Item #PAR-789


Product Description

Use Smart Diodes to wire towed vehicles with multiplex lighting. Smart Diodes can also be used in place of regular diodes.

Diodes are used to prevent the backflow of current to the electrical systems of the towed vehicle and RV. Without them, backfeed can destroy the computer module in either rig. Some newer towed vehicles use a multiplex wiring system, whereby multiple electrical signals may be sent down a single wire (brake and taillights, for example). The signals only vary by voltage. This is why Roadmaster often refers to these vehicles as having variable voltage lighting.

If an ordinary diode is used in these applications, some taillight signals will not work. That's because the motorhome only sends 12 volt signals, but the towed car is expecting different voltages for different taillight functions. Smart Diodes receive the full 12 volts from the motorhome and modify the voltage in order to light up the correct taillight signals on the towed vehicle. 

Because Smart Diodes correctly modulate the voltage to activate only the intended circuit, the result is vehicle lighting that looks and functions as intended. Visit Fitmaster to determine if your vehicle requires Smart Diodes. Even if not required, they can still be used in place of regular diodes. This is beneficial as only 2 Smart Diodes are required per vehicle (traditional diodes require 4 for most vehicles). 

If your vehicle has variable voltage, and uses LED bulbs, choose from the Smart Diode options below. If your variable voltage vehicle has incandescent bulbs you will need Smart Diodes for Incandescent Bulbs instead.

Installers can choose a two-pack of Smart Diodes and provide their own wiring and wiring supplies. Alternatively, use our complete wiring kit that includes two Smart Diodes, a wiring harness to run the electricity from the front of the vehicle to the rear taillights, split loom, ring terminals and other supplies.

• Designed for variable voltage vehicles with LED taillights
• Easy to install - includes wiring instructions
• Aluminum heat sink prevents overheating or failure
• Encased in epoxy for protection from the elements

The 787 is a single Smart Diode for LED bulbs.

The 789 is a two pack of Smart Diodes for LED bulbs.

The 787-12  is a bulk pack of 12 Smart Diodes for LED bulbs.

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