Product Description
The Roadmaster 789 is a two-pack of Smart Diodes for towed vehicles with LED taillights. Diodes let the towed vehicle's own taillights show the motorhome's turn, brake and running light signals while preventing current from feeding back into either vehicle's electrical system, which can damage electronic modules.
Many newer vehicles use multiplex (variable-voltage) lighting, where one wire carries several signals at different voltages. The motorhome sends a plain 12-volt signal, so ordinary diodes can leave some taillight functions not working. Smart Diodes take the 12-volt signal and adjust it so the correct lights come on. Two Smart Diodes are needed per vehicle, so this pack covers one towed vehicle. This is the diodes only; you supply the wiring harness and installation supplies, or choose a complete Roadmaster Smart Diode wiring kit instead.
Vehicles with standard incandescent bulbs use a different Smart Diode. Contact us with your vehicle's year, make and model if you're unsure which you need.
Specifications
- Manufacturer: Roadmaster
- Part number: 789
- Type: Smart Diodes (diodes only)
- For: LED taillights / variable-voltage lighting
- Quantity: Set of 2
Features
- Aluminum heat sink helps prevent overheating
- Encased in epoxy for protection from the elements
- Wiring instructions included
Helpful Links
Pro tipWiring and battery tips
- Protect the car’s wiring. Diodes or a separate bulb kit keep the motorhome’s lighting signal from feeding back into the towed vehicle’s electrical system.
- Watch the battery. Some vehicles drain their battery when flat towed; the owner’s manual will say whether you need a charge line or battery disconnect.
Not sure what fits? Send us your vehicle — we’ll confirm before you order.
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