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Metra 70-1856 Bypass Harness
Allows you to connect a new car stereo to factory wiring in select 1990-96 GM vehicles with non-Bose® systems
Item # 120701856 | MFR # 70-1856
$39.99 Earn up to 40 Rewards points
Our take on the Metra 70-1856 Bypass Harness by Crutchfield's Zak Billmeier
This Metra 70-1856 bypass harness lets you replace the factory radio in select 1990-96 GM vehicles without the factory Bose® system, using the existing wiring and connectors. This harness bypasses the remote tuner in certain vehicles. Warranty: 1 year.
Please enter your vehicle information or call an Advisor at 1-888-955-6000 to find out if this model is compatible with your vehicle.
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.
Metra 70-1856 Bypass Harness Reviews
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Wiring Harness: This wiring harness prevents you from having to cut your vehicle's factory radio plug when replacing your factory radio with an aftermarket head unit. Simply solder or crimp the wiring harness to your aftermarket head unit's harness (solder & crimps not included), plug the aftermarket head unit's plug into the rear chassis of the aftermarket head unit, and plug the wiring harness into your vehicle's factory radio plug.
Note: Installation tools, hardware, & accessories are not included & sold separately. Please see the Accessories tab for recommendations & availability.
Wiring Notes: If the wiring harness is not equipped with a ground wire, you will need to ground the aftermarket head unit's ground wire to the metal chassis of your vehicle. Some vehicle's may require you to bypass the vehicle's factory amplifier (in another location from factory radio) or hardwire certain connections. If your vehicle is equipped with factory steering wheel controls, an additional adapter is required and sold separately.
Wire Code Chart:
|Black (thick gauge)||Antenna cable|
|Red||+12 Volt Accessory|
|Yellow||+12 Volt Constant|
|Blue||Power Antenna/Amp Turn-On|
|White||Left Front Speaker +|
|White/Black||Left Front Speaker -|
|Gray||Right Front Speaker +|
|Gray/Black||Right Front Speaker -|
|Green||Left Rear Speaker +|
|Green/Black||Left Rear Speaker -|
|Violet||Right Rear Speaker +|
|Violet/Black||Right Rear Speaker -|
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1 question already asked
The Metra 70-1856 Bypass Harness is the only option we offer for a 1993 Cadillac Fleetwood. Our research file notes "The factory radio has a remote tuner module mounted in the trunk. Any electrical connections will need to made there and then all wiring will need to be extended back to the dash location." For more details or assistance, please feel free to speak to an Advisor by phone (888.955.6000) or online chat ("Contact Us" link at the top of the webpage). I hope that helps! [ Larry Sep 08, 2016 ] Staff