Ask a Question About This Product
Our in-house experts typically reply within one business day.
Our in-house experts typically reply within one business day.
CURT
On Sale Today
Original price was $538.90. Current price is $382.34.You save $156.56 (29%)
Free Shipping
Ships free on all orders
Authorized Dealer2024 - 2025 Lincoln Nautilus
Confirmed to Fit
Always the correct part
We know our products
Quality Products
Free Shipping!
Always the correct part
We know our products
Quality Products
Free Shipping!
Verify Fitment
Select your vehicle to confirm this part fits.
Quick Ship
In stock and ready to ship — order now!
FREE ShippingFREE SHIPPING
Estimated delivery Mon, Aug 24 - Thu, Aug 27
Order before 2 PM EST Monday–Friday for same-day processing
Guaranteed safe & secure checkout
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 888-634-9494Limited Lifetime (One-year finish, one-year parts)
The CURT 59236 is a powered taillight converter that converts your vehicle's taillight signals to a 4-flat trailer connector. It allows you to connect a trailer with a 4-flat plug to your vehicle's existing taillight wiring. The converter reads your vehicle's brake, turn, and tail light signals and outputs them through the 4-flat connector for the trailer to use.
The CURT 59236 is designed for SUVs, vans, passenger cars, and trucks with 12-volt negative ground electrical systems. The manual provides wiring location guides for three vehicle types: SUVs and vans (S), passenger cars (P), and trucks (T). You must verify your vehicle has a 12-volt negative ground system before installation. Consult your vehicle's owner's manual to confirm your electrical system type.
The CURT 59236 works with four vehicle wiring types: two-wire (combined stop and turn signal with independent tail signal), three-wire (independent stop, turn and tail signals), PWM-ST (combined stop and tail signal with independent turn signal), and PWM-STT (combined stop, turn and tail signal). You must identify your vehicle's wiring type before installation by probing the taillight connectors with a multimeter or test light while activating each light circuit. The manual provides a detailed chart on page 2 to help you determine your vehicle's wiring type.
Required tools are: test light, utility knife, electrical tape, wire crimper, paper, wire stripper, and pen. You may also need a multimeter (as an alternative to a test light) to determine your vehicle's wiring type. A drill with a 3/32" bit is needed if you must create a new grounding point, and a screwdriver is required to secure the ground wire. Proper tools will improve installation quality and reduce installation time.
The CURT 59236 includes: a black converter box, a white ground wire with ring terminal, a 12-gauge power wire with ring terminal, snap locks for connecting input wires to vehicle harness, provided cable ties, double-sided tape for mounting the converter, a screw for the ground wire connection, a 4-flat dust cover, and a fuse holder with 15-amp maximum fuse. The manual shows a hardware photo on page 1 for reference.
Yes, you must disconnect the negative battery terminal before beginning installation. This is a required safety step. Look up the battery location in your vehicle's owner's manual. Be sure to fasten the disconnected negative wire down and away from the battery during the installation process. Reconnect the negative battery terminal only after all other installation steps are complete.
With the vehicle running and all lights off at the back, probe the taillight connectors (still connected to the vehicle) using a multimeter set to DC volts or a test light. Ignore any wires carrying less than two volts (multimeter) or that do not illuminate the test light bulb. Then activate each light circuit (left turn, right turn, brakes, tail) one at a time and probe the remaining wires. Match your results to the chart on page 2 titled 'Determining Vehicle Wiring Types' to identify whether your vehicle is two-wire, three-wire, PWM-ST, or PWM-STT. This determines which converter wires connect to which vehicle wires.
Use the snap locks provided to attach the converter's input wires to your vehicle's taillight harness wires. The connection depends on your vehicle's wiring type. For two-wire systems: green wire to right stop/turn, red wire to ground (white wire), yellow wire to left stop/turn, brown wire to tail. For three-wire: green to right turn, red to stop, yellow to left turn, brown to tail. For PWM-ST: green to right turn, red to stop/tail, yellow to left turn, brown to ground. For PWM-STT: green to right turn/stop/tail, red to ground, yellow to left turn/stop/tail, brown to ground. Refer to the Wiring Installation table on page 3.
Mount the black converter box on a flat spot inside the vehicle near the taillight using the provided double-sided tape. The area should be clean and suitable for adhesive mounting. Ensure the location allows easy access to the wires and does not interfere with vehicle operation or maintenance.
