1. Introduction
This manual provides comprehensive instructions for the installation, operation, and maintenance of the RAPTOR by METRA Electronics Bulk Series 4 Gauge AMP KIT, model R2AK4. This kit is designed to provide the necessary wiring and components for connecting an aftermarket amplifier to your vehicle's audio system. Please read this manual thoroughly before beginning installation to ensure proper setup and safe operation.

Figure 1.1: The RAPTOR R2AK4 AMP KIT in its retail packaging, showcasing the main components.
2. Safety Information
Always observe the following safety precautions during installation and use:
- Disconnect the vehicle's negative battery terminal before starting any electrical work to prevent short circuits and electrical shock.
- Wear appropriate safety gear, including eye protection and gloves.
- Ensure all connections are secure and properly insulated to prevent shorts and potential fire hazards.
- Route cables away from moving parts, sharp edges, and heat sources.
- Use the correct gauge wire for your amplifier's power requirements. This kit provides 4-gauge wire, suitable for systems up to 1100W.
- Install the fuse holder as close to the battery as possible (within 18 inches) to protect the power wire from short circuits.
- If you are unsure about any part of the installation process, consult a qualified professional car audio installer.
3. Package Contents
Verify that all components listed below are present in your RAPTOR R2AK4 AMP KIT:
- 17 ft. CCA Power Wire (4 Gauge)
- 3 ft. CCA Ground Wire (4 Gauge)
- 17 ft. RCA Cable
- 20 ft. Speaker Wire
- (1) ANL Fuse Holder with 100 Amp Fuse
- Assorted Hardware (e.g., ring terminals, spade terminals, cable ties, grommet)

Figure 3.1: All components of the RAPTOR R2AK4 AMP KIT, including power wire, ground wire, RCA cable, speaker wire, fuse holder, and various hardware pieces, laid out for inspection.

