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2013 - 2018 Toyota Avalon
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2013 - 2018 Toyota RAV4
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Original price was $112.50. Current price is $97.45.
Tekonsha T-One connector (also referred to as T-Connector) wiring harnesses are the fastest and easiest way to add an electrical connector to the back of your vehicle. These connectors are used to link the wiring from your vehicle to the trailer when towing. Tekonsha T-One connectors feature custom designs to fit each vehicle make and model based on manufacturer specifications. Plus, the Plug & Play connectors on the end of the wires make it easy to install. No cutting or splicing!
Tekonsha offers the largest, most complete line of T-One connectors. To install a Tekonsha T-One wiring harness, simply locate your vehicle's wiring harness connector typically behind the vehicle taillight - unplug the connection and insert the T-Connector into the vehicle's harness. It's that easy! So what are you waiting for? Hit the road with the peace of mind only Tekonsha can provide. Life's a Journey. Stop Often.
| BRAND: | TEKONSHA |
| PART NUMBER: | 118578 |
| WARRANTY: | LIMITED 1 YEAR WARRANTY |
| WEIGHT: | 1.5 LBS |
| UNIVERSAL OR SPECIFIC FIT: | SPECIFIC |
| CIRCUIT PROTECTED: | YES |
| HARNESS TYPE: | MALE FEMALE |
| TERMINAL QUANTITY: | 4 |
| WIRE COLORS: | BROWN, GREEN, YELLOW, WHITE |
| WIRE QUANTITY: | 4 |
| WIRE GAUGE: | 16 GA. |
| POWER LEAD REQUIRED: | YES |
| ELECTRICAL SYSTEM TYPE: | 3-WIRE SYSTEM |
| HARDWARE INCLUDED: | YES |
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Tekonsha is a leading manufacturer of electronic trailer brake controllers, pioneering the category in the 1970s. The lineup spans proportional units such as the Prodigy P3 and Prodigy iD, time-delayed controllers, the wireless Prodigy RF, plus vehicle-specific wiring harnesses, adapters and trailer brake components engineered for smooth, predictable stopping at any speed.
Tekonsha Engineering Company began in 1964 building RV steps and mirrors. Within a few years it had found its real calling, and by the 1970s Tekonsha was pioneering the manufacture of electronic trailer brake controllers, the product category that still defines the brand. More than half a century later it remains the reference name in trailer braking and is part of the Horizon Global group alongside Reese, Draw-Tite, Fulton, Bulldog and Wesbar.
A brake controller is the component that tells a trailer's electric brakes how hard to work and when, and getting that right is the difference between a controlled stop and a shove from behind. Tekonsha builds both major types. Proportional controllers use an internal accelerometer to sense how quickly the tow vehicle is slowing and apply trailer braking to match, so light braking stays light and hard braking is immediate. Time-delayed controllers ramp to a preset output over a fixed interval, a simpler and more economical approach that suits occasional towing.
The current brake controller range covers most of that ground. The Prodigy iD pairs with a phone through Tekonsha's EDGE technology for setup and monitoring, the P3 offers storable settings for multiple trailers and a trilingual colour LED display, the Prodigy P2 adds a dimmable display and boost mode for heavier loads, and the Voyager keeps operation simple and dependable. The Prodigy RF mounts to the trailer itself and controls wirelessly, which suits rental fleets and drivers who swap tow vehicles.
Installation is supported by vehicle-specific brake control harnesses that plug into a factory connector rather than requiring cut-and-splice wiring, along with mounting brackets and adapters. Matched controller bundles pair a unit with the correct harness. Products are tested to meet and often exceed published industry standards.
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2 compatible vehicles
| Year | Make & Model | Notes |
|---|---|---|
| 2013 - 2018 | Toyota Avalon | Tow Harness T: Connector Assembly Drilling Required Install Time is 60 minutes |
| 2013 - 2018 | Toyota RAV4 | Tow Harness T: Connector Assembly Drilling Required Install Time is 60 minutes |
Yes, the 2013-2018 Toyota Avalon, 2013-2018 Toyota RAV4 Tekonsha Plug & Play T-Connector Adapter Trailer Wiring 118578 (Part #TK118578) is designed to fit the 2013-2018 Toyota Avalon.
The 2013-2018 Toyota Avalon, 2013-2018 Toyota RAV4 Tekonsha Plug & Play T-Connector Adapter Trailer Wiring 118578 (Part #TK118578) fits 2013-2018 Toyota Avalon models. The 2018 model year is the last year covered by this part number. For newer models, check for an updated version.
