear park assist and front collision detection
  • Direct USB updatable. PAC-UP NOT Required.
  • Also not compatible with the following:
    • Does not retain amplifiers equipped with a Fiber-Optic input
    • 1 Series equipped with navigation is not compatible
    • 2006 3 Series coupe is not compatible
  • Authorized Internet Dealer
  • 1-year Manufacturer's Warranty

Compatible Models

  • BMW
    • 2011 - 2014 1 Series
    • 2006 - 2015 3 Series/M3
    • 2010 - 2014 5 Series/M5
    • 2011 - 2014 6 Series

Check out the PAC RP4.2-BM21 Owner's Manual

Harness Features

Vehicle Sound System
This refers to what kind of sound system the vehicle has. Premium audio systems are generally name brand systems (such as JBL, Bose, Rockford Fosgate, etc) that have been installed inside a vehicle when it leaves the factory. Often they more advanced systems, complex wiring, factory amplifiers, and other features that can make installing aftermarket component difficult.
Standard and Premium Sound
Main Harness Function
Different installations on different vehicles require different harnesses. This type is what the harness is considered. Each wiring harness we sell serves a purpose such as installing an aftermarket car stereo, integrating an aftermarket amplifier with your factory car stereo, connecting Bluetooth to your factory car stereo, and more.
Connect/Install an Aftermarket Car Stereo
Compatible Vehicle Make
Allows you to view only items that are compatible with your vehicle's make. Does not guarantee that it will work with your vehicle year or model.
Compatible Vehicle Make and Model
The model of vehicle that this vehicle specific product is designed for. Please keep in mind that engine variations can affect the compatibility of the products.
BMW 1 Series
BMW 3 Series
BMW 5 Series
BMW 6 Series

Warranty and Return Policy

Parts Warranty Duration
1 year
Labor Warranty Duration
1 year
Warranty Provider

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Sonic Electronix Wiring Guide

Wiring Diagram Legend

Warning: The image depicted shows the resistance change when wiring multiple subwoofer terminals. Please refer to your subwoofer's owner's manual for the proper wiring of its terminals. Sonic Electronix, Inc. is not responsible for damage caused to your audio system or vehicle due to improper installation. Please call tech support at 1-877-289-7664 if you require additional assistance.

Product Name: PAC RP4.2-BM21

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PAC RP4.2-BM21

Radio Replacement Interface with built-in Steering Wheel Control Retention for Select BMW Vehicles


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