LED tail lights and RFI on the radio

[Ron Dame]

I bought some Holley Retrobright 1157 type LEDs to improve my rear visibility on braking and turning, but whether it's brakes or turn signals, the RFI over my radio is horrible. Interestingly, the stock mechanical flasher works just fine, and trying the electronic LED type made no difference.

JEGS suggested I buy a pack of ferrite chokes off of Amazon ($10 for a bag full) and that would fix it. I popped one on the antenna lead, no improvement. Since I had a bag full, I put a few more on, some with the cable looped around since there were various sizes in the bag. No dice. What the heck, I put them on the tail light power and grounds, nuh uh. Next I called Holley, and they want me to buy some LED load resistors.

So now, I have a LED type flasher and a bunch of chokes, and nothing is any better. Well, OK, but am I just continuing to throw money at the problem, or might this really be the fix?
(Note: I originally posted this on the SDC forums, but other than checking the radio ground, I've gotten no answers)

[Footer]

Ron
I replaced my tail/brake lights with LEDs, even converted the backup lights to 1157s and replaced the front turn signals. No radio interference. I did have to put resistors on each side as the NAPA LED flasher didn’t blink. A fairly simple trial and error test might be to install a different pair of LEDs. Mike

[Ron Dame]

9 hours ago, Footer said:

Ron
I replaced my tail/brake lights with LEDs, even converted the backup lights to 1157s and replaced the front turn signals. No radio interference. I did have to put resistors on each side as the NAPA LED flasher didn’t blink. A fairly simple trial and error test might be to install a different pair of LEDs. Mike

Do you recall what brand lights you used? Interestingly, these Holley bulbs work with the stock flasher!

[Footer]

Sorry, I don’t remember the brand. Think I got them off Amazon a few years ago. Seems like there are lots of choices at Amazon and even auto parts stores. Kind of a trial and error thing. Maybe someone recently replaced their bulbs without radio issues and flasher issues that can weigh in. Mike

[Michael Phillips]

Here's my spin on RF interference. I always look for ground faults, especially on a fiberglass car, meaning if a component has a shaky (corroded) ground circuit it will back feed from the next ground point. In this case I would make sure the antenna is properly grounded, there is a flat metal strap that goes from the antenna base to a frame bolt through the trunk floor. Make sure it is tight and no corrosion. The ground from the taillamp circuit may be carried back to the radio through the negative side of the coaxial cable. Another thing to check is try to isolate the antenna coaxial cable away from the wire bundle that services the taillamps to see if the RF lessens. 

[Ron Dame]

I'll double check the antenna, and the radio ground as well. Thanks!

[ronmanfredi]

I changed all the lights on mine to Auxito 1156 - 1157 off Amazon and there isn't any static.  I also used the United Pacific 90652 Electronic turn signal flasher WITH ground lead for the turn and emergency flaser.  The ground lead is what makes the flasher work with led bulbs without the need to add resistors, etc.  The flasher comes with a reversing adapter in case the fuse box is wired backwards, which my emergency flasher was. (a standard flasher doesn't care what wire is connected to which terminal)..

[Ron Dame]

19 hours ago, ronmanfredi said:

I changed all the lights on mine to Auxito 1156 - 1157 off Amazon and there isn't any static.  I also used the United Pacific 90652 Electronic turn signal flasher WITH ground lead for the turn and emergency flaser.  The ground lead is what makes the flasher work with led bulbs without the need to add resistors, etc.  The flasher comes with a reversing adapter in case the fuse box is wired backwards, which my emergency flasher was. (a standard flasher doesn't care what wire is connected to which terminal)..

Thanks, Ron