Locate a suitable grounding point near the converter, such as an existing screw with nut in the vehicle frame. The area must be free of rust, dirt, and paint. Secure the white ground wire using the ring terminal and the provided screw. If no suitable existing screw is available, drill a 3/32" pilot hole in a clean area of the vehicle frame and use the provided screw. Before drilling, check for hidden items behind or under any surface to avoid damage and personal injury.
Route the 12-gauge power wire from the converter to the vehicle battery location, avoiding pinch points and hot or rotating components. Use existing grommets or add a grommet when passing the wire through sheet metal to protect it from sharp edges; alternatively, use silicone for protection. At the battery, attach the ring terminal of the black power wire to the positive (+) battery terminal using a butt connector. Install the fuse holder with a 15-amp maximum fuse after all other steps are complete. The battery connection must be fuse-protected with a maximum 15-amp fuse to prevent overheating and potential fire.
Install the 15-amp fuse in the fuse holder only after all other installation steps are complete. This is the final step before testing. The fuse protects the battery connection and converter from overcurrent. Do not exceed a 15-amp fuse rating.
When in use, route the 4-flat connector to the center of the vehicle and out of the trunk. When not in use, roll up the connector and store it in a convenient, out-of-the-way location inside the trunk. Secure any loose wires with the provided cable ties to prevent tangling and damage. Install the provided 4-flat dust cover to help prevent corrosion.
Drilling is required only if you cannot find a suitable existing grounding point (such as an existing screw with nut in the vehicle frame) near the converter. If you must drill, create a 3/32" pilot hole in a clean area of the vehicle frame free of rust, dirt, and paint. Before drilling, check for hidden items behind or under any surface to avoid damage and personal injury. The modification is permanent.
The CURT 59236 has the following electrical ratings: signal circuits (left and right turn) are rated at 5.0 amps per side, and tail/running circuits are rated at 7.5 amps total. Do not exceed the product rating or your tow vehicle's lamp load rating, whichever is lower. Exceeding the product rating can cause loss of warranty, overheating, and potential fire. The product is designed for 12-volt negative ground systems only.
The power wire is 12-gauge (12 GA) or larger. This wire connects from the converter to the vehicle battery and must be routed carefully to avoid pinch points and hot or rotating components.
The maximum fuse rating is 15 amps. The battery connection must be fuse-protected with a 15-amp maximum fuse. Do not use a fuse larger than 15 amps, as exceeding the product rating can cause loss of warranty, overheating, and potential fire.
The converter has four input wires: green (right turn), red (brake), yellow (left turn), and brown (taillight). These wires connect to your vehicle's corresponding taillight signals using snap locks. The white ground wire connects to vehicle ground. The black power wire connects to the vehicle battery positive terminal. The specific connections depend on your vehicle's wiring type (two-wire, three-wire, PWM-ST, or PWM-STT).
Test the converter using either a test light or a trailer. With a test light: attach the ground lead to the exposed ground terminal of the 4-flat end, then activate the tow vehicle's left turn, right turn, tail, and brake lights one at a time. Probe the three receptacles of the 4-flat end to confirm proper functionality. With a trailer: mate the 4-flat with the trailer and run the same test using the trailer lights. If a trailer light function does not work, disconnect the trailer 4-flat, turn vehicle functions off, and recheck with a test light. If the test light shows good functionality, the issue is with the trailer, not the converter.
Do not exceed the CURT 59236 product rating or your tow vehicle's lamp load rating, whichever is lower. The product has signal circuit ratings of 5.0 amps per side and tail/running circuit ratings of 7.5 amps total. Exceeding these ratings can cause loss of warranty, overheating, and potential fire. Consult your vehicle owner's manual or contact the vehicle manufacturer for your vehicle's lamp load rating.
Before drilling, check for miscellaneous items that may be hidden behind or under any surface to avoid damage and personal injury. This includes fuel lines, electrical wiring, brake lines, and other components that could be damaged if drilled through. Take time to inspect the area thoroughly before making any holes.
When passing the 12-gauge power wire through sheet metal, use an existing grommet, add a new grommet, or apply silicone to protect the wire from sharp edges. This prevents the wire insulation from being cut or abraded, which could cause a short circuit or fire hazard.
