MBQJL-302 - Subwoofer MB QUART - Free user manual and instructions

Product Type	Subwoofer Enclosure with Speaker
Brand	MB Quart
Model	MBQJL-302
Compatible Vehicles	Jeep Wrangler JL (2018+) and JK (2007-2018)
Subwoofer Size	12 inches
Enclosure Type	Loaded (includes subwoofer)
Impedance	4 ohms (typical)
Power Handling (RMS)	400 Watts (estimated)
Peak Power	800 Watts (estimated)
Frequency Response	30 Hz - 200 Hz (estimated)
Sensitivity	88 dB (estimated)
Grill Included	Yes
Wiring Harness Included	Yes
Installation Hardware Included	Screws, bolts, spacers, L brackets, zip ties, rubber plugs, gasket
Assembly Time	90 minutes (1.5 hours)
Mounting Location	Tailgate panel
Warranty	1 year limited

Frequently Asked Questions - MBQJL-302 MB QUART

What vehicles is the MBQJL-302 compatible with?

The MBQJL-302 is designed for Jeep Wrangler JL (2018+) and Jeep Wrangler JK (2007-2018) models.

Does the enclosure come with a subwoofer?

Yes, the MBQJL-302 is a loaded enclosure with a 12-inch subwoofer. There is also an unloaded version (MBQJL-302E) sold separately.

What tools are required for installation?

You will need a panel tool, T20 and T40 Torx drivers, a drill, 4mm Allen wrench, 10mm socket, and a threaded insert tool (for JK models). A 9/16" drill bit (JL) or 23/64" drill bit (JK) is also required.

How do I connect the subwoofer wiring?

Connect the red wire to the positive (+) terminal and the black wire to the negative (-) terminal of the subwoofer. Then secure the wiring with zip ties and connect the extension harness to your amplifier.

Is the enclosure weatherproof?

The enclosure is designed for interior installation in the tailgate. It is not weatherproof and should not be exposed to moisture.

What is the power handling of the subwoofer?

The manual does not specify exact power ratings, but typical MB Quart 12" subwoofers handle around 400W RMS. For optimal performance, match the amplifier RMS power to 400W at 4 ohms.

Can I use this enclosure with an aftermarket amplifier?

Yes, the subwoofer is passive and requires an external amplifier. Use the included wiring harness to connect to the amplifier.

How do I install the grill?

Install the white gasket into the channel of the grill, then attach the grill to the enclosure using six ST4.2x19mm screws with a T20 Torx driver. Do not overtighten.

What is the warranty period?

MB Quart offers a 1-year limited warranty from the date of purchase. It covers defects in materials and workmanship under proper installation and use.

Can I install this in a Wrangler JK without a trail rail?

Yes, but you must drill four 23/64" holes and install threaded inserts. An alignment template is available; contact [e-mail] for assistance.

USER MANUAL MBQJL-302 MB QUART

Installation Instructions

Model:	Jeep Wrangler JL (Pg.1-5 & 12) & Jeep Wrangler JK (Pg.6-12)
Description:	MB Quart Jeep JL Wrangler 12" Subwoofer Enclosure
Part Number:	MBQJL-302MBQJL-302E - Unloaded Enclosure
Assembly Time:	90 Minutes (1.5-Hours)

Before you begin, read through these instructions and check that all parts are present. Please note that MB Quart cannot assume any responsibility for damage resulting from incorrect installation.

Parts List
No.	Component Name Qty
1	Subwoofer Enclosure 1
2	ST4.2 x 19mm Screw 14
3	M6 x 60mm Flathead Screw 2
4	M6 x 60mm Bolt 2
5	7mm Rubber Plug 4
6	9mm Rubber Plug 2
7	L Bracket 2
8	M6 x 16mm Torx Screw 2
9	M6 x 40mm Hex Bolt with Flange (Wrangler JK/JKU Only) 4
10	13 x 30mm Spacer 2
11	13 x 45mm Spacer 2
12	M6 Washer	2
13	8" Zip Tie 6
14	Grill	1
15	White Gasket	1
16	Wire Harness	1

Tools Required
1 Bojo or Panel Tool
2 T20 Torx Driver
3	T40 Torx Driver (Trailrail Equiped Only)
4 9/16" Drill Bit | 23/64" Drill bit (Wrangler JK/JKU Only)
5 Drill
6 4mm Allen Wrench
7 10mm Socket
8 Threaded Insert Rivet Nut Tool

Disassembly Instructions

- Remove four T20 Torx screws holding the subwoofer in the enclosure. Then disconnect the wiring from the subwoofer.

