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PAC AMP-GM21B Pontiac Factory Integration Adapter
Required with OS-1 Bose Interface for 1999-02 Pontiac Grand Prix to retain OnStar® and Bose® systems
Our take on the PAC AMP-GM21B Pontiac Factory Integration Adapter by Crutchfield's Robert Ferency-Viars
Pacific Accessory Corporation's GM21B harness works in conjunction with the OS-1 BOSE adapter to allow you to replace a GM radio (without RDS) in a 1999-02 Pontiac Grand Prix. You can install an aftermarket receiver, and still maintain operation of the OnStar® system and the GM Bose® amplifier and speakers. Warranty: 1 year.
Important Note: The GM21B harness and OS-1 BOSE adapter will only interface with 1999-02 Pontiac Grand Prix radios that do NOT have the "RDS" option. If there is an "RDS" logo on the radio face, the harness and adapter kit will not work. In order to determine compatibility with your vehicle, please use the vehicle selector on our site, or call a Sales Advisor at 1-888-955-6000.
Note: Most vehicles will require additional installation parts please identify your vehicle if you haven’t done so. You can also call an Advisor for more information.