Radio Interference

[72Duster440]

I rewired the entire car using a Painless Wiring harness and ever since, when I turn my turn signals on the radio goes fuzzy. It'll go in and out of being fuzzy as the blinker blinks. I have LED bulbs in my turn signals with an LED specific flasher unit that is grounded separately.

Is there a filter that I can add somewhere to eliminate the interference? It's a Pioneer headunit if that matters.

 

[grjammer]

if it is fuzzy, as in losing the station, it is probably a radiated RF from the flasher causing the radio to drift. Probably move the flasher unit farther from the radio and don't allow the case of the flasher to touch metal if it has a metal body.
If it is fuzzy, as in pops and whistles, shrieks and static, it is probably a grounding issue or a back feed interference issue with the flasher. Without the specifications on the flasher and a real wiring diagram I cant suggest a filter but there are inexpensive power line filters that may work to decouple the noise on the power.
One way to tell is to closely watch the indicator light of the head unit while the turn signals are operating. If it pulses with the turn signals, probably a filter is required. If you can send me a wiring diagram I can look and suggest a cheap fix. part number and manufacturer of the flasher and turn signal led bulbs would help as well.

 

[greg r]

This is one of the reasons I never took the plunge for LED for my old iron, especially ones with working radios. I've installed LED track lighting in the house, and doing research prior to that I've discovered the importance of FCC compliance. While FCC doesn't apply here, again I've discovered LED bulbs "can" cause EMI in radio reception be that AM, FM, handset, or WiFi in the home. My take is it seems to be the bulbs themselves in their intregated switching to fire the diode; usually the cheaper ones have the problem. People have added chokes or ferrite beads in the bulb's voltage supply to varying results or success. I believe the better manufacturers control this, but I don't know what's under the hood except higher price could mean better quality. If the vendor doesn't know, I would have to find one that does; or for that matter what do the guys who build emergency service vehicles use? Some of those are rolling carnivals.

 

[mguner]

I wonder if wrapping the flasher in heavy foil would help....

 

[72Duster440]

Thanks for the replies guys.
It's fuzzy as in static coming through when the turn signal flasher goes on and off. The flasher unit is in the fuse box against the drivers kick panel, it can't go any further away.

The flasher is a LED specific one that has its own ground hookup. The rear bulbs are high quality Philips ones, the front ones are cheap ones. The wire harness is the universal street rod one from Painless.

Flasher - Amazon.com: CEC Industries EF32RL Electronic Turn Signal Flasher Relay, LED Compatible, 2 + Ground Wire Prongs, 12 Volts: Automotive

Rear Bulbs - https://www.amazon.com/gp/product/B00HWS7XGW/?tag=joeychgo-20

Front Bulbs - Amazon.com: JDM ASTAR Super Bright 5730 Chipsets 1157 2057 2357 7528 LED Bulbs with Projector,Amber Yellow: Automotive

Wiring Harness -http://www.painlessperformance.com/webcat/10307
The wiring diagram can be opened from the link.

And the head unit I have is a cheap Pioneer - DEH-150MP - CD Receiver with MP3 Playback and Front AUX-In

 

[67Dart273]

This is one of the reasons I never took the plunge for LED for my old iron, especially ones with working radios. ............I've discovered the importance of FCC compliance. While FCC doesn't apply here, again I've discovered LED bulbs "can" cause EMI in radio reception..............

.....................Somewhat mis-worded? Maybe you meant this:

First the LEDs themselves don't cause RFI, unless involved in transmitter antenna field, which is a whole different thing

Second the FCC IS involved, or "should be." But not in automobile aftermarket LEDs. The thing that is "FCC" so to speak is (home) AC powered LEDs which use a SWITCHING POWER SUPPLY and THAT is what makes all the noise, THAT is what is supposed to be certified (and often is not) None of that applies unless you are talking about the high output HID headlights, which DO use a switching supply.

So far as the OP's problem, just not sure.

Might be defective antenna / coax, or not properly plugged in?

Check radio supply voltage.........Maybe a wiring mistake is "dropping" voltage down during the flasher operation.

Otherwise you can try some bypass caps across the flasher. "The problem" in car wiring is packaging them so they are both robust and yet "short wiring leads" to the flasher.

Sometimes simply relocating the offender helps. Keep the thing "dressed" close to a ground plane.........the metal dash. Try separating the radio power wire from the flasher wiring.

You can also install additional filtering "into" the back of the radio, although it normally should not be necessary.

If you can't do anything else, go to the parts store and get them to look up in the "picture book" (numerical / pictorial listings) a generic radio supression cap. NAPA shows them. Install that as close to the flasher as you can get