Welcome to the installation guide for your 2014-2021 Tundra Alpine Plug & Play 5-Channel Amp & Subwoofer Kit from Trail Grid Pro! This step-by-step guide is designed to make the installation process as smooth as possible, whether you're a seasoned DIYer or tackling your first head unit upgrade.
In this guide, you’ll find:
- 📢 Important Updates: The written guide includes the latest updates and adjustments that may not be shown in the video, ensuring you have the most up-to-date instructions for a flawless installation.
- 🎥 Installation Videos: Visual instructions to help you through the process, including a detailed microphone install.
- 🛠️ Parts Included and Tools Needed: A quick list of everything you'll need to get started.
- 📝Step-by-Step Instructions: Clear, easy-to-follow directions from disassembling your dash to securing the new Sony head unit.
- ⚠️ Special Notes: Important information and considerations for your installation.
- 🛠️ Common Troubleshooting Solutions: Quick and effective fixes for common installation and performance issues.
Table of Contents
- Important Updates
- Installation Video
- Tools Needed
- Step 1: Disassembling the dash
- Step 2: Disassembling your Tundra
- Step 3: Connecting the amplifier bypass (Amplified Non-JBL Only)
- Step 4: Removing the door sill and kick panel
- Step 5: Routing the power wire
- Step 6: Routing the main harness
- Step 7: Making connections to the head unit
- Step 8: Reinstall your head unit
- Step 9: Connecting the ground wire
- Step 10: Connecting the bass control knob
- Step 11: Mount the amplifier to amplifier bracket
- Step 12: Make connections to amplifier
- Step 13: Route the subwoofer wire
- Step 14: Connect power to battery
- Step 15: Test system
- Step 16: Tune the amplifier
- Step 17: Reassembly
🎥Installation Video
🛠️Parts Included:
- Alpine S2-A55V 5-Channel Amplifier
- AudX Tundra Amplifier Mounting Bracket
- AudX T-Harness
- AudX Main harness
- Amplifier Bypass Harness (Amplified Non-JBL Vehicles Only)
- RCA adapters
- Trail Grid Pro Amplifier Install Kit
- 10 Zip Ties
- 10mm Ground Bolt
🛠️Tools Needed:
- Panel removal tool
- 10 mm socket
- 12 mm socket
- 14 mm socket
- Ratchet wrench
- Socket extension
- Phillips head screwdriver
- Zip ties
- Razor knife
- Wire fish
Step 1: Disassembling the Dash
- Remove the lower dash panel that contains the USB ports.
- Insert a panel removal tool into the gap between this panel and the HVAC panel. Once loosened, pull straight back to release the retaining clips.
- Pull the HVAC panel straight out using your hands.
- Disconnect the single plug from the back of the HVAC control panel.
- To remove the factory head unit:
- Use a 10 mm socket and extension to remove the four 10 mm bolts securing the bottom of the radio. Store them in the cup holder for safekeeping.
- Pull the head unit straight back to release the upper retaining clips.
- Disconnect all wiring connections from the back of the radio by pressing the tabs on each connector and unplugging them.
Step 2: Disassembling Your Tundra
Remove the center console:
- Twist the gear shifter handle counterclockwise to remove it.
- Open the center console.
- Lift up on the shifter panel to remove it.
- Disconnect any wire connections before fully removing.
- Pull straight out to release the retaining tabs.
- Disconnect any connectors before removing the panel completely.
Removing the front passenger seat:
- Remove two 14 mm bolts holding the passenger front seat bracket in place.
- Slide seat forward to access the rear seat bolts.
- Gently lift up while pulling back on trim to remove the two plastic trim pieces covering the rear 14 mm bolts.
- Remove the two 14 mm bolts.
- Slide seat back, lift up and lean back to give access under seat or unplug up to three plugs and remove seat from vehicle.
Remove the factory Non-JBL amplifier (Amplified Non-JBL Vehicles Only):
- Remove the three black plastic hold down pins using a panel tool.
- Remove black plastic cover over amplifier.
- Remove all three plugs located on the side of the amplifier.
- Lift the carpet flap to expose the amplifier mounting bracket.
- Remove the three 10 mm bolts holding amplifier to vehicle and remove from the vehicle.
Step 3: Connecting the amplifier bypass harness (Amplified Non-JBL Vehicles Only)
- The bypass harness has two plugs:
- One 10 pin connector.
- One 12 pin connector.
- Match the appropriate connectors to the factory plugs and connect.
Step 4: Removing door sill and kick panel trim:
- Passenger front door kick panel trim:
- Remove screw on knob securing panel to floor.
- Pull the panel to the left to remove the retainers.
- Passenger door sill:
- Using a panel tool or your fingers gently pry the floor trim up until free.