Figure 3.2: Close-up view of the assorted hardware provided with the kit, such as ring terminals, spade terminals, and cable ties, essential for secure connections.
4. Setup and Installation
This section outlines the general steps for installing your amplifier wiring kit. Specific vehicle layouts may vary. Professional installation is recommended if you are unfamiliar with car audio wiring.
4.1. Planning and Preparation
- Disconnect Battery: Always disconnect the negative terminal of your vehicle's battery before starting any work.
- Determine Amplifier Location: Choose a secure, well-ventilated location for your amplifier, typically in the trunk or under a seat.
- Plan Wire Routing: Plan the path for all wires (power, ground, RCA, speaker) to avoid interference and ensure sufficient length. Route power cables separately from signal cables (RCA) to minimize noise.
4.2. Power Wire Installation
- Route Power Wire: Run the 17 ft. 4-gauge power wire from the battery location through the firewall into the vehicle's interior. Use the provided grommet to protect the wire where it passes through metal.
- Install Fuse Holder: Cut the power wire approximately 12-18 inches from the battery terminal. Install the ANL fuse holder in this section. Ensure the 100 Amp fuse is inserted correctly.
- Connect to Battery: Attach a ring terminal to the end of the power wire connected to the fuse holder and secure it to the positive (+) terminal of the battery.
- Connect to Amplifier: Route the power wire from the fuse holder to the amplifier's power input terminal. Secure with an appropriate terminal (not included in this kit, typically supplied with the amplifier or purchased separately).
4.3. Ground Wire Installation
- Prepare Ground Point: Find a clean, unpainted metal surface on the vehicle's chassis near the amplifier. Scrape away any paint or rust to ensure a good electrical connection.
- Connect Ground Wire: Attach a ring terminal to one end of the 3 ft. 4-gauge ground wire and secure it to the prepared chassis ground point using a self-tapping screw or existing bolt.
- Connect to Amplifier: Route the other end of the ground wire to the amplifier's ground input terminal. Secure with an appropriate terminal. Keep the ground wire as short as possible, ideally less than 3 feet.
4.4. RCA Cable Installation
- Route RCA Cable: Run the 17 ft. RCA cable from your head unit (stereo) to the amplifier. Avoid routing it alongside the power wire to prevent noise interference. Use the opposite side of the vehicle if possible.
- Connect to Head Unit: Plug the RCA connectors into the pre-amp outputs of your head unit.
- Connect to Amplifier: Plug the other end of the RCA connectors into the corresponding inputs on your amplifier.
4.5. Speaker Wire Installation
- Route Speaker Wire: Run the 20 ft. speaker wire from the amplifier's speaker outputs to your speakers. Ensure correct polarity (+ to + and - to -).
- Connect to Amplifier: Connect the speaker wires to the amplifier's speaker output terminals.
- Connect to Speakers: Connect the other ends of the speaker wires to your speakers.
4.6. Final Steps
- Secure Wires: Use the provided cable ties to secure all wires, preventing them from moving or getting damaged.
- Reconnect Battery: Once all connections are made and secured, reconnect the negative battery terminal.
- Test System: Turn on your vehicle and audio system to test the amplifier and speakers. Adjust amplifier settings as needed.
5. Operating Instructions
The RAPTOR R2AK4 AMP KIT provides the essential wiring infrastructure for your car audio amplifier. Once installed, the kit itself does not require "operation" in the traditional sense. Its function is to reliably transmit power and audio signals to and from your amplifier. The operation of your car audio system, including volume control, source selection, and amplifier settings, will be managed through your head unit and the amplifier's controls.
Ensure that all connections remain secure and free from damage to maintain optimal performance of your audio system.
6. Maintenance
Minimal maintenance is required for the RAPTOR R2AK4 AMP KIT. Regular checks can help ensure longevity and performance:
- Inspect Connections: Periodically check all wiring connections (battery, fuse holder, ground, amplifier terminals) to ensure they are tight and free from corrosion.
- Check Fuse: If your amplifier stops receiving power, inspect the 100 Amp fuse in the ANL fuse holder. Replace it with a fuse of the exact same rating if it is blown. Never use a fuse with a higher rating.
- Cable Integrity: Visually inspect cables for any signs of wear, fraying, or damage, especially where they pass through grommets or near sharp edges. Repair or replace damaged cables immediately.
- Cleanliness: Keep the area around the amplifier and wiring free from dust and debris.
7. Troubleshooting
If you encounter issues with your car audio system after installing the AMP KIT, consider the following troubleshooting steps:
| Problem | Possible Cause | Solution |
|---|---|---|
| Amplifier not turning on | Blown fuse in fuse holder. Loose power or ground connection. Remote turn-on wire not connected or faulty. | Check and replace 100 Amp fuse. Verify all power and ground connections are secure. Ensure remote wire from head unit is connected to amplifier. |
| No sound from speakers | Loose RCA connections. Incorrect speaker wiring polarity. Amplifier gain set too low. | Check RCA cables at both head unit and amplifier. Verify speaker wire connections and polarity. Adjust amplifier gain settings (refer to amplifier manual). |
| Engine noise/whining sound | Power and RCA cables routed too close together. Poor ground connection. | Reroute power and RCA cables on opposite sides of the vehicle. Ensure ground connection is clean and secure. |
| Intermittent power/sound | Loose connections. Damaged wiring. | Inspect all connections for tightness. Check all wires for damage and replace if necessary. |
If troubleshooting steps do not resolve the issue, contact a qualified car audio technician or RAPTOR customer support.
8. Specifications
- Model Number: R2AK4
- Power Wire: 17 ft., 4 Gauge, CCA (Copper Clad Aluminum)
- Ground Wire: 3 ft., 4 Gauge, CCA (Copper Clad Aluminum)
- RCA Cable: 17 ft.
- Speaker Wire: 20 ft.
- Fuse Holder: ANL Type
- Fuse Rating: 100 Amp
- Compatible Systems: Up to 1100W
- Product Dimensions: 11.61 x 8.27 x 2.76 inches
- Product Weight: 2.5 Pounds
- Manufacturer: Metra Electronics
9. Warranty and Support
For specific warranty information regarding your RAPTOR by METRA Electronics Bulk Series 4 Gauge AMP KIT, please refer to the documentation included with your purchase or visit the official Metra Electronics website. Keep your proof of purchase for warranty claims.
For technical support or further assistance, please contact Metra Electronics customer service. Contact details can typically be found on their official website or product packaging.