The 2013-2018 Toyota Avalon, 2013-2018 Toyota RAV4 Tekonsha Plug & Play T-Connector Adapter Trailer Wiring 118578 (Part #TK118578) fits the following vehicles: 2013-2018 Toyota Avalon; 2013-2018 Toyota RAV4. Always verify your specific year, make, and model before ordering.
The 2013-2018 Toyota Avalon, 2013-2018 Toyota RAV4 Tekonsha Plug & Play T-Connector Adapter Trailer Wiring 118578 (Part #TK118578) Drilling is required for installation. Basic hand tools are typically all you need.
The T-Connector is a trailer wiring harness adapter designed for Toyota RAV-4 and Toyota Avalon vehicles. It provides a connection point for trailer lighting by tapping into the vehicle's existing taillight wiring harness on both driver and passenger sides, allowing you to connect a trailer's 4-flat connector without modifying the vehicle's factory wiring.
Yes, the T-Connector (118578-037) is designed for Toyota RAV-4 and Toyota Avalon. The installation process differs slightly between the two models: RAV-4 requires removal of the rear hatch, privacy screen, storage covers, floor covering, and folding the rear seat forward; Avalon requires opening the trunk and partially removing the felt trunk liner behind the taillights.
The manual only confirms compatibility with Toyota RAV-4 and Toyota Avalon. Installation on other models is not addressed in the manual. Contact the manufacturer or a fitment database to confirm compatibility with other vehicles.
Required tools are: Trim Panel Remover, 10mm & 14mm Socket & Ratchet (or 10mm & 14mm Wrench), Drill with 3/32" Drill Bit, 1/4" Socket, Wire Crimpers, Wire Cutters, Philips Head Screwdriver, and Test-probe.
The T-Connector package includes: two T-Connector ends (one with yellow wire for driver side, one with green wire for passenger side), a black converter box with double-sided tape, a white wire with eyelet and screw for grounding, a black 12 ga. power wire, a yellow fuse holder with 15 amp fuse, a yellow butt connector, and cable ties for securing the harness.
Yes. Step 11 requires you to disconnect the vehicle's Negative (-) battery cable before connecting the power wire to the battery. The battery remains disconnected until step 13, when you reconnect the Negative cable after the fuse holder is installed.
For RAV-4: rear hatch, rear threshold plate, privacy screen, storage covers, floor covering, and rear seat (folded forward). For Avalon: trunk and felt trunk liner behind the taillights. Both models require partial removal of rear interior trim panels on driver and passenger sides, and upper side trim panels. Set aside all removed items carefully to avoid damage.
After removing the interior trim panels, locate the taillight wiring harness on both the driver and passenger sides of the vehicle. Separate the connector carefully, being careful not to break the locking tabs. Ensure all connector surfaces are clean and free of dirt before proceeding.
On the driver's side, insert the T-Connector end with the yellow wire between the vehicle's taillight wiring connectors and lock into place, ensuring the connectors are fully inserted with locking tabs in place (step 5). Route the T-Connector with the green wire below the threshold cover to the passenger's side taillight housing and repeat the process (step 6).
On the driver's side, locate a flat surface in an out-of-the-way place and mount the T-Connector's black converter box using the double-sided tape provided (step 7). The location should not interfere with vehicle operation or occupant movement.
Drilling may be required only for the ground connection. Step 8 states you should locate a suitable grounding point such as an existing ground stud, or drill a 3/32" hole if no existing stud is available. Do not drill into the vehicle floor or bed. Always verify what is behind any surface before drilling to avoid damage to the vehicle or personal injury.
A 3/32" drill bit is required if you need to drill a hole for the ground connection (step 8). This hole is used to secure the white ground wire using the eyelet and screw provided.
No. Step 8 explicitly states "Do not drill into vehicle floor or bed." You must locate an existing ground stud or drill into an appropriate surface that is not the floor or bed. Always verify what is behind any surface before drilling.
Clean dirt and rustproofing from the area where you will secure the ground wire (step 8). This ensures a proper electrical connection. Always verify what is behind the surface before drilling to avoid damage to the vehicle or personal injury.
The T-Connector uses four wire colors: yellow wire (driver-side taillight connection), green wire (passenger-side taillight connection), black 12 ga. power wire (connects to vehicle battery positive terminal through fuse holder), and white wire (ground connection). The yellow and green wires tap into the existing taillight harness; the black wire provides power; the white wire provides ground.
