Noise from LED Rigid lights

[itr1275]

Has anybody had a hum or buzz come from LED off road lights? How did you fix it?

A buddy installed a set of Rigid LED lights on his Jeep. OK the first problem is Jeep.

They were installed on the factory driving light circuit an switch.

With the engine off and lights on, driven by the battery only, the lights make a god awful buzzing sound. When you turn on the head lights it gets worse. The sound is still there with the engine on too, but obviously drowned out by the engine a bit.

Imagine a bug zapper sound.

I've only found stuff for house light LEDs seems to be a problem with the current delivery, like a switch or something. The most theory is that it is elector-magnetic emissions causing the noise. Basically excited electrons and stuff.

I know that LEDs are current driven (not voltage driven), so it make sense that loading the battery more might change available current to the lights and change the frequency of the hum/buzz.

As a debug step, I've asked him (still not done) to disconnect one light and see if it gets better. If so then we can say, with some confidence, that it's likely related to current. The next step would be to connect it to a fresh circuit and see if it still happens. This is just theory and debug not yet done.

Thoughts?

 

[rayofsi]

i have a rigid adapt 40 on my raptor.. engine off rigid adapt on and it whines!!

 

[itr1275]

i have a rigid adapt 40 on my raptor.. engine off rigid adapt on and it whines!!

I should tell him it doesn't happen on Toyota's. :wink2:

 

[rayofsi]

I should tell him it doesn't happen on Toyota's. :wink2:

the only rigid lights i currently have on my 4runner are 2 pairs of SR-SAE series fogs. I don't remember it making any noises. have a Baja Designs, Diode Dynamics and Piaa lights with no noises on the 4runner either.

I know the ford has some sort of battery management/ monitoring system. i believe jeep would have it too. Had a Dodge before, lots of fancy electronics

 

[itr1275]

I wanted to follow up on this with some more info. It's not really that much of an issue at this point.

We unplugged one side (only one light operating) and the noise when away. It also doesn't make any noise when the engine is on.

So it's not really an an issue while driving, only if you are parked somewhere and want to land a plane or something.

It was wired into the stock relay and harness. At this point I'm thinking it's a grounding issue (long path) or a current supply issue. There might be components in there causing the current to droop when both are on and the motor is off.

 

[Bugser]

I wanted to follow up on this with some more info. It's not really that much of an issue at this point.

We unplugged one side (only one light operating) and the noise when away. It also doesn't make any noise when the engine is on.

So it's not really an an issue while driving, only if you are parked somewhere and want to land a plane or something.

It was wired into the stock relay and harness. At this point I'm thinking it's a grounding issue (long path) or a current supply issue. There might be components in there causing the current to droop when both are on and the motor is off.

I installed a set of CaliRaised Led fogs that are 3 way....amber, 3400k and 6000k (think those are correct numbers-matters not for this discussion).

I am a dedicated ham op and found that when these are on, The amount of RF leakage is great on 2 meters and is very intense. It’s likely the ballast and needs medal shielding and grounding but I have yet to do this. The leakage doesn’t not affect AM/FM broadcast radio, stresming etc

My 32” led bars have no RF leakage so I’m am guessing it’s the fog ballasts

I’ll post if I figure it out


Sent from my iPhone using Tapatalk

 

[itr1275]

I installed a set of CaliRaised Led fogs that are 3 way....amber, 3400k and 6000k (think those are correct numbers-matters not for this discussion).

I am a dedicated ham op and found that when these are on, The amount of RF leakage is great on 2 meters and is very intense. It’s likely the ballast and needs medal shielding and grounding but I have yet to do this. The leakage doesn’t not affect AM/FM broadcast radio, stresming etc

My 32” led bars have no RF leakage so I’m am guessing it’s the fog ballasts

I’ll post if I figure it out


Sent from my iPhone using Tapatalk

That's a good point there are a few different radios in there and we can see if there is some interference.

 

[david05111]

That's a little worrying. I was planning on outfitting my truck with rigid stuff

 

[itr1275]

That's a little worrying. I was planning on outfitting my truck with rigid stuff

This on a Jeep Wrangler wired through the stock harness. I haven't heard of the same issue with Toyota, wired correctly. But I would check with Rigid and see what they say.

 

[freak4life]

I have rigid’s running through a switch pro and have not noticed a noise, I will turn my radio down and listen closer.

 

[wcjeep]

Do the lights act differently when connected straight to the battery? No relay, no switch. I'm running cheap LED rock lights on my Offroad Jeep and Dodge Tow rig. They emit zero noise. Is the Jeep owner running factory style spark plugs?

 

[itr1275]

Do the lights act differently when connected straight to the battery? No relay, no switch. I'm running cheap LED rock lights on my Offroad Jeep and Dodge Tow rig. They emit zero noise. Is the Jeep owner running factory style spark plugs?

We haven't disassembled the wiring, the installer connected directly to the factory Jeep harness and we didn't want to undo what they did to redo it again. Although, I suspect it would have different behavior. BTW the installer is reputable.

I don't know about the spark plug wires, but the Jeep is well maintained. This only happens when the engine is not running, what is your thought on the wires?

My suspicion is it's a ground problem somewhere, for a few reasons. The Jeep is a recovered flood vehicle. The other part is if you ground to the chassis (which might be a crappy ground being a flood vehicle) you have a long and resistive path to the negative terminal. It gets worse with the head lights on too. The long path, plus loading will result in a voltage drop and possibly susceptible to noise. When we are running one light only, it goes away.

When the engine is running the voltage is higher and able to "power through" (pun intended) the bad ground.

The lights are current driven, and regulated internally with an input of 9-30V; however, a poor ground will be noisy and affect performance.

In the end it's a non-issue, because it doesn't happen when the engine is running. Once we figured this out, we didn't bother to probe the the lights and started drinking beer.

 

[wcjeep]

Newer Chrysler vehicles closely monitor the factory circuits. I woikd be cautious on adding to existing wiring and switches. Chrysler/ FCA not known for long lasting grounds. You could use some jumper cables from the battery ground direct to light ground for testing.

My 1993 off-road Jeep has many cheap led Rock lights that are self ground at their individual mounting location. Only the rear rock lights use the factory backup lights as a trigger. However the trigger signal goes thru a diode, then relay to activate the aftermarket lights.

Your friends Jeep is seeing a voltage drop using the factory switch. It could be the low voltage is the problem.

 

[itr1275]

Newer Chrysler vehicles closely monitor the factory circuits. I woikd be cautious on adding to existing wiring and switches. Chrysler/ FCA not known for long lasting grounds. You could use some jumper cables from the battery ground direct to light ground for testing.

My 1993 off-road Jeep has many cheap led Rock lights that are self ground at their individual mounting location. Only the rear rock lights use the factory backup lights as a trigger. However the trigger signal goes thru a diode, then relay to activate the aftermarket lights.

Your friends Jeep is seeing a voltage drop using the factory switch. It could be the low voltage is the problem.

Thanks, that's exactly what I was thinking. It's not a new Jeep, something like an 06-08 Rubicon. But FCA electronics are still FCA.

 

[wcjeep]

06 was an oddball year Jeep. It had new electronics with old TJ body style. 07 was the new JK body style. 05 and below were not as picky. 06 and up i would definitely recommend not touching the vehicle wiring. Make all add-ons separate from vehicle wiring. The 07 + has twisted pair wiring throughout the vehicle. It's the data ring. Do not touch it. Avoid using bad language around the data ring.

Do not connect the 07+ to strange trailers. The trailer connection wiring is not fused protected. It's a tipm. Google FCA tipm or tipm. Never take it for granted.