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Metra

Metra 70-5521 Radio Wiring Harness for Ford 03-Up Amp

  • Based on 3,789 reviews
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Availability: In Stock.
Fulfilled by Amazon
Arrives Monday, Apr 27
Order within 6 hours and 57 minutes
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Style: Wiring Harness


Product Packaging: Standard Packaging


Features

  • Factory amplifier integration harness
  • 2 RCA Plugs plug into aftermarket radio's pre-amp outputs.Includes Ford Lincoln and Mercury 2003-2005 Turbowire and a 8-pin harness with a pair of RCAs for the OE woofer(s)
  • One 24-pin power plug and one 8-pin subwoofer plug
  • 1.5K Ohm resistor can be used on the amp-remote wire to eliminate turn-on pop
  • Allows for the installation of an aftermarket radio using the existing factory wiring and connectors

Description

We at Metra always strive to listen to our customers. You have told us to do a better job at telling the Metra sto ry. For over 70 years, Metra has maintained its cutting edge by paying attention to our marketplace and innovating products to fit the needs of the installer. We are the "Installer's Choice" because we are installers. We design our products to be easy to use and easy on the eyes. If you can see a Metra product, then we haven't done our job. Metra Turbokits are designed to be heard but not seen. This means that our fit and finish is the best in the business. Why trust your installation to a shoddy and time consuming kit? Our GSXL Turbowires are designed with the same philosophy in mind. Their longer length for ease of installation and thicker OEM cables with OEM connectors make for a mighty install, with no down time on returns or angry customers.

Brand: Metra


Material: Copper, TPU


Item dimensions L x W x H: 0.02 x 0.02 x 0.02 inches


Item Weight: 0.02 Pounds


Connector Type: RCA


Brand Name: Metra


Manufacturer: METRA Ltd.


