Generally, yes, when upgrading to LED tail lights, you should consider using load resistors, especially on the indicator (turn signal) circuit.
While LED tail lights offer numerous benefits, such as increased brightness, longer lifespan, and lower power consumption, they can sometimes cause issues with a vehicle's electrical system. Here's a breakdown:
-
Why Resistors Might Be Needed:
- Lower Power Consumption: LEDs draw significantly less power than traditional incandescent bulbs. This lower power draw can be interpreted by the vehicle's computer as a bulb being burnt out, leading to "bulb out" warnings on the dashboard.
- Hyper Flashing: The reduced current can also cause the turn signals to flash rapidly, a phenomenon known as "hyper flashing." This occurs because the flasher relay is designed to operate based on the resistance of the standard bulbs.
- Error Codes: Some vehicles' computers may trigger error codes due to the perceived fault in the lighting system.
-
How Resistors Help:
- Simulating Incandescent Bulbs: Load resistors are designed to mimic the power draw of traditional incandescent bulbs. By adding resistance to the circuit, they trick the vehicle's computer into thinking the standard bulbs are still in place.
- Preventing Hyper Flashing: Resistors increase the load on the circuit, allowing the flasher relay to function correctly and preventing hyper flashing.
- Eliminating Error Codes: By replicating the expected power draw, resistors can eliminate the "bulb out" warnings and error codes.
-
Alternatives to Resistors:
- LED-Compatible Flasher Relays: These relays are designed to work with the lower current draw of LEDs, eliminating the need for resistors. They are a plug-and-play solution in many cases.
- ECU (Computer) Programming: Some vehicles allow you to reprogram the ECU to recognize LED lights, bypassing the need for resistors. This typically requires professional assistance.
-
When Resistors Are Not Needed:
- Built-in Resistors: Some LED tail lights come with built-in load resistors, eliminating the need for external resistors. Check the product specifications before installation.
- Vehicles with LED-Ready Systems: Some newer vehicles are designed to work seamlessly with LED lights without any modifications.
-
Choosing the Right Resistors:
- Wattage Rating: Select resistors with an appropriate wattage rating to handle the power load. Consult the LED tail light specifications or a qualified technician.
- Heat Dissipation: Resistors generate heat, so mount them on a metal surface away from flammable materials.
- Proper Installation: Ensure the resistors are correctly wired into the circuit. Poor connections can lead to malfunctions.
In conclusion, while not always strictly required, load resistors are frequently necessary when installing LED tail lights to prevent hyper flashing, error codes, and bulb-out warnings. Consider LED-compatible flasher relays or ECU programming as alternatives.