- Lift and remove from vehicle.
Step 5: Routing the Power Wire
- Prepare the Power Wire:
- Open the hood and secure it in place.
- Locate the power wire with the inline fuse included in your kit.
- Connect the short power wire to one side of the inline fuse by securing the wire ferrule using a 3 mm Allen key.
- Connect one end of the longer power wire to the other side of the inline fuse the same way.
- Route the Power Wire:
- Place the ring terminal near the positive battery terminal (do not connect it yet).
- Route the power wire along the driver’s side fender, across the firewall, and toward the passenger-side firewall grommet.
- Pass Through the Firewall:
- Use a utility knife to carefully cut an "X" in the firewall grommet to allow the power wire to pass through.
⚠️ Note: Many Toyota firewall grommets have both an exterior and interior membrane—cut through both.
⚠️ Be careful not to damage any vehicle wiring while cutting.
- Use a wire fish tool if necessary to guide the ferrule end of the power wire into the cab.
- Once the wire is through the firewall, pull the slack into the passenger-side floorboard.
- Use a utility knife to carefully cut an "X" in the firewall grommet to allow the power wire to pass through.
- Run the Power Wire to the Amplifier:
- Route the wire down the passenger-side kick panel and through the factory wire channel.
- Run the wire under the carpet to the power side of the amplifier.
- Use the provided zip ties to secure any loose wiring in the engine bay.
Step 4: Routing the Main Harness
- Route the Main Harness:
- Position the main harness under the front passenger seat.
- Start with the T-harness end and begin routing it toward the head unit.
- Run the harness under the carpet, directing it toward the gear shifter.
- Continue routing the harness through the transmission tunnel area, moving toward the front of the vehicle.
- Guide the T-harness up inside the dash, routing it towards the main radio connections.
Step 5: Making Connections to Your Head Unit
For 2014–2019 Models
Factory Head Unit:
- Disconnect the 10-pin and 6-pin and from the back of the head unit.
- Plug the male end of the AudX T-Harness into the 10-pin and 6-pin ports on the head unit.
- Attach the vehicle’s 10-pin and 6-pin connectors to the female end of the AudX T-Harness.
- ⚠️ (Optional) If grounding the harness, secure the black wire with the small ring terminal to a clean metal-to-metal ground location.
Aftermarket Head Unit:
- Disconnect the 10-pin and 6-pin connectors from the back of the head unit.
- Connect the male end of the AudX T-Harness to the 10-pin and 6-pin ports on the head unit.
- Attach the vehicle’s 10-pin and 6-pin connectors to the female end of the AudX T-Harness.
- Connect RCA cables to the RCA outputs on the aftermarket radio.
For 2020–2021 Models
Factory Head Unit:
- Disconnect the 10-pin and AM/FM antenna connector from the back of the head unit.
- Connect the male end of the AudX T-Harness to the 10-pin and AM/FM antenna port on the head unit.
- Attach the vehicle’s 10-pin and AM/FM antenna connector to the female end of the AudX T-Harness.
- If you choose to ground the harness, secure the black wire with small ring terminal to ground location, ensuring it is a good metal to metal contact.
Aftermarket Head Unit:
- Disconnect the 10-pin and AM/FM antenna connector from the back of the head unit.
- Connect the male end of the AudX T-Harness to the 10-pin and AM/FM antenna location on the head unit.
- Attach the vehicle’s 10-pin and AM/FM antenna connector to the female end of the AudX T-Harness.
- Connect RCA cables to the RCA outputs on the aftermarket radio:
- Front Speakers:
White → White
Grey → Red - Rear Speakers:
Green → White
Purple → Red - Subwoofer:
Orange → White
Brown → Red
- Front Speakers:
- ⚠️ (Optional) If grounding the harness, secure the black wire with the small ring terminal to a clean metal-to-metal ground location.
Step 6: Reinstall Your Head Unit
- Reconnect and Reposition:
- Ensure that all previously disconnected wiring connections are securely reattached.
- Carefully position the head unit back into the dash.
- Fasten the head unit using the four factory 10 mm bolts.
⚠️ Important: Do not fully reassemble the dash at this point—functionality should be tested before completing the installation.
Step 7: Connecting the Ground Wire
- Secure the Ground Connection:
- Use the provided ground wire to connect the ring terminal to the factory ground point located under the passenger seat.
- If a factory ground bolt is not present, use the included bolt to secure the ring terminal to the pre-threaded hole under the seat.
Step 8: Connecting the Bass Control Knob
- Mount and Connect the Bass Knob:
- Attach the bass control knob in your preferred location using the included Velcro, or install it into one of our Switch Blank Mounts.
- Route the control knob wire from the main harness and plug the 3.5mm headphone jack into the bass control knob.