Step 10 provides two routing options: (1) Route the black wire through a grommet and along the exterior frame, or (2) Follow the existing wiring along the thresholds into the engine compartment up to the battery. Avoid areas that may pinch or break the wire. If using the grommet route, be careful to avoid hot pipes, heat shields, fuel tank, and other pinch points.
The manual specifies a 15 amp fuse in the English section (step 13). However, the French section references a 10 amp fuse. Verify the correct amperage with the manufacturer before installation, as this discrepancy could affect circuit protection.
Step 12 requires: (1) Remove the fuse from the yellow fuse holder if not already removed, (2) Cut the fuse holder wire, (3) Attach the ring terminal to the vehicle's positive (+) battery cable, (4) Connect the other end of the fuse holder to the black 12 ga. power wire using the yellow butt connector provided. Step 13: Reconnect the Negative battery cable and install the 15 amp fuse into the fuse holder.
The black power wire is 12 ga. (12 gauge), as stated in steps 9 and 12.
Step 14 requires securing the remainder of the T-Connector harness with the cable ties provided to prevent damage or rattling. Be careful to avoid any areas that would pinch, cut, or melt the wire. Do not pinch the harness in the door latch when routing the 4-flat connector through the driver's side trim panel.
Route the 4-flat connector through the driver's side trim panel into the side storage compartment and store it there when not in use (step 14 note). When in use, pull the 4-flat through the door and close it. Be careful not to pinch the harness in the door latch.
Always wear safety glasses and use all safety precautions during installation. Before drilling, verify what is behind any surface to avoid damage to the vehicle or personal injury. Do not drill into exposed surfaces. When routing the power wire, avoid hot pipes, heat shields, fuel tank, and pinch points. Do not pinch the harness in the door latch. Read and follow all warnings printed on the tow vehicle's battery.
Do not exceed the lower of: (1) the towing manufacturer's rating (including in your vehicle owner's manual), or (2) the specific amperage ratings stated on the product. The manual does not specify the product's amperage rating; check the product label or contact the manufacturer. Overloading circuits can cause fires.
Step 13 warning states: All connections must be complete for the T-Connector to function properly. Test and verify installation with a test light or trailer once installed. For the initial test, reset the vehicle electrical system by temporarily removing the key from the ignition.
Step 15 requires reinstalling the plastic trim panels, threshold, cargo trays, tail lamps, and other items removed during installation, being careful not to pinch or cut the wires. Ensure all connections are complete and test the installation with a test light or trailer to verify proper function.
Yes, the T-Connector (118578-037) is designed for Toyota RAV-4 and Toyota Avalon vehicles. Installation procedures differ slightly between the two models.
You need: Trim Panel Remover, 10mm & 14mm Socket & Ratchet (or wrench), Drill with 3/32" Drill Bit, 1/4" Socket, Wire Crimpers, Wire Cutters, Philips Head Screwdriver, and Test-probe.
Yes, disconnect the vehicle's Negative (-) battery cable before connecting the power wire to the battery (step 11). Reconnect it after the fuse holder is installed (step 13).
The English manual specifies a 15 amp fuse; the French section references 10 amp. Verify the correct rating with the manufacturer before installation.
Step 13 warning states: All connections must be complete for the T-Connector to function properly. Verify that: (1) both T-Connector ends are fully inserted into the taillight harness connectors with locking tabs in place, (2) the black power wire is properly connected to the battery positive terminal through the fuse holder, (3) the white ground wire is securely fastened, (4) the 15 amp fuse is installed in the fuse holder, and (5) the Negative battery cable is reconnected. Test with a test light or trailer and reset the vehicle electrical system by temporarily removing the ignition key.
Step 4 requires that all connector surfaces be clean and free of dirt before connecting. Step 5 requires that connectors be fully inserted with locking tabs in place. If connectors are not locking, clean the connector surfaces thoroughly and ensure you are inserting them completely until the locking tabs engage.
Step 10 warning states: If routing the wire through a grommet and along the exterior of the vehicle, be careful to avoid hot pipes, heat shields, fuel tank, or other points that may pinch or break the wire. Step 14 requires securing the harness with cable ties to prevent damage and avoid areas that would pinch, cut, or melt the wire. Reroute the wire away from heat sources and secure it properly with cable ties.
Total for 4 items:
$173.40$188.45
Ann
Ordered online. Shipment arrived on time and with all the correct parts. Great customer service and friendly staff. Also, pricing was great!
May 22, 2023