UPC: 086429129522


Warranty Description: Please contact the manufacturer


Global Trade Identification Number: 22


Part Number: 70-5521


Model: 70-5521


Unit Count: 1.0 Count


Included Components: Wiring Harness


Item Type Name: Sub-Plug For Select 2003-2005 Ford Vehicles With Premier Radio


Item Dimensions: 0.02 x 0.02 x 0.02 inches


Item Weight: 0.02 Pounds


Connector Type: RCA


Material Type: Copper, TPU


Cable Type: RCA


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Monday, Apr 27

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Similar Products

Top Amazon Reviews

    • Steering wheel function, no need to buy extra harness
Style: Wiring Harness Product Packaging: Standard Packaging
I used this harness to upgrade to an aftermarket head unit on my 2005 f250 6.0. Worked flawlessly. My new headunit did not come with steering wheel control functions and says you have to buy the harness for it seperately. You do not. Its a very simple process to retain your functions that i learned about way later. Your upgraded headunit will have a harness included. On that harness it will have a wire labeled "Steering wheel key (+)" and it is orange with a black stripe (atleast on mine) Your stock truck harness will have a blue/red stripe wire on Pin #18 that you must tap into. You dont have to cut it, you can simply military splice it, or use a T-tap to connect the SWK wire on your aftermarket radio harness to connect to your factory harness. Once you connect this SWC(+) wire onto the blue/red wire.. you will be able to setup your functions on your radio. Thats it. One wire. No need to buy the access module or the maestro kit thats around 100 if you have a powerstroke. Hope this helps someone. ... show more
Reviewed in the United States on April 11, 2025 by Veronica
    • Great product, as described. Made installation a breeze
Style: Wiring Harness Product Packaging: Standard Packaging
If you’re using this, look into other accessories to retain steering wheel control too. Draw a wiring diagram. Make sure you have everything you need. It works perfectly. Used it to install KENWOOD DDX9707s on a 2010 Lincoln Towncar. Glad I bought it. Make sure you buy butt connectors to connect the harness with your radio/steering wheel control ... show more
Reviewed in the United States on March 4, 2025 by Robert
    • Great fit for 2008 Hyundai Sonata
Style: Wiring Harness Product Packaging: Standard Packaging
Review Image by Maricela Maricela
Even thought this is labeled for Ford, this was a perfect fit for my 2008 Hyundai Sonata. This item comes with two adapters, I did not need to use the harness with the smaller adapter, I believe this might be to connect an amp which I did not need. I was struggling to find the correct adapter for the 2008 Hyundai Sonata because searching on amazon and google were not leading me to this adapter from Metra since it is labeled for Ford. I came across a youtube video with a guy working on the Hyundai Sonata 2008 and he was using this specific cable model Metra 70-5521 on his stereo. So I decided to order it after searching it up and comparing the adapter to the car's factory adapter. It worked out great because it was a perfect fit. I youtubed enough about the basics of wiring cables together, what the different colors mean, pros and cons of wiring directly to the factory unit wiring (using no adapter). I found videos of others removing the stereo for my specific car (I didnt want to just pry it apart and damage something). Then I went the method of butt connectors to link the wires from this harness to the cables of the stereo unit. The connection quality is strong, the cables from this harness are sturdy so they link well. I used it to adapt an aftermarket radio (BOSS Audio Systems 616UAB single din) using the car's existing factory wiring and connectors. I got the single din install kit (Metra 99-7320). I also got the LeeKooLuu Backup Camera and wired it to the Reverse tail light. I installed this for my girlfriend and it passed her approval test. Everything came together perfectly. ... show more
Reviewed in the United States on June 27, 2025 by Maricela Maricela
    • Works well, BUT
Style: Wiring Harness Product Packaging: Standard Packaging
I used this in an '06 Mustang GT. It was easy to wire up, everything was labeled nicely and wiring is good quality. If you have an amp, there are a couple extra items you may need. First is a 12v to 5v voltage converter, this just gets tied into the amp out (blue/white), otherwise you may get popping sounds with On/Off. The second in my case, I needed to add a line out converter from the RCA. This allows me to adjust the gain. Initially I wired this up without it and the sound was terrible, way too much volume sound coming from the amped speakers. I emailed their tech support a few times, they were helpful but ultimately the manufacturer of the head unit I bought recommended the solution. Otherwise it works as intended. ... show more
Reviewed in the United States on July 25, 2019 by adam malecha
    • Does the job, I was just unclear as to wether I needed the amp out plug
Style: Wiring Harness Product Packaging: Standard Packaging
Just bought a ‘04 Lincoln Town Car and didn’t know wether it had an amp/sub or not(couldn’t speak with original owner as it was purchased through a family member and the manual was missing) so I went with this harness because if I didn’t need the amp out harness no big deal, but if I did...well then I’d need it lol. The harness itself is perfect for what it is, a simple harness to prevent cutting and splicing the OEM harness, wires were clearly marked and colors matched the harness for the after market stereo. Went with the Pioneer AVH-X490BS, if you get a pioneer look into getting the parking brake bypass switch. The only problem is that there was nowhere to connect the two blue wires on the harness with the RCA plugs, so I assumed I didn’t need it and just didn’t use it. Reconnected negative terminal on battery and tested radio and it worked great so I figured I was right. I go to install the Infinity Kappa speakers in the rear deck(btw if you have a Town Car be ready to take out the entire rear seat, both bottom and rear cushions to get access to the speakers......) and guess what I see?? A sub and amp.... I was planning on getting an amp for the speakers anyways, and maybe a 8” sub just for a little bass so I’ll just wait to get them rather than hook up the factory amp/sub. If you're replacing a radio you can’t go wrong with Metra, always quality products. Been using them as long as I can remember, and between work, my personal vehicles and friends/family I’ve installed more car stereos and speakers than I can remember and never had an issue with Metra. ... show more
Reviewed in the United States on May 27, 2018 by Jeff
    • Made it easy
Style: Wiring Harness Product Packaging: Standard Packaging
perfect, color to color
Reviewed in the United States on March 15, 2025 by Larry A. Johnson

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