Close-up of a speaker with exposed microphone and wires, no visible text or symbols

• Install four 7mm rubber plugs into the inside of the enclosure.

Close-up of a speaker bowl with MBI QUART branding being inserted, no visible text or symbols on the device itself.

Black plastic mechanical component with four red-circled holes, placed on a workbench (no text or symbols visible)

Four black rubber caps arranged on a white surface with visible cracks (no text or symbols)

• Install the white gasket material into the channel of the grill.

Close-up of a black plastic tray with white wire and a small hole, resting on a textured surface (no text or symbols visible)

Coiled white cable on a concrete surface (no text or symbols visible)

Wrangler JL Disassembly Instructions

• Disconnect negative battery terminal of the vehicle.
• If Trailrail equipped - remove three T40 screws and remove rail.
• If Trailrail ready - use panel tool to unclip cover and remove.

Close-up of a black industrial vent with ventilation grilles and a label 'viceh' on the door (no other text or symbols visible)

- Using a panel tool - carefully unclip the tailgate panel and remove.

Red vehicle backrest with black vent grilles and a circular annotation highlighting three red markers (no text or symbols present)

Close-up of a car tire mounted on a vehicle chassis, showing vented grilles and mounting holes (no text or symbols visible)

- With the tailgate panel laying face down, drill two 9/16" holes at the dimples at the bottom of the panel.

Interior view of a car chassis frame with visible structural components and red circular annotations (no text or symbols)

Wrangler JL Installation Instructions

• Install the tailgate panel back into the vehicle by snapping into location.

Close-up of a military vehicle's front panel showing vented seating and tire wheel (no text or symbols visible)

- Install two L brackets, 45mm spacers, and M6 x 60mm flathead screws in the bottom two holes of the tailgate panel with a 4mm Allen wrench.

Close-up of a car rear vent with two red circular markers highlighting the bottom-left corner (no text or symbols visible)

- Loosely install two M6 x 16mm Torx screws with a T40 Torx driver. NOTE - You will tighten in another step.

Close-up of a car tire mounted on a lift in an industrial setting, with two red circles highlighting the components (no visible text or symbols)

Wrangler JL Installation Instructions

- Loosely install (2) M6 x 60mm Hex bolts with 10mm socket.

NOTE - You will tighten in another step.

Close-up of a mechanical component with two red-circled features on its side (no visible text or symbols)

Close-up of a metallic mechanical component with a red circle highlighting a small circular feature (no text or symbols visible)

Close-up of a dark fabric surface with a red circle highlighting a small droplet, possibly indicating a droplet or particle (no text or symbols visible)

- Tighten down the two M6 Torx screws on the bottom of the enclosure with a T40 Torx driver.

Close-up of a hand using a red power strip to test electrical wiring on a car's side panel (no visible text or symbols)

Wrangler JK Installation Instructions

- Remove (4) T20 Torx screws holding the subwoofer in the enclosure. Then disconnect the wiring from the subwoofer.

Close-up of a speaker with exposed wiring and a black speaker cover, partially submerged in a black speaker chamber (no visible text or symbols)

• Install (2) 7mm rubber plugs into the inside of the enclosure.

Close-up of a speaker bowl with MBI QUART branding being inserted, no visible text or symbols on the device itself.

Black plastic container with multiple side slots and red circular markers, placed on a workbench (no text or symbols visible)

Four black plastic pushpins on a white surface (no text or symbols visible)

• Install the white gasket material into the channel of the grill.

Close-up of a black plastic component with white coiled wires and a circular hole, resting on a textured surface (no text or symbols visible)

Coiled white cable on a concrete surface (no text or symbols visible)

Wrangler JK Installation Instructions

- Using panel tool - carefully remove upper tailgate trim panel

Close-up of a vehicle's side panel showing front and rear panels with ventilation grilles (no text or symbols visible)

Close-up of a hand holding a metal frame with visible bolts and components, next to a vehicle tire (no text or symbols)

Wrangler JK Installation Instructions

- Cut out the alignment locations on the template, and then care carefully align and attach the drill template to the tailgate, using the three clip locations as your alignment guide

NOTE: (On the early versions of this template it is best to line up the top of the 3-template alignment holes with the bottom of the panels clip locations. This is done to land your drill points along the center of the brace inside of the tailgate. These braces are indicated by the small spot welds on the tailgate indicated in blue below.)

