Connecting Car Lights to your RV for towing might seem complex, but with a few key steps, you can ensure safety and legal compliance on the road. This guide will walk you through the process of using a 2-to-3 wire converter to properly link your car’s lighting system to your RV.
Understanding the Basics
When you tow a car behind an RV, it’s crucial that the car’s brake lights and turn signals mirror those of the RV. This ensures that other drivers are aware of your intentions, preventing accidents. A 2-to-3 wire converter is often necessary because RVs and cars can have different wiring systems, particularly when it comes to brake and turn signal lights being combined on a single wire.
Identifying RV Connector Wires
The first step is to identify the correct wires on your RV that control the brake lights and turn signals. While the exact location of the connectors can vary, the function remains consistent. You’ll need to test each connector to determine its purpose.
A simple test can be performed using a bulb and a ground connection. Connect one end of the bulb to a known ground on the RV. Then, touch the other end of the bulb to each connector in turn. Observe the bulb’s behavior when the RV’s lights are activated:
- Left Turn/Brake Signal: Find the RV connector that lights up the bulb when the RV’s brakes are applied and flashes when the left turn signal is activated. This wire will connect to the “Left/brake” input on your 2-to-3 wire converter.
- Right Turn/Brake Signal: Similarly, locate the connector that illuminates the bulb with the RV’s brakes and flashes with the right turn signal. This will be your “Right/brake” input for the converter.
Locating Car Light Wires
Next, you need to identify the wires on your car that power the rear indicator and brake lights. Access the wiring harness for your car’s tail lights.
- Left Turn Indicator: Locate the wire that specifically activates the left rear turn signal. When 12V power is applied to this wire, only the left rear indicator should light up. Connect this wire to the “left” output of the 2-to-3 wire converter.
- Right Turn Indicator: Find the wire that powers the right rear turn signal. Applying 12V should only illuminate the right rear indicator. Connect this to the “right” output of the converter.
- Brake Lights: Identify the wire(s) that activate the car’s brake lights. Ideally, applying 12V should illuminate all three brake lights (two rear lights and the center high-mount stop light).
Handling Multiple Brake Light Wires
Some cars might have separate wires for each brake light. If you find multiple wires that power the brake lights, you’ll need to use diodes.
- Diodes for Isolation: Install a diode on each brake light wire with the cathode (banded end) connected to the wire itself. Join the anode ends of all the diodes together.
- Connecting to Converter: Connect the joined anode ends of the diodes to the “brake” output of your 2-to-3 wire converter. If your car uses a single wire for all brake lights, you can connect this wire directly to the “brake” output without diodes.
Final Connection and Testing
Once all wires are identified and connected to the 2-to-3 wire converter, ensure that the ground connections are properly established between the RV and the car. This is essential for the converter to function correctly.
After wiring, thoroughly test all car lights to confirm they are working in sync with the RV’s lights. Check brake lights, left and right turn signals, and running lights (if applicable to your setup).
Seeking Further Assistance
If you encounter any difficulties or are unsure about any step, it’s always best to consult with a professional mechanic or RV technician. Providing photos of your wiring setup and diagrams can also be helpful when seeking online assistance or advice.
By following these steps, you can confidently connect your car lights for safe and legal towing behind your RV, ensuring clear communication with other drivers on the road.
