1998 Jeep Grand Cherokee Trailer Wiring Diagram

If you own a 1998 Jeep Grand Cherokee, you may have encountered the need to connect a trailer to your vehicle for various purposes. To do so, you need to have the right wiring system set up that can power the trailer’s lights and brakes. In this article, we will provide you with a comprehensive guide on the 1998 Jeep Grand Cherokee trailer wiring diagram.


The 1998 Jeep Grand Cherokee is equipped with a standard towing package that includes a four-pin trailer connector. However, if you plan to use your vehicle for frequently towing heavy trailers, you will need a seven-pin connector that offers additional features, such as a brake controller circuit, backup lights, and 12-volt power supply.

Components of the Wiring System

The wiring system for the 1998 Jeep Grand Cherokee consists of several components, including:

Component Description
Trailer Connector A device that connects the trailer’s wiring to the vehicle’s electrical system.
Wiring Harness A set of wires that connects the trailer connector to the vehicle’s battery, lights, and brakes.
Fuses and Relays Devices that protect the wiring system from electrical overload and short circuits.

Step-by-Step Wiring Guide

Step 1: Gather the Required Tools and Materials

Before you start wiring your vehicle for towing, you need to gather the following tools and materials:

  • Screwdriver and pliers
  • Wire cutters and strippers
  • Electrical tape and zip ties
  • Wiring harness
  • Trailer connector
  • Fuses and relays (if needed)

Step 2: Install the Wiring Harness

The wiring harness is the backbone of the towing system. It connects the trailer connector to the power source and lighting system of the vehicle. Follow the steps below to install the wiring harness:

  1. Locate the vehicle’s battery and disconnect the negative terminal.
  2. Find the wires that connect the taillights and brake lights to the vehicle’s electrical system. Cut these wires and strip off their insulation.
  3. Insert the stripped ends of the wires into the corresponding slots on the wiring harness. Secure them in place with electrical tape or zip ties.
  4. Route the wiring harness along the vehicle’s frame and attach it with zip ties or clamps.
  5. Reconnect the negative battery terminal and test the wiring harness with a test light or multimeter to ensure that the connections are working properly.

Step 3: Install the Trailer Connector

The trailer connector is the link between the wiring harness and the trailer. It provides power to the trailer’s lights and brakes. Follow the steps below to install the trailer connector:

  1. Mount the trailer connector on a flat and stable surface on your vehicle’s rear bumper.
  2. Locate the wires on the trailer connector and match them with the corresponding wires on the wiring harness.
  3. Insert the wires into the appropriate slots on the trailer connector and secure them in place with screws or clips.
  4. Test the trailer connector using a test light to make sure it is properly connected.

Step 4: Install Fuses and Relays (if needed)

If you are using a seven-pin trailer connector, you will need to install fuses and relays to protect the wiring system from electrical overload and short circuits. Follow the steps below to install them:

  1. Locate the fuse box and the relay panel on your vehicle. They are usually located under the hood or in the trunk.
  2. Find the fuses and relays that correspond to the brake controller, backup lights, and other features of the trailer connector that you are using.
  3. Insert the fuses and relays into their designated slots and secure them properly.
  4. Test the electrical system to ensure that the fuses and relays are working properly.


1. How do I know if I need a four-pin or seven-pin trailer connector?

If you plan to tow a small trailer that has basic lighting features, such as taillights, running lights, and turn signals, a four-pin trailer connector should suffice. However, if you are towing a large trailer that has additional features, such as backup lights, brake controller, and 12-volt power supply, you will need a seven-pin connector.

2. How do I find the location of the fuse box and relay panel on my vehicle?

The location of the fuse box and relay panel may vary depending on the make and model of your vehicle. Consult the owner’s manual or check the manufacturer’s website for more information. You can also ask a certified mechanic for assistance.

3. How do I test the electrical system after installing the wiring system?

You can test the electrical system by connecting a test light or multimeter to the wiring harness and trailer connector. Check if the lights on the trailer are working properly and if there are any signs of electrical overload or short circuits. It is recommended to conduct a test before you start towing to avoid any mishaps on the road.

4. Can I install the wiring system myself or do I need to hire a professional?

If you have basic electrical knowledge and experience, you can install the wiring system yourself. However, if you are not confident in your abilities, it is recommended to seek the assistance of a certified mechanic or professional installer to ensure that the system is installed safely and securely.

5. How often do I need to inspect my wiring system for maintenance?

It is recommended to inspect your wiring system for wear and tear and other issues before each towing trip. Regular maintenance can ensure that the system is working properly and prevent any potential problems on the road. If you notice any signs of damage or malfunctions, you should have the system repaired or replaced immediately.