JBL Bypass with Alpine 5 Channel Amplifier Install Guide | 2014-2021 Tundra

JBL Bypass with Alpine 5 Channel Amplifier Install Guide | 2014-2021 Tundra
Here is a simple and easy breakdown of how to install you new
JBL Amplifier Bypass Plug & Play Bundle with
Alpine 5 Channel Amplifier from Trail Grid Pro!

Installation Video

Coming Soon!

Parts Included:
  • (1) Alpine S2-A55V 5 Channel Amplifier
  • (1) Plug and Play JBL Bypass Harness
  • (1) 3 Meter 6 Channel RCA cables with blue remote wire (Pre-bundled)
  • (1) RCA Splitter with double female adapters
  • (1) Red Power wire
  • (1) In-Line Fuse Block
  • (1) Black Ground Wire
  • (4) Pieces of Velcro
  • (1 each) Male & Female Bullet Connector
  • (1) 10mm Bolt
Tools Needed:
  • 10mm socket
  • 12mm wrench of socket (Secure power wire to positive (+) battery terminal)
  • 14mm wrench or socket (Remove passenger seat bolts)
  • 3 mm allen wrench (Securing wires to amplifier)
  • Panel tool
  • Phillips & Flat head screwdriver
  • Utility knife
  • Wire fish or coat hanger
  • Electrical tape
  • Side cutters
  • Zip Ties
Step 1

Gaining access to the factory JBL amplifier:
  • 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.
Step 2

Remove the factory JBL amplifier:
  • 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 Trail Grid Pro JBL Bypass Harness:
  • 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

Connecting RCA's/Remote wire to aftermarket radio:
  • Connect the provided set of RCA's to the RCA connections for Front, Rear & Sub on the back of your aftermarket head unit.
  • The RCA's are labeled:
    • Front Left (FL) Clear, Front Right (FR) Red
    • Rear Left (RL) Clear , Rear Right (RR) Red
    • Sub Left (SL) Clear & Sub Right (SR) Red
  • If your aftermarket radio only 1 sub out RCA, use the included Y splitter.
    • Connect the Y splitter to the sub out RCA and the other 2 ends to your RCA bundle running to the amplifier. 
  • Connect the remote wire to the amp turn on wire from your aftermarket head unit using the provided bullet connectors.
Step 6

Route the RCA/Remote wire to passenger seat:
  • Route the RCA's down the inside of the passenger side of the dash towards the passenger floor board.
    • Continue around and behind the top of the floor carpet towards the bottom of the A-pillar. 
    • Continue running the RCA bundle through the factory wiring channel until you reach the area under the passenger seat. The wire channel clips can be opened with a small flat head screw driver to release the tab and the top will lift open. 
    • Run the RCA's under the carpet and through the opening in the carpet near the floor vents.
Step 7

Running the power wire from battery:
  • Mock up where you want to mount the fuse block.
    • Connect the short length of power wire with the black shielding to the fuse block ensuring that the grommet is seated in the groove.
    • Attach the other end of power wire with shielding to the fuse block, again ensuring that the grommet is seated in the groove.
    • Secure using the allen wrench.
    • Place the plastic Kicker branded cover over the completed fuse assembly. 
  • Our recommendation is to run the power wire along the inside of the drivers side fender towards the firewall and across the fire wall towards the passenger side firewall grommet. 
  • Use zip ties to secure the wires so that they are free of moving or hot engine components.
  • Locate the main firewall grommet on the passenger side of the vehicle. 
    • Locate a spot to cut an "X" in the grommet using a utility knife. Keep in mind that many Toyota firewall grommets have an exterior and interior membrane that you will need to cut through. Take extra care to not damage any other vehicle wiring when cutting your "X."
  • You may choose to use a wire fish or metal coat hanger to assist in passing the power wire from the engine bay to the interior. 
  • Route the power wire down the kick panel and through the factory wire channel, under the carpet and to the power side of the amplifier.  
  • Connect the power wire to the amplifier and secure with allen wrench.
Step 8

Connecting the ground wire:
  • Connect the provided black ground wire to the amplifier and secure using allen wrench. 
  • Route the provided ground wire under the carpet and ground to factory ground location under the seat using the provided 10 mm bolt.
Step 9

Making connections to the amplifier:
  • Place the  Alpine amplifier under the passenger seat. You may use the provides velcro or the universal brackets to mount it to the carpet or floor. 
    • Do not  permanently mount until all wires have been connected. 

  • Connect the RCA's to the RCA's on the side of the Alpine Amplifier.
    • Connect the Front Speakers:
      • CH-1 L - FL Clear
      • CH-2 R - FL Red
      • CH-3 L - RL Clear
      • CH-4 R - RR Red
      • Sub L - SL Clear
      • Sub R - SR Red
      • Remote wire to REM
  • Connect the speaker wires from the JBL Bypass Harness:
    • Start with the 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
    • Front speaker leads on the top row:
      • CH-1 + White
      • CH-2 + Grey
      • CH-3 + Green
      • CH-4 + Purple

  • Subwoofer Speaker leads (if amplifying factory enclosure)
    • From Trail Grid Pro JBL bypass harness:
      • SUB – (Bottom Row) -Black
      • SUB + (Top Row) - Red
Step 10

Finalize power wire installation:
  • Connect the short length of power wire to the positive battery terminal using the pre-connected ring terminal.
Step 11

Test function:
  • Power on your vehicle and test the audio settings to ensure that your radio and amplifier are working.
  • If your have head unit powers on but you have no sound, check to make sure that you connected the remote turn on wire. 
Step 12

Setting the gains on your new Alpine amplifier:
  • Set Turn-on Type to "REM/LO"
  • Set Input Channel to "3/4"
  • Set Sub Input to "SUB"
  • Find a song that will play for at least a few minutes. 
  • Turn up the volume on your head unit to about 75% of the MAX volume. 
  • Using a small flathead screwdriver adjust the CH-1/2 gain (Front Speakers) until your desired sound level is reached.
  • Repeat the same for the CH-3/4 gain (Rear Speakers) setting.
  • Repeat once more for the Sub gain. 

This will set the overall sound level for your vehicle. If you start to notice distortion or that the sound is clipping or stopping you have set your gains to high!

You can further adjust to your liking using the EQ settings within your head unit. 

Step 13

Once you have confirmed that your system is working and you have set the gains to your liking, reassemble your vehicle and enjoy your new amplified system!

Congratulations on installing your new JBL Amplifier Bypass Harness and Alpine 5 Channel Amplifier!

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