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Metra 70-8121 Amp Bypass Harness

Allows you to install a new car stereo and bypass the factory amplifier in 2005-06 Toyota Tundra Extended Cab trucks with tweeters

Item # 120708121

This Metra 70-8121 amp bypass harness allows you to install a new car stereo in your car without having to cut the...

Read more from Crutchfield writer, Bob B.

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In Stock
$24.99

About the Metra 70-8121 Amp Bypass Harness

Metra 70-8121

This Metra 70-8121 amp bypass harness allows you to install a new car stereo in your car without having to cut the factory wiring, and to directly connect your new car stereo to the speakers in your truck.

Metra 70-8121

This Metra 70-8121 amp bypass harness allows you to install a new car stereo in your car without having to cut the factory wiring, and to directly connect your new car stereo to the speakers in your truck.

Simply splice the color-coded wires on your Crutchfield bypass harness to the wires from your aftermarket stereo — you can crimp or solder the connections in the comfort of your home without having to struggle with splicing wires behind your dash. Next, plug the Crutchfield bypass harness into the harness that you removed from your factory radio.

Since you didn't have to cut off your car's original radio connector, it's easier to put the factory radio back in when you sell your vehicle or return it at the end of the lease. Just plug the factory radio back in and keep the aftermarket stereo. Warranty: 1 year.

Important Note: This harness bypasses your factory amplifier. In order to install it and make the necessary connections, you will need to run wires from the harness to your factory amp location under the right rear seat. 

Please enter your vehicle information or call a Sales Advisor at 1-888-955-6000 to find out if this model is compatible with your vehicle.

READ LESS

What's in the box:

  • 8" Power/ground harness
  • 17' Amp bypass harness
  • Installation Instructions

Customer reviews

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Metra 70-8121 Amp Bypass Harness Reviews

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More details on the Metra 70-8121 Amp Bypass Harness

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Features

Amp Bypass Harness: The Metra 70-8121 Power/Amp Bypass Harness consists of a 8" power/ground harness and 17' amp bypass harness. The 70-8121 is needed to bypass the factory amplifier in select 2005-2006 Toyota Tundra trucks, when replacing the factory radio with an aftermarket head unit.

Note: Installation tools, hardware, & accessories are not included & sold separately. Please see the Accessories tab for recommendations & availability. If your vehicle is equipped with factory steering wheel controls, an additional adapter is required & sold separately.

Wire Code Chart:

Power/Ground Harness
Wire Color Function
Red +12 Volt Accessory
Yellow +12 Volt Constant
Black Chassis Ground
Orange Illumination
Blue Power Antenna

 

Amp Bypass Harness
Wire Color Function
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 (-)
Purple Right Rear Speaker (+)
Purple/Black Right Rear Speaker (-)

 

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Customer Q&A

Q
Crutchfield asked: Why did you buy this?
A
Helping son with new radio [ James  Jan 01, 2019 ]
A
Needed for bypassing O E factory amp. [ Michael  Sep 21, 2018 ]
A
I bought a Pioneer AVH-4100NEX for my 2005 Tundra a couple of years ago and Crutchfield bundled it with an Axxess TYTO-01 Wiring Interface, which didn't allow the rear speakers to work. I really think they should have sent this to me for free. [ Robert  May 30, 2018 ]
A
It was the only option that fit my scenario. [ john  Mar 31, 2018 ]

1 question already asked

Q
I bought this but my amp has two plugs. What do I do with the other one?
[ Jerry  Apr 05, 2018 ]
4 answers
A
It does nothing it's not plugged into anything.
[ Ryan  Apr 25, 2018 ]
A
The Metra 70-8121 adapter is made to adapt an aftermarket head unit to the existing speakers without cutting the stock wiring harness. In order to do this, the existing Toyota amp is bypassed and the two amp plugs are not used. This adapter does not work if you want to use the Toyota amp. I installed a new more powerful Zapco amp thinking this adapter would work from my existing head unit and to my surprise it is not made for this application. I had to tap into the Toyota amp speaker outputs and wire it to an Audio Control line output converter, then wire the converter to the new amp and the new amp to the speakers. Sounds great!
[ DANIEL  Apr 24, 2018 ]
A
On my 2006 Tundra, I just left the other plug plugged in to where it was, I think. Works fine.
[ Theodore  Apr 23, 2018 ]
A
It doesn't go to the amp, it bypasses it. You unplug the amp, remove it, and just plug into the speaker harness that was plugged into the factory amp.
[ DaveH  Apr 23, 2018 ]

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