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LED resistors for rear turn signals

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Old Sep 29, 2024 | 05:07 AM
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Default LED resistors for rear turn signals

I have a 2007 FXST that Im fitting LED turn signals to, starting at the rear. I dont have room under the seat for some plug and play solution nor am I keen on the price of them.

What wattage and Ohm rating resistors should I be buying?

Thanks
Pete
 
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Old Sep 29, 2024 | 06:45 AM
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Originally Posted by panhead_pete
I have a 2007 FXST that Im fitting LED turn signals to, starting at the rear. I dont have room under the seat for some plug and play solution nor am I keen on the price of them.

What wattage and Ohm rating resistors should I be buying?

Thanks
Pete
They sell small inline Sylvania load equalizer devices at advance auto.
 
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Old Sep 29, 2024 | 06:51 AM
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Sure there plug and play off the self parts out there. There's an advertisement on the right here for them.

However, you can measure the resistance of the original bulb with a ohm meter and go from there.

Plug and play is probably a lot safer if something were to go bad unless your careful where you wire and install a resistor in line.
 
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Old Sep 29, 2024 | 09:14 AM
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Originally Posted by Jackie Paper
Sure there plug and play off the self parts out there. There's an advertisement on the right here for them.

However, you can measure the resistance of the original bulb with a ohm meter and go from there.

Plug and play is probably a lot safer if something were to go bad unless your careful where you wire and install a resistor in line.
Measuring the bulb resistance will NOT work, it will read about 0 ohms when cold and increase very quickly as the bulb heats up and illuminates. Being a 21 watt bulb the resistance is about 6 ohms when hot, resistors sold for this purpose are typically 6 ohms/50 watts.


 
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Old Sep 29, 2024 | 09:24 AM
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I bought a new LED flasher online and tossed the stock module. Cost me all seven bucks. This is radical solution, though, and requires some serious changes in electrical system.
In general, I find it silly the stock flasher won't accept LED bulbs. Once again, H-D is behind times.
 
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Old Sep 29, 2024 | 09:31 AM
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Originally Posted by Von_Zipper
I bought a new LED flasher online and tossed the stock module. Cost me all seven bucks. This is radical solution, though, and requires some serious changes in electrical system.
In general, I find it silly the stock flasher won't accept LED bulbs. Once again, H-D is behind times.

Too cool. I am assuming you are talking about 2007. with a TSM or TSSM. It's also the bankangle kill switch.

They won't run with out that. And its no longer available for the older Harleys

How did you trick the ECM to get around it?

Newer Harleys and for sure those with a BCM work with LED.

But you are right about Harleys reluctance to change. Just the last few years now will read with a common OBII. And even those require and adapter for the plug.

In the case of the early TSM and TSSM read the resistance to alert driver of a malfunction of a signal light out.
 

Last edited by Jackie Paper; Sep 29, 2024 at 09:52 AM.
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Old Sep 29, 2024 | 10:25 AM
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Originally Posted by 08xl1200r
Measuring the bulb resistance will NOT work, it will read about 0 ohms when cold and increase very quickly as the bulb heats up and illuminates. Being a 21 watt bulb the resistance is about 6 ohms when hot, resistors sold for this purpose are typically 6 ohms/50 watts.

Thank.. Good to know. I went LED in my old 2004 simple because I was tired of replacing brake light switches. Second in front and third in rear.

Serve me no use to do it if I put the resistors in since I was trying to reduce load.

I have the all red rear lenses and diode box for making the rear taillight and signal also brake lights. However, didn't put the LED in the rear signal.

The resistance on the LED replacing is zero. My 1157 bulb is 1.2 for running and 3 for the brake element.

Doesn't seem to go to zero on my meter set at 200 ohm.


 

Last edited by Jackie Paper; Sep 29, 2024 at 10:32 AM.
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Old Sep 29, 2024 | 10:32 AM
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My early version of ThunderMax does not play along with TSSM. After installing it the security system was reduced to flashing turn lights while the engine started and ran anyway. Carrying the fob just to pacify the defunct security did not make sense any more. Maybe newer versions of ThunderMax can work with TSSM.
 
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Old Sep 29, 2024 | 03:04 PM
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Originally Posted by Von_Zipper
My early version of ThunderMax does not play along with TSSM. After installing it the security system was reduced to flashing turn lights while the engine started and ran anyway. Carrying the fob just to pacify the defunct security did not make sense any more. Maybe newer versions of ThunderMax can work with TSSM.

So your saying you just pulled the TSSM out from its interface with the ECM and the ThunderMax is a complete ignition and timing for the plugs.

Does the ECM throw any codes that would light up on the console?

In VA, that would not pass a state safety inspection. Doesn't really affect safety but a code light falls in that gray area for what the rules say.
 
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Old Sep 29, 2024 | 03:17 PM
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ThunderMax is the ECM. Full everything. With computer interface which gives the user full control over fuel maps, ignition timing. In addition, it has auto-tune feature. You load in the base configuration for your hardware, cams, compression ratio, pipes. When you start riding it adjusts itself for max power at full throttle and best economy while cruising. I wish I had same kind of unit for my vintage Jaguar.

Edit: Just noticed the last part of your post. It will light up the yellow if anything goes wrong. Then you have to hook up your laptop and see what's up. Once the problem is remedied the yellow will go off.
 

Last edited by Von_Zipper; Sep 29, 2024 at 03:23 PM.
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