Switchback LED Turn Signals

[Old Mike Emerson]

I thought the days of having to wire resisters for LED were gone. I just installed backup LED's and they were plug and play. Am I missing something or are turn signals different?

 

[bflan2001]

I thought the days of having to wire resisters for LED were gone. I just installed backup LED's and they were plug and play. Am I missing something or are turn signals different?

Turn signals need resistors to trick the flasher relay. Other bulbs light brake lights and reverse lights don’t need them. But now with these new bulbs you don’t even need resistors for the turn signal bulbs.

 

[Intuit]

The higher current resistors you add can get rather hot. Curious as to how they're dealing with this. LEDs do not like excessive heat and incorporating a high current resistor with no fan seems like a recipe for early failure.

 

[Old Mike Emerson]

The higher current resistors you add can get rather hot. Curious as to how they're dealing with this. LEDs do not like excessive heat and incorporating a high current resistor with no fan seems like a recipe for early failure.

Thanks for the info, I hate doing thinks wrong. LOL

 

[anticon]

The higher current resistors you add can get rather hot. Curious as to how they're dealing with this. LEDs do not like excessive heat and incorporating a high current resistor with no fan seems like a recipe for early failure.

What exactly do the resistors do? If they just lower the voltage I'm guessing some sort of buck circuit could do that with less heat.

 

[Intuit]

@Old Mike Emerson - If they claim to work without adding resistors I would give them a try. Maybe they figured something out. I added resistors to mine but went through the extra trouble of pulling the pins from the harness in order to make the mod 100% reversible. That takes some time.

@anticon - A blown filament in a bulb opens the circuit and of course an open circuit draws no current. Little or no current made the old flasher relays hyper-flash. The LEDs don't draw enough current, resulting with the hyper-flash. I believe the resistors simulate the additional current of the bulb by converting that energy to heat.

@others - BTW we have no flasher relay. This is all handled internally by the ECU... SO BE CAREFUL...

 

[anticon]

@Old Mike Emerson - If they claim to work without adding resistors I would give them a try. Maybe they figured something out. I added resistors to mine but went through the extra trouble of pulling the pins from the harness in order to make the mod 100% reversible. That takes some time.

@anticon - A blown filament in a bulb opens the circuit and of course an open circuit draws no current. Little or no current made the old flasher relays hyper-flash. The LEDs don't draw enough current, resulting with the hyper-flash. I believe the resistors simulate the additional current of the bulb by converting that energy to heat.

@others - BTW we have no flasher relay. This is all handled internally by the ECU... SO BE CAREFUL...

That makes sense, thank you for explaining.

 

[FocusedSlayer]

I don't have the switch back turn signals but the rear turn signals that I bought have the built-in resistors are bright, and with no hyperflashing . Best way to check them , leave them hanging outside the housing turn your lights on or blinkers and if the don't light up reverse them . Then double check before you put everything back together. At least that's what I did since I didn't have help and it was just me.

 

[bflan2001]

The higher current resistors you add can get rather hot. Curious as to how they're dealing with this. LEDs do not like excessive heat and incorporating a high current resistor with no fan seems like a recipe for early failure.

This is definitely a concern I've had too. I was assuming the bulbs would probably get hot and worst case scenario I damage my housings and get an excuse to upgrade to projectors. I'll be working around the house this weekend so maybe I'll leave my hazards flashing for a while and keep an eye on the temps with an IR gun.

 

[Intuit]

This is definitely a concern I've had too. I was assuming the bulbs would probably get hot and worst case scenario I damage my housings and get an excuse to upgrade to projectors. I'll be working around the house this weekend so maybe I'll leave my hazards flashing for a while and keep an eye on the temps with an IR gun.

Yeah the light bulbs themselves get pretty hot but they're converting a fair amount of energy to light instead of just heat alone. LEDs relatively speaking don't use much wattage but then again I wonder whether their ratings include the high-RPM fans that cool them? Let us know what you find. Sounds interesting.

 

[Buffaloboy]

They were delayed in the mail and I just got them this morning. No hyperflashing, and they are BRIGHT. I tested the radio in the AM band and didn't hear any difference with any of the lights on or off. I don't get very good reception on any AM stations to begin with, so your mileage may vary.

@lovell88 no hyperflashing with LED turn signals all around, including the mirrors.

Here's my current lighting setup:
Front switchback turn signals (3157): https://www.amazon.com/gp/product/B08XBN8T38
Low beam headlights: https://www.amazon.com/dp/B07C1LTQ92
Headlight dust covers (83mm): https://www.amazon.com/dp/B08PTVMQKH
Front side markers, high beams and fog lights are still stock

Mirror turn signals: https://whoosh-motorsports.myshopif...signal-dynamic-led-lights-2014-2019-fiesta-st

Rear turn signals (3157): https://www.amazon.com/dp/B08Z34QY4X
Brake lights: https://www.amazon.com/dp/B06XVT9D1W
Reverse lights: https://www.amazon.com/dp/B074RFY776

Everything works as expected on my otherwise stock 2019 North American Fiesta ST.

Reporting back after running this lighting setup for a few months. Everything works great, and the brighter headlights make a big difference at night. The only downside is that you can hear a bit of buzzing from the fans in the rear turn signal bulbs, pulsing with the turn signals. Having the radio on drowns it out, but it gets a bit annoying if you have the radio off waiting to turn at a long light.