Metra Factory Amplifier Harness for 2004-Up Toyota JBL - Amp Bypass

In this review the Metra factory amplifier harness bundle is examined for installers and Toyota owners who need a reliable way to integrate or bypass factory JBL amplifiers. The combined offering includes the 70-8117 harness for 2004-up Toyota vehicles with JBL systems and the 70-8113 amplifier integration harness for select 2000-2004 models. The single biggest reason to consider this kit is compatibility: it plugs into OEM radio connectors and preserves the factory amplifier where required, simplifying installation and avoiding cutting into factory wiring when swapping an aftermarket head unit.

Key Features

• Direct OEM connections: The 70-8117 includes a 24-pin plug that mates to the factory radio, which reduces guesswork during installation and preserves factory connectors.
• Amplifier retention option: The 70-8113 is an integration harness that retains the factory amplifier and routes low level RCA outputs from an aftermarket radio to the vehicle amp for cleaner signal transfer.
• Long power harness: A 204 in power lead on the 70-8117 provides enough reach for routing through larger cabins or double cab trucks without stretching or extensions.
• Factory amp location reference: The product notes common factory amp locations by model, helping installers find the amp quickly in 4Runner, Matrix, Prius, Sequoia, Sienna, Solara, Tacoma and Tundra models.
• Prepped for low level inputs: The 70-8113 is set up for low level RCA inputs, which helps maintain better sound quality when using an aftermarket head unit.

Who It's For

This bundle is aimed at DIY installers and pro shops working on Toyota vehicles equipped with JBL systems from the listed years who want to swap a head unit without losing amp functionality or who need a clean bypass solution. It suits owners of 2003-2006 4Runner, 2004-2006 Sienna, 2005-2006 Tacoma, 2004-2006 Tundra and similar models where factory amp locations are documented.

It's less suitable for vehicles outside the listed model years or Toyota vehicles with non-JBL OEM wiring variations that were reported by some customers to cause fit issues. If your vehicle uses an uncommon connector or you need a fully universal harness, consider a vehicle-specific adapter or a custom wiring approach instead.

Pros & Cons

Pros

• Plugs into OEM radio connectors for a cleaner, less invasive install.
• Retains factory amplifier with low level RCA outputs for improved aftermarket integration.
• Long 204 in power lead gives flexibility in routing for larger vehicles and double cabs.
• Pre-stripped leads and clear wiring reduce installation time for experienced installers.

Cons

• Some users reported compatibility and fit issues with certain JBL connector variants, so verify connector type before purchase.
• Not universally applicable to all Toyota years and trims; check model fit list carefully.

Specifications

Our Verdict

The Metra harness pair is a practical choice for installers who need a near-direct replacement for Toyota JBL systems and who want to retain the factory amplifier or bypass it cleanly. It represents good value when the connector types match the vehicle; its long power lead and low level RCA setup make it flexible for many installations. Buyers should confirm connector compatibility beforehand to avoid the occasional fit issue reported by some owners.

Frequently Asked Questions

Will this harness retain my factory amplifier?
The 70-8113 is specifically designed to retain the factory amplifier and provide low level RCA outputs to the aftermarket radio.

Does the 70-8117 plug directly into the OEM radio?
Yes, the 70-8117 uses a 24-pin plug that connects to the OEM radio on compatible Toyota JBL systems.

Is the power lead long enough for trucks?
Yes, the 70-8117 includes a 204 in power lead, which is sufficient for routing in larger cabins and double cab trucks.