new HID kit interfering with FM radio.

[gu town]

As per title i bought an eBay set of 75w HID and now they are interfering with my FM radio (but not AM) reception only when they are on.

I deliberately bought middle of the range and not the cheapest i could find, to assure some sort of "quality" in the kit from an aussie seller.

I contacted the seller and he has not come across this problem before.

All i've done is made sure all the earth connections are good from there i'm stumped.

The d/s ballast is mounted behind the grill and the p/s is up under the bullbar. They are in rally 4000's if that helps.

[-Scott-]

How long are your earth cables?

[gu town]

only about a foot long. theres two, one main one for the lights going to the relay about 8mm2 and another i presume to earth the coil inside the relay about 2mm2.


I've come across something like this installing big sound systems back when i thought it was cool. we just re-routed the cables and it stopped. re-routing is not really an option as cable length cannot be changed.

I will isolate one ballast, then the other to see if it's a specific ballast then post results.

I assume its something to do with the HV side of the kit and where its touching on the body.....

[-Scott-]

I'm no expert on HID kits, but from an EMC point of view, you really want to get the "noise" to ground as efficiently as possible - and wire is not an efficient HF conductor.

Does the ballast earth through its body, or a wire? Where is the earth point for each ballast? If the passenger side ballast is earthed to the bullbar rather than the body, that would be my no.1 suspect.

[bushy555]

Earth the ballasts (directly to the battery), regardless. If they then stay on all the time, change the positive wiring to turn them on. The ballasts really should be earthed.
Then either get some extension leads between the ballast and the bulb (or make them up yourself), and re-mount the ballasts further away from radio, as well as re-routing the wires to the bulb.
Or, grab some shielded power cable, strip the outer earth shield, and place this shielding over the top of the wires between ballast and bulb, then earth this shielding wire.

See here: http://www.outerlimits4x4.com/viewtopic ... 5#p1600514" onclick="window.open(this.href);return false;

[gu town]

thanks for the replies. i havent done bugger all to fix it yet. will see how i go let ya's know.


bushy... mighty boosh =