CURT ECN9358 Custom Towed Vehicle RV Wiring Harness Installation Guide

ECN9358 Custom Towed Vehicle RV Wiring Harness
Installation Guide

Level of Difficulty

Moderate
Installation difficulty levels are based on time and effort involved and may vary depending on the installer level of expertise, condition of the vehicle and proper tools and equipment.
Wiring Location(s)
S1 and S2
*Wiring Location Guide for SUVs and Vans (S)**

• Representative vehicle shown

Tools Required

WARNING
Do not exceed product rating or tow vehicle lamp load rating, whichever is lower.
Product Photo

NOTICE
Before you begin installation, read all instructions thoroughly.
Proper tools will improve the quality of installation and reduce the time required.
All steps must be followed to ensure the product will function properly. Once installed, test for proper function by using a test light or connecting a properly wired trailer.

Maintenance

Periodic inspection of all wires and connections should be performed to ensure there is no visible damage or loose connections.
Step 1
Locate the vehicle battery in the engine compartment on the driver side and disconnect the negative battery terminal. Be sure to fasten this wire down and away from the battery while completing the installation process.

Step 2
Open the rear hatch and use a flat blade screwdriver to open the taillight fastener covers. Use a T-27 Torx bit to remove the screws
Note: Be careful to not lose the screws between the vehicle trim and taillight. The fasteners could end up  above the bumper or fall all the way through to the floor.

Step 3
Remove the taillight by pulling straight back.
Locate the taillight housing and separate the connectors, taking care not to damage the locking tabs. Set aside for later reinstallation.
Repeat on the other side of the vehicle.

How to Fishwire

A) Fish wire is a way to push or pull an electrical wire through a blind hole. Make sure the wire is long enough to stick out on the other side. Insert the fish wire through the blind hole and locate it on the other side.
B) Use tape to secure the harness to the fish wire and pull back up.
The fish wire or harness may get hung up on something, if this happens you may have to push back down, wiggle it around or twist the wire to loosen it from what it’s hung up on.
Fish wire could be anything from a cut-up wire hanger, stiff wire, rope or string depending on what is needed for the installation.

Step 4
Route a Fishwire down between the bumper cover and the body of the vehicle. Repeat this step on the other side of the vehicle.

Step 5
Starting on the driver side, locate the housing with the yellow wire on the RV wiring harness. From under the vehicle bumper, secure this to the Fishwire and pull the harness up to the taillight cavity.
Secure the RV harness to the vehicle factory wiring and secure to the taillight. Set the taillight inside the taillight cavity, but do not fully install at this time.

Step 6
Route the housing with the green wire above the bumper mount and along the bumper to the passenger side. Zip tie as needed along the bumper. Route above the passenger side bumper mount and repeat step 5 to the housing with the green wire.

Step 7
On the driver side, locate a grounding point such as an existing screw or bolt in the frame of the vehicle or drill a 3/32″pilot hole.
The area should be free from rust, dirt, and paint (abrasive pad/paper to remove rust and paint). Secure the white ground wire with the ring terminal on the existing fastener or with the provided ground screw.
CAUTION
Check for miscellaneous items that may be hidden behind or under any surface before drilling to avoid damage and/or personal injury

Step 8
Reinstall the taillights and tighten the zip ties on the green wire. Secure any excess wire so that it is not drooping or dangling, but not so tight that it causes unnecessary strain to the wire which could lead to breakage over time.
NOTICE
Once the RV harness is installed, verify that the harness is functioning by attaching the 4-flat to any vehicle with functioning trailer lights. The taillights on the tow vehicle should function along with the taillights on the towing vehicle.
Step 9
Route the 4-flat along the frame above the rear suspension and along the fuel tank.  Loosely secure any excess wire so that it is not drooping or dangling and tighten later.

Step 10
Route along the fuel lines to the front of the vehicle until you reach the rear of the front tire. Route the 4-flat to the vehicle wheel well and from the engine compartment drop a fish wire down between the inner and outer front fender. Pull the 4-flat up between the inner and outer fender.

Step 11
Continue to route the 4-flat by turning the rubber gasket and routing under this gasket and along the driver-side inner fender and to the front of the vehicle.
Secure any excess wire so that it is not drooping or dangling, but not so tight that it causes unnecessary strain to the wire which could lead to breakage over time. After removing slack from the 4-flat wire, tighten any zip ties and add as needed.
Use a zip tie to fasten any excess wire to a solid spot along the driver-side inner fender. Reinstall all items removed during install. If it was disconnected at the beginning of the installation, reconnect the negative battery terminal. Install  the provided 4-flat dust cover to help prevent corrosion.

58997-INS-RA • 04/05/2022 • ECN9358 • PAGE 5 OF 5

Read User Manual Online (PDF format)

Read User Manual Online (PDF format)  >>

Download This Manual (PDF format)

Download this manual  >>