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Vehicle battery connection required
Includes fuse holder, battery connection wiring and other necessary wiring components
Includes fuse holder, battery connection wiring and other necessary wiring components
Warranty: One-Year Limited Warranty
Electrical System Type: 3W
Output Type: 4-Way Flat
Tail Light Circuits: 6.0 Amps
Turn and Brake Circuits: 3.0 Amps
Installation Difficulty: Professional
Installation Time Exact (Minutes): 45
If your vehicle is not equipped with wiring for towing a trailer, CURT custom wiring is the ideal solution. A custom wiring harness -- also called a T-connector -- is a simple, plug-and-play electrical device that plugs into your automotive electric system and provides a standard, universal trailer wiring connection. This is done using two or more vehicle-specific, OEM-compatible connectors to plug into the taillight assembly, eliminating the need for cutting, splicing and soldering during installation. Custom wiring harnesses are made vehicle-specific, and while they are not available for all vehicles, they do offer one of the fastest, easiest and most secure ways to wire a vehicle for towing. This particular plug-in harness provides a 4-way flat connector socket and is designed to be a custom wiring harness to fit certain years of the Mazda CX5 (to verify your vehicle compatibility, see application info). It comes with all necessary wiring components to establish a reliable trailer wiring connection, as well as a dust cover to keep the connector clean when not in use. You have a picture in mind of your next destination -- maybe it's the boat landing at your favorite fishing spot, maybe it's a campsite that overlooks one of nature's masterpieces, or maybe it's the next big jobsite. However, turning that picture into a reality takes more than just daydreaming. It takes a solid connection and the right amount of power. CURT custom wiring is made with some of the most sophisticated technology in the industry and is designed to install with ease, giving you a long-lasting electrical connection for your towing hitch setup.
CURT offers a variety of high-quality trailer hitches and accessories for select vehicle models. Find the perfect fit for your towing needs at TowUniverse.
CURT, a Lippert brand, offers a complete line of towing products and is the leading manufacturer of custom-fit trailer hitches. We offer the broadest selection of custom-fit hitches, and each one is designed, welded, and coated in Wisconsin.
CURT is also a leader in flat towing products, as well as 5th wheel, gooseneck, and weight distribution hitches, ball mounts, electrical components, cargo solutions, and other towing accessories.
For everything from passenger cars and vans to full-size pickups and SUVs, CURT is 'The First Name in Towing Products®.'
Experts available to answer your questions
Call 888-634-94941 compatible vehicles
| Year | Make & Model | Notes |
|---|---|---|
| 2017 - 2021 | Mazda CX-5 | Installation Time: 30-60 minutes |
The CURT 56377 Vehicle-Side Custom 4-Pin Trailer Wiring Harness, Fits Select Mazda CX-5 (Part #BKDK56377) fits 2017-2021 Mazda CX-5 models. The 2021 model year is the last year covered by this part number. For newer models, check for an updated version.
Yes, the CURT 56377 Vehicle-Side Custom 4-Pin Trailer Wiring Harness, Fits Select Mazda CX-5 (Part #BKDK56377) is designed to fit the 2017-2021 Mazda CX-5.
The CURT 56377 Vehicle-Side Custom 4-Pin Trailer Wiring Harness, Fits Select Mazda CX-5 (Part #BKDK56377) fits the following vehicles: 2017-2021 Mazda CX-5. Always verify your specific year, make, and model before ordering.
The CURT 56377 Vehicle-Side Custom 4-Pin Trailer Wiring Harness, Fits Select Mazda CX-5 (Part #BKDK56377) Typical installation time is 30-60 minutes. Basic hand tools are typically all you need.
Yes, the Curt 56377 is designed for Mazda CX-5 SUVs. It is compatible with the vehicle's taillight wiring system and interior trim configuration shown in the installation guide.
The harness has two circuit ratings: Signal Circuits are rated at 3.0 amps per side, and Tail/Running Circuits are rated at 6.0 amps total. Do not exceed these ratings or the tow vehicle lamp load rating, whichever is lower, as exceeding the rating can cause loss of warranty, overheating and potential fire.
The battery connection must be fuse-protected with a maximum 10-amp fuse. Do not exceed this rating, as it can cause loss of warranty, overheating and potential fire.
Required tools are: ratchet, ratchet extension, 10mm socket, Phillips screwdriver, flat blade screwdriver, wire stripper, wire crimper, and cutting tool. A panel trim removal tool is also needed to remove the interior side trim panel without damage.
The manual does not specify whether the battery must be disconnected before installation. Contact the vehicle manufacturer or Curt Manufacturing for this safety requirement.
Open the rear hatch and remove all floor coverings and storage trays. Remove the rear scuff panel by removing its fasteners, then pulling out at the bottom and up. On each side, remove the interior side trim panel by first removing: the push fastener and cargo tie down at the rear, the fastener from the rear seat release handle, the Phillips screw at the front upper side, and the cargo tie down at the front lower end. Use a panel trim removal tool to remove the trim panel itself.
Locate the vehicle taillight wiring harness connectors behind the side trim panel. Separate the connectors from the taillight housing, taking care not to damage the locking tabs. Insert the custom wiring harness end with the yellow wire between the separated connectors. Make sure the connectors are fully inserted with locking tabs in place. Repeat this process on the passenger side using the harness end with the green wire.
Locate a suitable grounding point near the taillight connector, such as an existing screw with nut in the vehicle frame. If no suitable point exists, drill a 3/32" pilot hole for the provided screw. Clean the area of rust, dirt and paint. Secure the white ground wire using the ring terminal and provided screw.
Drilling may be required. If a suitable existing screw with nut is not available as a grounding point near the taillight connector, you must drill a 3/32" pilot hole for the provided ground screw. Before drilling, check for miscellaneous items that may be hidden behind or under any surface to avoid damage and personal injury.
Locate a flat spot inside the vehicle near the taillight and adhere the black converter box using the provided double-sided tape.
Route the black power wire from the vehicle battery as shown on the included CME-PCL-INS sheet. Refer to that sheet for specific routing instructions.
When not in use, roll up the 4-flat connector and store it in a convenient, out-of-the-way location inside the trunk. When in use, route it to the center of the vehicle and out of the trunk. Secure any loose wires with the provided cable ties.
All steps must be followed to ensure the wiring harness functions properly. Once installed, test for proper function by using a test light or connecting a properly wired trailer.
The harness includes: custom wiring harness ends with yellow and green wires, a white ground wire with ring terminal, a provided ground screw, a black converter box, double-sided tape for mounting the converter box, a 4-flat dust cover, cable ties for securing loose wires, and the CME-PCL-INS sheet for battery power wire routing instructions.
Reinstall all items removed during installation, including floor coverings, storage trays, rear scuff panel, and interior side trim panels. Install the provided 4-flat dust cover to help prevent corrosion. Test the harness for proper function using a test light or a properly wired trailer.
Yes, the Curt 56377 is designed for Mazda CX-5 SUVs and is compatible with the vehicle's taillight wiring system.
A 10-amp maximum fuse is required for the battery connection. Do not exceed this rating.
You need a ratchet, ratchet extension, 10mm socket, Phillips and flat blade screwdrivers, wire stripper, wire crimper, cutting tool, and a panel trim removal tool.
Signal Circuits are rated at 3.0 amps per side; Tail/Running Circuits are rated at 6.0 amps total. Do not exceed these ratings or the tow vehicle lamp load rating.
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