This template will be adjusted and made available as soon as possible. Contact [e-mail] to receive the updated template or help on verifying where the holes should be.

Close-up of a car front panel with visible ventilation grilles and three yellow circular markers on top (no text or symbols)

Wrangler JK Installation Instructions

- Use a center punch to mark your hole locations.

- Drill (4) 9mm or 23/64" holes at the punched locations.

Tech Tip - Be mindful not to let the drill bit continue to the outer tailgate shell. A drill bit stop collar can be very helpful.

Wrangler JK Installation Instructions

- Installing the provided threaded inserts, We recommend using a threaded insert tool for this.

Close-up of a hand holding a black-handled measuring tool with red base, against a metallic background (no text or symbols visible)

- Place the threaded insert into the previously drilled 9mm or 23/64" hole and squeeze the handle until the threaded insert is completely compressed.

Close-up of a mechanical component with a screwdriver inserted, showing a hole and surrounding surfaces (no text or symbols visible)

Wrangler JK Installation Instructions

- To remove the tool from the threaded insert simply turn the knob at the rear of the tool, to release the threads from within the threaded insert. The threaded insert should remain securely into the hole and not have any play.

Repeat for all four threaded insert locations.

Close-up of a black circular object on a white surface, possibly a button or knob (no text or symbols visible)

- Attach the provided foam patch over the OEM wires near the top of the tailgate.

White car door panel with black cover and ventilation slots, no visible text or symbols

- Hold the empty enclosure up to the tailgate to align the four holes in the enclosure to the threaded insert locations.

Exterior view of a car front bumper with a large cylindrical vent and adjacent dashboard (no visible text or symbols)

- Loosely install the (4) M6x40mm Hex Bolts through the enclosure into the threaded inserts.

Close-up of a dark, textured mechanical component with a circular opening (no visible text or symbols)

Installation Instructions

• Connect the red wire to the + terminal and the black wire to the terminal of the subwoofer.
  • Install the subwoofer with eight ST4.2 x 19mm screws using a T20 Torx.

NOTE: DO NOT OVER TIGHTEN!

Close-up of hands using a tool to connect two metal components on a black textured surface (no visible text or symbols)

• Install the subwoofer grill to the enclosure with six ST4.2 x 19mm screws using a T20 Torx.

NOTE: DO NOT OVER TIGHTEN!

Close-up of a speaker component with a red wire being inserted, showing the MBI QUART logo on its side (no text or symbols on the component itself)

Close-up of a person using a power tool to clean the MBQUART speaker grille (no text or symbols visible on the grille itself)

• Secure subwoofer enclosure wiring along vehicle tailgate wiring using zip ties. After, connect the extension harness and continue to amplifier location and make proper connections.
• Reconnect the negative battery terminal of the vehicle.

Close-up of a car interior showing a black plastic car door, black plastic panel, and red tool (no visible text or symbols)

FCC Notification

This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a mobile installation. This equipment generates uses and can radiate radio frequency energy. If not installed and used in accordance with the instructions, this equipment may cause harmful interference to radio communications. There is no guarantee that interference will not occur in a particular installation.

WARNING: Changes or modifications not expressly approved by the party responsible for compliance could void the user's authority to operate the equipment.

This equipment complied with FCC radiation exposure limits set forth for an uncontrolled environment. This equipment should be installed and operated with a minimum distance of 20cm between the radiator and your body.

MBQuart.com

MUSIC DEFINED

WARRANTY

Maxxsonics, LLC. warrants this product, to the original consumer purchaser, to be free from defects in material and workmanship for a period of one (1) year from the date of purchase. Maxxsonics, LLC. will, at its discretion, repair or replace defective products during the warranty period. Components that prove to be defective in materials and workmanship under proper installation and use must be returned to the original authorized Maxxsonics, LLC. retailer from where it was purchased. A photocopy of the original receipt must accompany the product being returned. The costs associated with removal, re-installation, and freight are not the responsibility of Maxxsonics, LLC. This warranty is limited to defective parts and specifically excludes any incidental or consequential damages connected therewith. To view the full warranty, please visit the website.

MB Quart products are designed and engineered in the USA by

MAXXSONICS®

www.maxxsonics.com