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Cable Used to Connect Aftermarket Stereos To Factory Amplifiers In Select 1988-1998 GM Vehicles

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List price $13.99


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Harness Features:
  • Cable used to connect aftermarket stereos to factory amplifiers
  • Compatible with select 1988 - 1998 GM vehicles with Bose sound systems
    • Also Requires PAC OEM-1 for an easy upgrade of a factory "premium" sound system
  • 1-year Manufacturer's warranty
Compatibility List
  • Buick:
    • 1988-1994 Le Sabre Park Avenue
    • 1990-1995 Riviera
    • 1991-1996 Roadmaster
  • Cadillac:
    • 1988-1993 Coupe Deville
    • 1988-1991 Eldorado
    • 1988-1993 Fleetwood
    • 1988-1991 Seville
  • Chevrolet:
    • 1990-1997 Camaro
    • 1991-1996 Caprice
    • 1990-1996 Corvette
    • 1990-1998 Lumina
  • Oldsmobile:
    • 1988-1993 Toronado
  • Pontiac:
    • 1992-1998 Bonneville
    • 1990-1997 Firebird
  • Yellow 12V Constant
  • Red 12V Accessory
  • Black - Ground
  • Orange Dash Light Dimmer/Illumination
  • Green Left Rear Speaker (+)
  • Green with Black Stripe Left Rear Speaker (-)
  • White Left Front Speaker (+)
  • White with Black Stripe Left Front Speaker (-)
  • Purple Right Rear Speaker (+)
  • Purple with Black Stripe Right Rear Speaker (-)
  • Gray Right Front Speaker (+)
  • Gray with Black Stripe Right Front Speaker (-)

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.
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.
Install a Car Stereo & Bypass the Factory OEM Amplifier
Type of Harness
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.
Buick Lesabre
Buick Park Avenue
Buick Riviera
Buick Roadmaster
Cadillac Deville
Cadillac Eldorado
Cadillac Fleetwood
Cadillac Seville
Chevy Camaro
Chevy Caprice
Chevy Corvette
Chevy Lumina
Oldsmobile Toronado
Pontiac Bonneville
Pontiac Firebird

Premium Harness Features

Factory System Amplification
This refers to the factory sound system and whether the item is compatible with amplified or non-amplified systems.
On-Star Compatible
This means that the harness is compatible with vehicles that have On-Star built-in.
CAN-BUS Compatible
CANBUS Ballasts ensure compatibility with ALL vehicle makes and models without the need for additional accessories. In addition, they have built-in Anti-Flickering Capacitors to help prevent lighting issues caused by voltage spikes and drops by stabilizing the power.
GM-LAN Compatible
This means that the item is compatible with GM-LAN systems.
Compatible with Aftermarket Navigation Systems
This means that the item is made to work with aftermarket systems with navigation. Typically, this means that the harness has wires that are used with GPS navigation systems, such as VSS wires and others. Please read the product description for full details of this feature.
Chime Retention
This means that the harness is able to retain the vehicles chimes.

Warranty and Return Policy

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

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Rating Distribution

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Average Attribution Rating


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OEM-1 thumbnail


• Easily Upgrade A Factory 'Premium' System
• Plug And Play Installation
• 4 Channels

Your Price $29.95

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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 AMP-GM21