HID to LED conversion

The LEDs have been in place for 6 weeks now. They are passively cooled with a finned heatsink. No fan. Heat does not seem to be a problem. The entire inside of the headlight assembly is one large compartment, with various partitions, and the entire assembly is sealed, but air can move by convection throughout the headlight assy. The HID ballast, and the HID bulb are no longer active, and they were the sources of heat inside the headlight assembly. I have not put a temperature probe on the LED heatsink to see hot hot it runs.

Basically, I still like the LEDs EXCEPT FOR the FM radio interference.
I made an attempt at a repair by installing 2 ferrites from old laptop power supplies. I removed the connectors at both ends of the DC-DC converter and soldered in enough wire to get 2 complete wraps of both leads around each ferrite, one on the input, and one on the output. Unfortunately, it made absolutely zero difference in the FM interference. All FM stations are still nothing but static.
Maybe the ferrites are the wrong kind, I don't know. What I do know is that I am out of my knowledge base right now and am looking for help. Here is a picture of the ferrite installation.

 

I've got some copper foil. Maybe I can wrap it with that and solder on a ground wire that I can ground to the car body?

 

Thanks for the comments, everyone.
A couple of updates on the conversion of HID to LED headlights.

(1) There was a concern about the vehicle not passing state inspection because of changing the "type" of headlight in the vehicle. Well, the Prius just past it's annual state inspection at a Toyota dealership. The conversion is totally invisible unless you disassemble the headlights, so maybe I got lucky on that point.

(2) The lights have been installed for over 3 months now, with no glitches in operation at all.

(3) The FM radio interference from the DC-DC power supplies is still unresolved. I think Audio Dave is right and it is being emitted directly from the tiny LED power supplies themselves. Springtime is super busy outside for me, so I will have to "force" a few hours to remove and disassemble the headlights (again !!!!!) to try shielding the power supplies and see if it stops the interference. I certainly hope so!

Lloyd

 

GOOD NEWS UPDATE !

DURABILITY - Excellent so far.
The LED head lights have been performing flawlessly for the 7-1/2 months they've been installed. The car doesn't see a lot of miles, but the headlights are on 100% of the time while the car is being driven.

PERFORMANCE - decent.
Not super bright, but the brightness is safely adequate.

HEAT BUILD-UP - Not an issue.
It's been blazing hot all summer here in Virginia (94F here again today) and no symptoms that I can detect.

ERROR CODES - Nothing showing up on the dash.

LEGALITY - ok, I guess. Definitely maybe.
Went thru state inspection fine at a reputable establishment.

FM RADIO INTERFERENCE - FIXED ! !
Been a while since I posted about this. The problem was that the LED conversion put out some sort of radio interference that made listening to FM impossible when the lights were turned on. AM was fine. It also caused interference in any cars that were directly next to it. Looks like the problem was the cheap DC-DC convertor power supply that came with the lights. First I tried ferrite donuts on the input and output of the convertor. No help. Then I wrapped the convertor and donuts with thin copper foil. No help. Frustrated, I stopped messing with it.
Then davefmy posted today and I figured, what the heck, let's take one last shot at it. I had been meaning to ground the copper foil but had never done it. (Audio Dave, I bet you are laughing.) It was hot outside, but at least i had some shade, and I was hot and sweaty already, so I pulled the headlight out AGAIN, took it into the garage. Un-did the round cover and pulled out the convertor that already had the copper foil wrapped around it, and soldered a 6" long ground wire to the copper foil with a ring lug going to a screw that was already in the internal aluminum framework of the headlight assembly. I put it all back together and it was better, but still some FM interference... from the other headlight... I surmised. Turning the headlights on and off, you could still hear the interference, but less of it.
So, I removed and disconnected the other headlight assy ( 5 minute job, now). Started the car, turned on the FM, turned the headlights on and off, and tried several stations. The interference is gone!! Yea!

The un-fixed headlight is still out and I will put copper foil around it tomorrow, with a soldered-on ground wire, but no ferrite donuts. After I re-install that, I will let you know if the interference is indeed 100% gone.

A funny note to add. I was talking to a friend a while back ( a know it all friend, ha, ha) about the FM interference, and he said, naw, you probably don't need to ground the copper shielding. I honestly knew better, but for some reason I didn't take the extra 10 minutes to solder on a shield ground wire when I put the foil on originally. Trust your instincts, LOL.
Lloyd

 

I put the copper foil RFI shielding on the DC to DC convertor of the other headlight today. The thin copper foil is wrapped around most of the power circuit and a ground wire goes from the copper foil to an existing screw on the solenoid coil that has "22" stamped on it. Here are before and after pics. I soldered the ground lead to the foil and also soldered the laps in the foil here and there just to hold it together a little better. It looks a bit amateurism, and it is, but it seems to work. It all kind of folds up and fits totally inside the headlight, along with all of the original wiring.

The end result is good, but not perfect. On strong FM stations, the interference appears to be gone. On weak FM stations, that already had a little bit of their own interference, the LED conversion added a little bit more interference. The DC to DC convertor probably has a noisy oscillator in its circuitry. A more through shielding job probably would have eliminated all of the interference.

So overall, I am pretty happy with the LED headlight conversion.
Lloyd-ss

 

Aside from having to deal with the FM radio interference problem, I'd say the swap was a 100% success, and I am glad it is encouraging others to give it a try, too.
It seems like the cheap DC to DC voltage convertors/power supplies that have an oscillator in them all put out some sort of noise. I just bought a cheap DC to DC step up convertor (on ebay for about $7) for another project. This was for power into a little audio amp circuit and I bet I tried 15 different ways to eliminate the hum it introduced. I finally stumbled into a pair of current limiting resistors on the out put of the convertor with a 330uF cap across the output. But it only killed the noise if the cap was AFTER the resistors, not before them, and the cap by itself did nothing. I am a total novice at this stuff and some smart electronic person knows why the solution worked.
Lloyd-ss

 

Grease, For starters, you might try just wrapping the little power supply for the fog lamps (assuming they have one) up with some kitchen tin foil and see if that makes any difference. Probably wrap a bare copper wire around it and run it to a ground screw.
For the copper foil, I had some really light gauge copper flashing that had a glued-on paper backing. I scraped off as much of the paper and glue as I could, and it worked, and was plenty solderable.