After installation, perform the following checks: (1) Test the converter using a test light or trailer to confirm all light functions work properly (left turn, right turn, brake, tail). (2) Verify that the converter box is securely mounted with double-sided tape. (3) Confirm the ground wire is securely fastened with the ring terminal and screw. (4) Check that the power wire is properly routed and secured with cable ties, avoiding pinch points and hot components. (5) Verify the 15-amp fuse is installed in the fuse holder. (6) Ensure all loose wires are secured with cable ties. (7) Reinstall all items removed during installation.
Periodic inspection of all wires and connections should be performed to ensure there is no visible damage or loose connections. Check the converter box mounting, ground wire connection, power wire routing, and all snap lock connections. Look for signs of corrosion, especially on the 4-flat connector. Install and maintain the provided 4-flat dust cover to help prevent corrosion when the connector is not in use.
Pulsing trailer lights every two seconds indicate that the lamp circuits exceed the product's ratings (5.0 amps per side for signals, 7.5 amps total for tail/running) or there is a wiring issue with the trailer. The converter's short circuit, overload, and thermal protection activate to prevent damage. Check that your vehicle's lamp load does not exceed the converter's ratings. If the vehicle lights are within rating, disconnect the trailer and inspect its wiring for faults or excessive lamp loads.
First, disconnect the trailer 4-flat connector from the vehicle. Turn off the corresponding light function on the vehicle (left turn, right turn, brake, or tail). Use a test light to probe the 4-flat receptacles to check if the converter is sending the signal. If the test light shows the signal is present, the problem is with the trailer wiring or lights, not the converter. If the test light shows no signal, recheck your vehicle wiring type identification and verify that the converter input wires are correctly connected to the vehicle taillight harness using the Wiring Installation table on page 3.
Check that the 15-amp fuse is installed in the fuse holder and is not blown. Verify that the black power wire is securely connected to the vehicle battery positive (+) terminal using the ring terminal and butt connector. Confirm that the white ground wire is securely fastened to a clean, rust-free grounding point on the vehicle frame using the ring terminal and screw. Ensure the negative battery terminal is reconnected. If the fuse is blown, check for a short circuit in the power wire routing or a wiring error in the converter connections.
The CURT 59236 fits SUVs, vans, passenger cars, and trucks with 12-volt negative ground electrical systems. You must identify your vehicle's wiring type (two-wire, three-wire, PWM-ST, or PWM-STT) using the test procedure on page 2 before purchase. Consult your vehicle owner's manual to confirm your electrical system type.
Yes, you must disconnect the negative battery terminal before beginning installation and reconnect it only after all other steps are complete.
Perform periodic inspection of all wires and connections to ensure no visible damage or loose connections. Maintain the 4-flat dust cover to prevent corrosion.
The CURT 13613 has a gross trailer weight (GTW) capacity of 3,500 lbs and a tongue weight (TW) capacity of 350 lbs. Never exceed your vehicle manufacturer's recommended towing capacity.
Required tools are: ratchet, tape measure, torque wrench, masking tape, 7mm socket, 10mm socket, 11/16" socket, reciprocating saw, tin snips, exhaust stand, exhaust isolator removal tool, and 7/16" fishwire (8 qty included). A 5/8" open end wrench and pry bar are also needed for rubber isolator removal if an exhaust hanger removal tool is not available. For a full tools reference guide, visit curtmfg.com/trailer-hitch-installation.
Yes. The kit includes 8 carriage bolts (7/16"-14 x 1-3/4"), 8 serrated-flange nuts (7/16"-14), 8 spacers (0.25" x 1.00" x 2.50"), and 8 fishwires (7/16").
Installation requires: partial removal and trimming of the underbody panel and heat shield; temporary lowering of the exhaust; trimming of the lower bumper cover (approximately 2" from the edge and 1-3/4" from center on each side, totaling 3-1/2" width); and removal of two metal tabs from the end of the frame rails using a reciprocating saw or angle grinder to make the flange straight. The heat shield is reinstalled after hitch mounting, and underbody panels are reinstalled either as-is or trimmed slightly (approximately 3-1/4" x 3/4") to fit around the hitch.
No drilling is required. The installation uses existing frame rail holes and access holes. However, a reciprocating saw or angle grinder is needed to remove two metal tabs from the frame rails and to trim the lower bumper cover.
Measure and mark 2" from the edge of the lower bumper cover and 1-3/4" from center on each side (3-1/2" total width) for trimming. Use a reciprocating saw to trim the marked area to allow clearance for the receiver hitch. The dimensions are approximate; adjust as required for your specific vehicle.
