When it comes to towing, having a properly functioning trailer wiring system is crucial. If you own a 1999 Ford Expedition, it’s important to understand the wiring diagram in order to make sure your trailer lights and brakes are functioning correctly.
What is a trailer wiring diagram?
A trailer wiring diagram is a schematic representation of the electrical connections between a vehicle and its trailer. It shows how the electrical components are connected and how they function together to provide power to the trailer lights and brakes.
Why is it important to understand the wiring diagram?
Understanding the wiring diagram is important for several reasons:
- Ensuring that the trailer lights and brakes are functioning properly.
- Preventing damage to the vehicle or the trailer due to electrical malfunctions.
- Complying with state and federal towing regulations.
1999 Ford Expedition trailer wiring diagram
The 1999 Ford Expedition trailer wiring diagram consists of several components. These include:
- The trailer connector
- The trailer brake control module
- The trailer tow relay
- The trailer tow fuse
- The battery junction box
Trailer connector
The trailer connector is the point where the vehicle’s wiring harness meets the trailer’s wiring harness. It has several pins that correspond to different functions such as tail lights, brake lights, turn signals, and ground.
Pin-out for the trailer connector
Here’s the pin-out for the 1999 Ford Expedition trailer connector:
| Pin | Function |
|---|---|
| 1 | Ground |
| 2 | Reverse lights |
| 3 | Ground |
| 4 | Tail lights |
| 5 | Left turn signal/brake light |
| 6 | Right turn signal/brake light |
| 7 | Electric brakes |
Trailer brake control module
The trailer brake control module is responsible for sending the appropriate signals to the trailer’s brakes. It ensures that the trailer is braking at the same rate as the vehicle, preventing accidents and damage to the trailer.
Location of the trailer brake control module
The 1999 Ford Expedition trailer brake control module is located under the dashboard on the driver’s side.
Trailer tow relay
The trailer tow relay is responsible for activating the trailer lights and brakes. It ensures that the appropriate signals are sent to the trailer connector and the trailer brake control module.
Location of the trailer tow relay
The 1999 Ford Expedition trailer tow relay is located in the battery junction box under the hood.
Trailer tow fuse
The trailer tow fuse is responsible for protecting the trailer lights and brakes from electrical surges. It is located in the battery junction box.
Fuse rating for the trailer tow fuse
The 1999 Ford Expedition trailer tow fuse has a rating of 20 amps.
Battery junction box
The battery junction box is the central point where the vehicle’s electrical system connects to the battery. It houses several fuses and relays, including the trailer tow relay and the trailer tow fuse.
Location of the battery junction box
The 1999 Ford Expedition battery junction box is located under the hood, near the battery.
FAQ
What kind of trailer can the 1999 Ford Expedition tow?
The 1999 Ford Expedition can tow trailers that weigh up to 8,000 pounds. This includes most types of travel trailers, boat trailers, and small utility trailers.
What happens if the trailer lights or brakes aren’t functioning properly?
If the trailer lights or brakes aren’t functioning properly, it can lead to accidents and damage to the trailer. Additionally, it can result in tickets or fines if you’re not in compliance with state and federal towing regulations.
Do I need a special license to tow a trailer with my 1999 Ford Expedition?
No, you don’t need a special license to tow a trailer with your 1999 Ford Expedition as long as the combined weight of the vehicle and trailer doesn’t exceed 26,000 pounds.
What should I do if I’m having problems with my trailer wiring?
If you’re having problems with your trailer wiring, the first step is to check the wiring diagram to make sure everything is connected properly. If you’re still having issues, it may be helpful to consult a professional mechanic or electrician.
Can I install a trailer brake controller myself?
Yes, you can install a trailer brake controller yourself if you have basic knowledge of electrical systems and the proper tools. However, it’s always recommended to consult a professional if you’re not confident in your abilities.
What do I need to know about towing in adverse weather conditions?
When towing in adverse weather conditions, it’s important to be extra cautious and practice safe driving habits. This includes reducing your speed, maintaining a safe following distance, and avoiding sudden movements or turns.
Conclusion
The 1999 Ford Expedition trailer wiring diagram is an important tool for anyone who plans on towing a trailer with their vehicle. By understanding the diagram, you can ensure that your trailer lights and brakes are functioning properly and that you’re in compliance with state and federal towing regulations. If you have any questions or concerns about your trailer wiring, consult a professional mechanic or electrician for assistance.
