Metra 70-2550 Receiver Wiring Harness
Connect a new car stereo in select 1979-83 Mercedes vehicles
Item #: 120702550
Your price: $16.99 Earn up to 17 Rewards points
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Item #: 120702550
Your price: $16.99 Earn up to 17 Rewards points
This vehicle-specific wiring harness makes connections between your new car stereo and your car's electrical system.
First, attach the color-coded wires on your Crutchfield-supplied harness to the wires from your new stereo. If you're not using a soldering iron, we recommend that you purchase some wire connectors to secure the connections. Check out our handy article on three ways to connect the wiring harness here.
Now, once this harness is connected to your new stereo, you'll be able to plug right into your car's factory radio connector. This harness makes installing your new stereo easier, and allows you to put the factory radio back when you sell your vehicle or return it at the end of the lease. A detailed instruction sheet comes with the harness. Warranty: 60 days.
Please read this important note: This harness may not contain provisions for every wire needed to complete your installation, and it will not accommodate special navigation, video, or factory steering wheel control connections. You will need a special adapter if you want your factory steering wheel audio controls to work with your new stereo.
Notes: The 12V constant power lead may not be present in your car. If not, and your receiver requires a constant 12V memory lead (most do), run a wire directly to the battery or an appropriate un-switched fuse. To connect the power and ground connection plug, you'll disconnect the cigarette lighter, plug one end of the Crutchfield harness into the lighter, and the other end into the vehicle's harness. If your vehicle has a power antenna, you'll need to connect the new receiver's antenna turn-on lead to the female spade connector in your vehicle. This connector will be on the end of a blue wire which may be covered with black tubing.
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.
This kit has an adapter that plugs into the cigarette lighter connection to use as power/ground. THE MERCEDES +/ - WIRES FOR THE LIGHTER ARE REVERSED FROM THE FACTORY, BLACK IS POSITIVE. I checked this with a multimeter. Solder the RED head unit wire to the BLACK adapter wire. Still maintains the cigarette lighter function. Worked Well. Also has 4 speaker connections that match the factory harness. Work well also.
FYI. Mercedes 123 chassis. The old factory head unit is "2-channel" that runs to the front/rear fader in the shift console, THEN out to the 4 speakers. The R and L speakers have a common ground, in the harness, going to that fader. Snip the wires at the fader, feed/pull them back up to the head unit location. Cut the cover off and snip the R/L common grounds loose. Use a flashlight battery to "static" find the respective +/- speakers/wires. (I THINK green and green/ black were left positives and red and red/black were right positives). Solder up your new "4-channel" head unit.
My team of lawyers says to tell ya'll to "use this info at your own risk".
Pros: The connections were correct.
Cons: The speaker wires were already in my car. Maybe from a previous kit...
Product didn't work with existing wiring. Had to pay for professional install. Spoke with tech support who stated harness takes rewiring. 1983 Mercedes FYI. Bummer as I thought it was a self install.
The hot and ground wires were reversed!!!! I spent 2 days pouring over what I had done wrong in the install before I decided to check if crutchfield had made a mistake, and low and behold the red wire plugs straight into the brown wire on the car (chassis ground). However, the original factory power dongle was easy to modify so I just used that.
I did not remove the manual fader, but I don't understand how the small rear speaker wires would connect to where I believe the rear speaker plugs are under the center console, seemed to short, but maybe I'm wrong.
Pros: Speaker wire plugs fit well.
Cons: Power was wired backwards!!!! Power dongle fits WAY too tight to factory harness, worried I was damaging factory plug upon subsequent removals No good details on how to bypass the manual fader and wire the rear speakers up directly (not something I was planning on doing anyways, I think the manual fader is awesome and I don't have high powered speakers anyway).
Very easy to install.
Purchased for a 1977 MB 300D. My car had pin connectors not the spades in the harness that was provided. Tossed the harness and hardwired the receiver plug.
The harness made it a breeze to install ..only problem I had was the power and ground harness was mixed up ..so negative was positive and positive was negative ...
Crutchfield Wiring Harness: Crutchfield wiring harnesses prevent 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 Crutchfield 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 Crutchfield 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 Crutchfield 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 & sold separately.
Wire Code Chart:
|Red||+12 Volt Accessory|
(4 Individual Speaker Harnesses - Left Front, Right Front, Left Rear, Right Rear )
|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 -|
No Constant Power Wire: This harness does not contain a 12V constant power wire and The 12V constant power lead may not be present in your car. If not, and your receiver requires a constant 12V memory lead (most do), run a wire directly to the battery or an appropriate un-switched fuse. To connect the power and ground connection plug, you'll disconnect the cigarette lighter, plug one end of the Crutchfield harness into the lighter, and the other end into the vehicle's harness.
Power Antenna: If your vehicle has a power antenna, you'll need to connect the new receiver's antenna turn-on lead to the female spade connector in your vehicle. This connector will be on the end of a blue wire which may be covered with black tubing.
The Crutchfield Car Selector: Please visit the Crutchfield Car Selector for your specific type of vehicle.
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