- Use zip ties to secure any excess or loose wiring.
Step 9: Mount Amplifier to Amplifier Mounting Bracket
- Install the Amplifier:
- Place the amplifier mounting bracket with the AudX label facing up.
- Align the amplifier with the pre-drilled holes on the mounting bracket, orienting it so the RCA ports face the rear of the vehicle.
- Insert one bolt up through the bottom of the amplifier mounting bracket, then through the amplifier’s mounting hole.
- Place a flat washer, followed by a split washer, and secure it with a nut.
- Use a 9/32" wrench and a Phillips head screwdriver to tighten the hardware.
⚠️ Do not overtighten. - Mount the amplifier bracket to the floor pan using the factory hardware by securing the 10 mm bolts back to the factory locations.
Step 10: Making Connections To Amplifier
- RCA Input Harness:
- Use a Phillips-head screwdriver to remove one screw from the amplifier's control faceplate.
- Place the ring terminal from the ground wire over the screw.
- Re-secure the screw to fasten the ground.
- Connect the RCA's:
- CH-1 L - FL White
- CH-2 R - FL Grey
- CH-3 L - RL Green
- CH-4 R - RR Purple
- Sub L - SL Orange
- Sub R - SR Brown
- Connect the Remote Wire:
- Insert the remote wire ferrule into the REM input on the amplifier.
- Tighten the screw using a 2 mm Allen wrench.
- Connect the harness to the 4-pin connector on the main harness.
- Wire Ferrule Harness
- Connect the harness to the 8-Pin connector on main harness.
- Make the following speaker connections:
- Rear speaker leads on the bottom row:
- CH-1 - White/Black Stripe
- CH-2 - Grey/Black Stripe
- CH-3 - Green/Black Stripe
- CH-4 - Purple/Black Stripe
- Rear speaker leads on the bottom row:
- Front speaker leads on the top row:
-
- CH-1 + White
- CH-2 + Grey
- CH-3 + Green
- CH-4 + Purple
-
- Subwoofer Wire
- Connect wire ferrule ends to amplifier:
- Sub - Black Wire
- Sub + Red Wire
- Connect wire ferrule ends to amplifier:
- Connect Ground and Power Wires:
- Connect the provided black ground wire to the amplifier and secure it using a 2 mm Allen wrench.
- Connect the power wire to the amplifier and secure it with a 2 mm Allen wrench.
Step 11: Route Subwoofer Wire
- Route the wire to behind the rear seat:
- Remove the rear door sill by pulling straight up.
- Route the subwoofer wire through the factory wiring channel toward the rear seat.
- Press the subwoofer wire under the interior plastic panels and continue routing it to the rear seat.
- Connect to the Subwoofer:
- Connect the yellow wire to the positive (+) terminal.
- Connect the black wire to the negative (–) terminal.
Step 12: Connect Power To Battery
- Connect the Power Wire:
- Locate the short length of power wire with the pre-connected ring terminal.
- Connect the ring terminal securely to the positive battery terminal.
Step 13: Test System
- Power On and verify functionality:
- Turn on your vehicle and test the audio system.
- Confirm that both the radio and amplifier are functioning properly.
🛠️Troubleshooting Tip:
If the head unit powers on but you hear no sound, double-check that the remote turn-on wire is properly connected.
Step 14: Tune The Amplifier
- Set Initial Amplifier Settings:
- On your Alpine S2-A55V amplifier, set the following:
- Fader: ON
- Input Level: LO
- Sub Input: SUB
- On your Alpine S2-A55V amplifier, set the following:
- Adjust Gain Levels:
- Choose a song that plays continuously for a few minutes.
- Turn the volume on your head unit to about 75% of the maximum volume.
- Using a small flathead screwdriver, adjust the Amp 1 gain (Front Speakers) to your desired sound level.
- Repeat the process for the Amp 2 gain (Rear Speakers).
- Adjust the Sub gain last to set your desired bass level.
- ⚠️ Warning: If you hear distortion, clipping, or audio cutting out, the gain is set too high—reduce accordingly.
- Final Adjustments:
- Use your head unit’s built-in EQ settings to fine-tune the overall sound to your personal preference.
Step 15: Reassembly
- Reinstall the Seat:
- Once you’ve confirmed the system is functioning properly and your amplifier gains are set, begin reassembly.
- Place the passenger seat back into position, aligning the rear seat mounts.
- Start all four 14 mm seat bolts by hand, then tighten them using a 14 mm socket.
- Once you’ve confirmed the system is functioning properly and your amplifier gains are set, begin reassembly.
- Finish Reassembling the Vehicle:
- Reinstall all remaining components, including the rest of the seat, center console, and dash panels.