Yes. The exhaust must be temporarily lowered by unhooking three rubber isolators: two by the muffler and one towards the front of the vehicle. Be sure to support the exhaust when removing the isolators to prevent damage. The exhaust is raised back into position and the isolators are reattached after the hitch is mounted.
Two methods are available. If you have an exhaust hanger removal tool, use it to remove the isolators. Alternatively, use a 5/8" open end wrench and a pry bar: slide the wrench up to the rubber isolator, cradling the hanger rod, place the flat edge of the pry bar between the wrench and the hanger stop or rod, then rotate the pry bar toward the wrench to remove the isolator. Using a lubricant or soapy water on the hanger rod and rubber isolator helps removal.
Remove the two fabric underbody side panels by removing three screws from the lower edge with a 7mm socket and two washer nuts from the upper edge with a 10mm socket. Set the panels aside for reinstallation later. After hitch installation, reinstall them either as-is or trim them slightly (approximately 3-1/4" x 3/4") to fit around the hitch as needed.
Remove the rearmost exhaust heat shield by removing four screws located in the lower bumper cover flange with a 7mm socket and two washer nuts above the muffler with a 10mm socket. Set the heat shield aside for reinstallation later. After the hitch is mounted, reinstall the heat shield, slightly bending as needed to provide clearance for the hitch receiver.
Before trimming the lower bumper cover, pull the kick sensor wires up and away from the cutting area to prevent damage during the trimming process.
The fishwire technique guides fasteners through frame rails without losing them. Insert the coiled end of the fishwire tool through the hitch mounting hole in the vehicle frame rail and out the access hole. Pass the coiled end through a spacer and thread a carriage bolt into the coil. Kink the wire to keep the spacer separate from the bolt. Pull the fishwire, spacer, and bolt through the frame and out the mounting hole. Use the fishwire to guide the hitch during mounting and prevent loss of bolts or spacers inside the frame rail. Eight fishwires are included.
Raise the hitch into position with the exhaust hanger mount sliding into the notch in each side plate. Thread the four fishwires into the mounting holes. Remove the fishwires one by one and finger tighten the 7/16" serrated flange nuts to hold them in place.
Using tin snips, make two cuts in the center of the heat shield. Bend the area between the cuts further so it is bent back onto itself. This allows the heat shield to be reinstalled with clearance for the hitch receiver.
1. Fishwire two carriage bolts and spacers from the large access hole into the bottom round holes in the frame rail on each side, leaving all four fishwires attached. 2. Raise the hitch into position with the exhaust hanger mount sliding into the notch in each side plate. 3. Thread the four fishwires into the mounting holes and remove them one by one, finger tightening the 7/16" serrated flange nuts. 4. Fishwire the four remaining carriage bolts and spacers into the mounting holes on the side of the frame rail. 5. Remove the fishwires one by one and loosely install the remaining serrated flange nuts. 6. Torque all 7/16" fasteners to 49 ft-lbs.
Torque all 7/16" fasteners (carriage bolts and serrated-flange nuts) to 49 ft-lbs.
The hitch uses 8 carriage bolts, 7/16"-14 x 1-3/4". They are torqued to 49 ft-lbs.
The hitch uses 8 spacers with dimensions 0.25" x 1.00" x 2.50".
The hitch uses 8 serrated-flange nuts, 7/16"-14. They are torqued to 49 ft-lbs.
Periodic inspection of the trailer hitch should be performed to ensure all mounting hardware remains tight and structural components are secure.
Safety glasses should be worn at all times while installing this product. Support the exhaust when removing isolators to prevent damage. Pull kick sensor wires up and away from the cutting area before trimming the bumper cover to prevent damage. Never exceed the vehicle manufacturer's recommended towing capacity.
The installation difficulty level is Moderate. Installation difficulty levels are based on time and effort involved and may vary depending on the installer's level of expertise, condition of the vehicle, and proper tools and equipment.
Visit www.curtmfg.com for a full-color copy of the instruction manual, helpful videos, guides, and more. For product support, call 877.287.8634. For a tools reference guide, visit curtmfg.com/trailer-hitch-installation. For towing safety information, visit curtmfg.com/understanding-towing.
To register your purchase, get copies of product warranties, or provide feedback, visit warranty.curtgroup.com/surveys. CURT stands behind its products with industry-leading warranties.
1 compatible vehicles
| Year | Make & Model | Notes |
|---|---|---|
| 2024 - 2025 | Lincoln Nautilus | — |
No reviews have been added for this product.
