About the Metra 70-1856 Bypass Harness

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.
What's in the box:
Metra 70-1856 Bypass Harness owner's manual
- Receiver wiring harness (includes antenna)
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More details on the Metra 70-1856 Bypass Harness

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Features
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:
Wire Color | Function |
---|---|
Black (thick gauge) | Antenna cable |
Red | +12 Volt Accessory |
Yellow | +12 Volt Constant |
Black | Ground |
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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Installed in a 1995 Cadillac Seville SLS. Known to be an absolute "pain in the foot" to repair (even GM mechanics complained which brought a complete re-design by GM two years later), installing this wire harness was not only painless, but effortless. Extremely well made.
sjCohen from Wisconsin